Hmmmm, words from Ralph

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mnc2886

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DOHC is not a good idea. You know that the GTR engine weighs more than an LS7 right? In reality, DOHC is a way for engineers to show off. It would prove no benefit other than maybe sounding better, but I actually like the way a Vette engine sounds and I fell in love with the Viper sound. Although that sound was an acquired taste like beer.

Look a DOHC would require a larger space for the engine, lower reliability believe it or not, and a waste of R&D for SRT.

The two things I think would make a world of difference would be to add a dry sump and DI. The dry sump would add 10-15 HP, reliability, and should let the engine rev a bit higher. The DI would allow for higher compression and more aggressive spark. 11.5:1 is nothing for a DI engine. Not to mention, it would make meeting emissions regulations easier.[/QUOte))

You make interesting points but still wouldn't do it.. DI is very complicated to do and a lot of money for 30-50 hp and you still stuck with the same engine of 1992.
DOHC is not showing off it is proven!!! Look at the gt 500 with the most powerful V8 in the world in a 5.8L with almost 670 hp!!!! GM can't go beyond 638 with a 6.2L!!!! .4 more liter and the numbers are still bellow the dohc.

GTR has a very small engine in a very, very well built package that can hold 800hp or so. GTR is a very heavy car that perform with the Z06 with the vette's lighter weight and better aerodynamic and bigger engine. The gtr has turbos that make the engine weight even heavier overall if you consider them part of the engine. because of being connected to the exhaust manifolds. Z06 engines presented more failures than the GTR engines even though those come with boost.

Look, I think a DOHC has advantages, but the disadvantages are terrible for a Viper platform. Even without the turbos, the GTR engine weighs more. In fact, a BMW 5.0L V10 weighs almost 100 lbs more than an LS7 V8 and makes the same exact power, but less torque. Look at this picture.

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If that doesn't convince you that a engine like this wouldn't be good for a platform where weight and lower center of gravity matter most, then I don't know what will. Again, with all the benefits DI would add, it's much better bang for the buck. The current platform can be amended rather than starting from scratch.
 

KenricGTS

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Yes true that, but DOHC revs harder and can make more pwr. Just breaths better overall. But, I think the Viper can stick with current V10 and turbos or supercharger. I bet 750hp stock would be easy to make with some kind of forced induction. I want the Viper to be the pwr king like back in the day. Can't wait till Paxton or Whipple or someone gets a kit out for gen 5. Better yet SRT, put one on stock!
 

elanderholm

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The Gen iv motor had about the same HP/liter as the ls7. If we use the ratio of the new ls motor in the c7 with DI I would expect a 8.4 liter DI v10 to make about 690. The 5.7 liter DI C7 is supposed to make about 470 so that's the ratio I'm using. To make 750+ I would guess you would need more then just DI. The DI C7 engine includes a compression increase.
 

I Bin Therbefor

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The Gen iv motor had about the same HP/liter as the ls7. If we use the ratio of the new ls motor in the c7 with DI I would expect a 8.4 liter DI v10 to make about 690. The 5.7 liter DI C7 is supposed to make about 470 so that's the ratio I'm using. To make 750+ I would guess you would need more then just DI. The DI C7 engine includes a compression increase.

C7 has a 6.2lt engine advertised at about 450hp. Final numbers not settled as of this date. :headbang:
 

V10lover

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Look, I think a DOHC has advantages, but the disadvantages are terrible for a Viper platform. Even without the turbos, the GTR engine weighs more. In fact, a BMW 5.0L V10 weighs almost 100 lbs more than an LS7 V8 and makes the same exact power, but less torque. Look at this picture.

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If that doesn't convince you that a engine like this wouldn't be good for a platform where weight and lower center of gravity matter most, then I don't know what will. Again, with all the benefits DI would add, it's much better bang for the buck. The current platform can be amended rather than starting from scratch.


Look, There are NO disadvantages for the viper plataform on going with a more efficcient motor only advantages and more power and torque that will make the car win more on the street or race track.

They already made it fit in 1990! in a much narrower car that had the same plataform, bla, bla, bla... IT worked fantastic!! No change in center of gravity, etc... http://www.vettefacts.com/C4/1991.aspx

It is a matter of them wanting to do the right and taking this car to the next level.. the overall it will be more advantages over the old design and is very possible for them to acomplish that.

Another example below of how much more eficcient a DOHC of the same size is compared with a cam in block engine:

1995 mustang GT with a stock 5.0L engine cam in block
5.0L EFI V-8 = 215 hp @ 4200 RPM & 285 lb-ft @ 3400 RPM

VS

2013 Mustang GT with a stock 5.0L engine and DOHC
420hp @ 6500 & 390 lb.-ft. @ 4,250 rpm

Results:

DOHC engine wins with same cubic inch by having 205 more HP(almost double) and 105 more ft-lbs of torque.

YOu compared the BMW V10 and the ls7 but forgot to mention one thing. Their 5.0L engine matched the same HP as the 7Liter GM engine with 2 liters more displacement. Of course the bmw would have less torque as the engine was smaller overall but it again proves how eficient DOHC is. Lets be fair.

The D.I. is not the cure for all the problems and nor is the solution. I describe the GM project on the new C7 as PATHETIC. Their new 5.5L engine with direct injection is making 30hp more than a regular C6 with 430 hp. Again, pathetic, not even the vette fans are approving that 450 hp of the NEW vette. With the use of a modern DOHC engine and the 5.5L they should've been around 525-550 hp MINIMUM.

Oh well, sleepy sleepy, chrysler and chevy.

Let me know when you wake up:dunno:
 

Hirohawa

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We need to be thankful the ZR1 exists... just as Chevy is thankful the Viper exists.

Definitely. The Corvette got infinitely better because of the Viper intro in 1992. It is very good that they both compete with each other it's truly win win. SO happy Gen V gets back into racing too. Should make for even better future cars for both marques.
 

mjf6175

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V10....while I agree with some of your comments I think you are under estimating the benefits of DI. Cadillac sells the CTS with both indirect and direct injection versions of its 3.6 liter V6 engine. The indirect engine produces 270 horsepower while the direct version develops 318 hp. Now that is an 17% increase in power for an engine that is identical except for the DI. So lets be conservative and use 15% for the V10. That would result in 735hp. Use an even more conservative 10% and you are at 705hp. Audi uses DI and has an 12.5:1 compression ratio. Not only does DI allow much higher compression ratios it allows much more aggressive spark timing as well as camshaft events. If Caddy can do it and get these type of results I do not see why SRT cannot do the same. And yes DI is more expensive but I would venture to say that it is less expensive than a DOHC motor and the needed changes. Would I like a DOHC motor? Yes. But I think in the overall picture here looking at what probably is the SRT budget I don't see it in the cards. Plus a DI motor would be able to happen much sooner than an DOHC would take to bring to production.
 

kdaviper

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Most of this discussion is moot, at least for the present. There won't be a power increase until a gen VI engine is developed (if you didn't know, the generations are tied to power output 400,450,500,600,640-I,II,III,IV,V)

BTW, it's no use comparing output per liter between DOHC and CIB engines. More useful would be comparing power output to weight, center of gravity, etc. Also note that in order to make the same power as a CIB engine, DOHC engines need to be running at higher RPMS. Higher RPMs mean more friction, more heat, less efficiency.
 
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chorps

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Look, There are NO disadvantages for the viper plataform on going with a more efficcient motor only advantages and more power and torque that will make the car win more on the street or race track.

They already made it fit in 1990! in a much narrower car that had the same plataform, bla, bla, bla... IT worked fantastic!! No change in center of gravity, etc... http://www.vettefacts.com/C4/1991.aspx

It is a matter of them wanting to do the right and taking this car to the next level.. the overall it will be more advantages over the old design and is very possible for them to acomplish that.

Another example below of how much more eficcient a DOHC of the same size is compared with a cam in block engine:

1995 mustang GT with a stock 5.0L engine cam in block
5.0L EFI V-8 = 215 hp @ 4200 RPM & 285 lb-ft @ 3400 RPM

VS

2013 Mustang GT with a stock 5.0L engine and DOHC
420hp @ 6500 & 390 lb.-ft. @ 4,250 rpm

Results:

DOHC engine wins with same cubic inch by having 205 more HP(almost double) and 105 more ft-lbs of torque.

YOu compared the BMW V10 and the ls7 but forgot to mention one thing. Their 5.0L engine matched the same HP as the 7Liter GM engine with 2 liters more displacement. Of course the bmw would have less torque as the engine was smaller overall but it again proves how eficient DOHC is. Lets be fair.

The D.I. is not the cure for all the problems and nor is the solution. I describe the GM project on the new C7 as PATHETIC. Their new 5.5L engine with direct injection is making 30hp more than a regular C6 with 430 hp. Again, pathetic, not even the vette fans are approving that 450 hp of the NEW vette. With the use of a modern DOHC engine and the 5.5L they should've been around 525-550 hp MINIMUM.

Oh well, sleepy sleepy, chrysler and chevy.

Let me know when you wake up:dunno:

When you say there are no disadvantages, that is out and out a fantasy. Every choice has it's trade-offs. Given the fact that there is no displacement limit for a street car, it makes sense that one should fit the largest engine one can for a performance oriented sports car, but even that is balanced against weight, size, fuel efficiency and cost. *IF* you run up against displacement limits I could see needing to start pushing the breathing efficiency of the engine, but look at the durability cycles of the 'high efficiency smaller displacement engines and compare it to the simplicity of the OHV designs and tell me with a straight face that modern OHVs aren't as good as any OHCs.

It's already been shown time and again that the GM small block engine is one of the most compact engines around, and when compared to other engines, you get more displacement for the same packaging. Obviously the fuel efficiency takes a hit compared to the smaller displacement engines, but fuel efficiency at highway cruising speeds on a sports car isn't going to be priority 1.

I think it's entirely 'fair' to compare the BMW V-10. Who cares that it is smaller displacement, it has to be smaller displacement because it is using an OHC technology, it is a choice the engineers made. GM decided to use OHV for a smaller package and more displacement.

Your argument about a 1995 Mustang engine vs. a 2013 Mustang engine? Seriously cherry picking there...why not just compare a 1995 ZR-1 vs 2006 C6 then? Decades of improvement allow the 'antiquated'* OHV make more power than the DOHC engine.

The new LT1 corvette engine is purported to make nearly as much torque as the LS9 yet have better fuel economy and lower emissions, and more power and torque than the LS3. When are able to swap a GM small block for a Miata engine, you know that is a small engine. The fact that it is 6.2L should give you a clue that OHVs aren't a dead end technology.

*Everyone spouts that OHV technology is old, but OHCs were developed before OHVs were, so technically an OHC design should be considered 'antiquated', for whatever that's worth.
 

Torquemonster

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Direct injection, forged internals, detonation preventing chambers (or pre-chambers) and rear mount twin turbos would get my vote. It takes 0.1 seconds to get the air from the rear to the engine - the delay is immaterial even in racing. Rear mount turbo cars are amongst the fastest on earth, what they lose in a little extra plumbing they make up for in other ways...

- they allow you to keep weight balance
- make more power than a blower per psi boost which would allow for a low boost/high compression car that still makes over 800hp
- does not add parasitic loss to the crank
- allows the same full race spec exhaust headers and system of a blower engine. Combine this with the same attention to the intake and you can have the least backpressure/pressure drop system possible
- does not add unnecessary heat up front.

Blowers are old school.

With over 10:1 and 8.4L you do not need boost under 2500-3000rpm. Compared to a blower, a fully developed rear mount system would provide better mpg, emissions, power, and cooler intake temps (esp with water/**** such as the ERL system) with far lower hood temps and better weight distribution. Set up right you have no throttle lag, and the boost lag is useful not a negative. You cannot hook full boost from a dig on any street tire, so blowers are only better at burn outs, not actual racing.

Realistically boost would be aftermarket, I'd be amazed if SRT was allowed to produce a boosted V10... but it'd certainly be awesome if they did, even if with a blower
 
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V10lover

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V10....while I agree with some of your comments I think you are under estimating the benefits of DI. Cadillac sells the CTS with both indirect and direct injection versions of its 3.6 liter V6 engine. The indirect engine produces 270 horsepower while the direct version develops 318 hp. Now that is an 17% increase in power for an engine that is identical except for the DI. So lets be conservative and use 15% for the V10. That would result in 735hp. Use an even more conservative 10% and you are at 705hp. Audi uses DI and has an 12.5:1 compression ratio. Not only does DI allow much higher compression ratios it allows much more aggressive spark timing as well as camshaft events. If Caddy can do it and get these type of results I do not see why SRT cannot do the same. And yes DI is more expensive but I would venture to say that it is less expensive than a DOHC motor and the needed changes. Would I like a DOHC motor? Yes. But I think in the overall picture here looking at what probably is the SRT budget I don't see it in the cards. Plus a DI motor would be able to happen much sooner than an DOHC would take to bring to production.

D.I. to me is just a band aid to cover the wound. In other words It is not the solution to make the engine as best as it could be naturally aspirated. Just a slap for 15-30 more HP.

Correct me if I am wrong:

C6 = 436 HP

C7 = 450 HP with direct injection

That does not impress me at all. Does that impress you?

I am talking about stock out of the factory, no tuning for agressive timing etc....
 

mnc2886

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D.I. to me is just a band aid to cover the wound. In other words It is not the solution to make the engine as best as it could be naturally aspirated. Just a slap for 15-30 more HP.

Correct me if I am wrong:

C6 = 436 HP

C7 = 450 HP with direct injection

That does not impress me at all. Does that impress you?

I am talking about stock out of the factory, no tuning for agressive timing etc....

Mute point. The compression increase is very minimal. If you move the Viper engine up to 11.5:1, the increase would be very substantial. I also think chevy is holding back just a bit since they already claim the C7 runs door to door with a C6Z. I think that engine has lots of potential, just like our Viper engine.

Also, please don't compare engines 18 years apart. It doesn't prove anything.
 

mjf6175

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You keep using the C7 example. Did you address the numbers with the Caddy engines in my post that you quote? "Just a slap for 15-30 more HP"??? The Caddy's 3.6 liter got a 17% increase. That's 45hp on a 3.6L. Are you saying that a 8.4L is going to only get 15-30HP using DI? When Caddy got 45HP on a 3.6L? The example I used in my first post is an "apples to apples" comparison. I find your comment "stock out of the factory, no tuning for agressive timing etc" inapplicable here since of course both the Caddy engines are stock. Your estimate of 15-30hp is unrealistic, especially when viewed against what was actually gained with a current production engine that has 2 versions to directly compare power outputs and what increase DI gives, stock from GM.

So I ask....Does an increase of 17% impress you?
 

V10lover

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When you say there are no disadvantages, that is out and out a fantasy. Every choice has it's trade-offs. Given the fact that there is no displacement limit for a street car, it makes sense that one should fit the largest engine one can for a performance oriented sports car, but even that is balanced against weight, size, fuel efficiency and cost. *IF* you run up against displacement limits I could see needing to start pushing the breathing efficiency of the engine, but look at the durability cycles of the 'high efficiency smaller displacement engines and compare it to the simplicity of the OHV designs and tell me with a straight face that modern OHVs aren't as good as any OHCs.

It's already been shown time and again that the GM small block engine is one of the most compact engines around, and when compared to other engines, you get more displacement for the same packaging. Obviously the fuel efficiency takes a hit compared to the smaller displacement engines, but fuel efficiency at highway cruising speeds on a sports car isn't going to be priority 1.

I think it's entirely 'fair' to compare the BMW V-10. Who cares that it is smaller displacement, it has to be smaller displacement because it is using an OHC technology, it is a choice the engineers made. GM decided to use OHV for a smaller package and more displacement.

Your argument about a 1995 Mustang engine vs. a 2013 Mustang engine? Seriously cherry picking there...why not just compare a 1995 ZR-1 vs 2006 C6 then? Decades of improvement allow the 'antiquated'* OHV make more power than the DOHC engine.

The new LT1 corvette engine is purported to make nearly as much torque as the LS9 yet have better fuel economy and lower emissions, and more power and torque than the LS3. When are able to swap a GM small block for a Miata engine, you know that is a small engine. The fact that it is 6.2L should give you a clue that OHVs aren't a dead end technology.

*Everyone spouts that OHV technology is old, but OHCs were developed before OHVs were, so technically an OHC design should be considered 'antiquated', for whatever that's worth.

OMG Chorps, How many more times I will have to state that the DOHC is much more efficient than the The old school pushrod motors.

Torque vs RPM/5252 = HORSEPOWER That is why the DOHC engines are unbeatable for power. Your able to spin them way up higher in the rpm band translating in more power and torque. All that in cylinder heads that BREATH a ton. better with 4 valves per cylinder and not only 2 valves like the engine with the cam in block. It is the design that is better my friend!
Yes, Chevrolet engines WERE great.Not anymore, not to me. They are stuck in the mud with this cam in block design and I mentioned before why. I am not explaining it again so ,please, read what I wrote before. The overhead cam design typically allows higher engine speeds because it provides the most direct path between cam and valve.



"Your argument about a 1995 Mustang engine vs. a 2013 Mustang engine? Seriously cherry picking there...why not just compare a 1995 ZR-1 vs 2006 C6 then? Decades of improvement allow the 'antiquated'* OHV make more power than the DOHC engine."

OMG, I made comparos with the same Cubic inch and these two different engine designs and Proved with facts that the DOHC makes more power, torque at mid/high revs than the actual Chevy and Chrysler design.

OK, you wanna compare engines from the same year?

2013 Shelby GT500 - 5.8L V8 DOHC - 662HP @ 6500rpm / 631 lb.-ft. @ 4,000RPM

2012 Camaro ZL1 - 6.2L V8 Cam in block - 580HP and 555 lb. ft

DOHC wins even with smaller cubic inch!


Vette Z06 7.0L V8 Cam in block
505 HP and 470 lb-ft of torque

vs

Lamborghini Aventador 6.5L V12
700 HP and 509 lb-ft of torque

DOHC wins with .5 smaller cubic inch as well.

I could be here for hours giving examples like this but in the meanwhile Will just let you reflect for a little while and realize that cam in block is becaming more than ever a thing of the past. DEad? no they are not dead but they are not a good option to make power N/A anymore when compared to the dohc design. I could care less on stuffing a freaking Gm engine on a POS miata... WHO cares about a crap like that.. I want my viper to have power on high rpms and to be king of the hill again!
 

Torquemonster

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lol re DI being a band aid.

That was funny.

Common rail super high pressure fuel systems enabled diesels to evolve from the dark sooty ages to the state of art engines some of them are today.

DI will do the same for the gas engines.... these are the early days, DI is here to stay and will only get better. Already the C7 stock engine matches or exceeds the torque of the LS7 from idle to 4000rpm from 6.2 vs 7ltr. Audi have run 12:1 successfully on pump gas for years via DI so the power potential is far more than just 15-30. OEM's will typically detune when more power is available to keep gains modest so the cars can evolve and stress be reduced.
 

V10lover

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Mute point. The compression increase is very minimal. If you move the Viper engine up to 11.5:1, the increase would be very substantial. I also think chevy is holding back just a bit since they already claim the C7 runs door to door with a C6Z. I think that engine has lots of potential, just like our Viper engine.

Also, please don't compare engines 18 years apart. It doesn't prove anything.

HUMM, I don't know... Still does not impress me... They have to evolve some how right.. I call that the "lazy way".

C6 Z06 engine is from 2007 and while was great back then we are now in 2013 and they need it to make it better on this next coming c7 vette so they chose that band aid for a little bump in HP. No surprise to me the new c7 running with the Z since they had 6 years to figure that out and still went with the wrong type of engine.
I don't think the C7 has lots of potential at all since those heads will never breath like a DOHC one and by this reason I am OUT and that will never count for me... Our vipers on the other hand because of the huge cubic inch should see a more expressive gain if they adopt the D.I. like you mentioned and your right. Well, at this point still wouldn't do it for me so for that reason I am out too.

"Also, please don't compare engines 18 years apart. It doesn't prove anything."

Your wrong on this one. It proves a lot. It proves technology and 18 bright years of progress on the right direction of the DOHC technology of ford and gains of almost double the horsepower with the same cubic inch of a cam in block design engine. I remember that they even offered an ultra modified 5 liter with nasty cam/heads and of road exhaust that could barely reach 350 hp for the cam in block engine and of course would never pass emissions anyways.. haha just funny thing...

I love my viper but have to admit, we are way back there behind the pack running with chevy when it comes to making engines in todays world. Just my 0.2 cents.
 

sonofadragracer

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Blowers are old school.

You cannot hook full boost from a STANDING START on any street tire, so blowers are only better at burn outs, not actual racing....for the street.

Realistically boost would be aftermarket, I'd be amazed if SRT was allowed to produce a boosted V10... but it'd certainly be awesome if they did, even if with a blower

Fixed it some TQ!!!! :D

TQ!!!!!!! You know I'm all about the WASHING MACHINE!!!!
There's a reason why we stick with the Blower in TF?..IT WORKS! We tried jerking the Blower and running Nitrous on an injected setup on Nitro...couldn't get the damn thing to work. My Dad's buddy Chase Knight tried twin turbos on the fueler for 3 DAMN YEARS!!!! Couldn't get it to work.

I know I'm talking about way different things, but for what I know most about there's no other. I don't like Turbos.
Just don't...... always to many variables...oiling to turbo issues, plumbing, etc. etc.

Not saying they're not bada$$ for the street and some forms of Racing.. But I'm jus a SC kinda guy.
Hope you're good Buddy, sent you a PM.
 
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V10lover

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lol re DI being a band aid.

That was funny.

Common rail super high pressure fuel systems enabled diesels to evolve from the dark sooty ages to the state of art engines some of them are today.

DI will do the same for the gas engines.... these are the early days, DI is here to stay and will only get better. Already the C7 stock engine matches or exceeds the torque of the LS7 from idle to 4000rpm from 6.2 vs 7ltr. Audi have run 12:1 successfully on pump gas for years via DI so the power potential is far more than just 15-30. OEM's will typically detune when more power is available to keep gains modest so the cars can evolve and stress be reduced.

It is a band aid so they make a little more power with the old design engine and everybody is happy again. NOT ME and I am not buying any of these cars with this band aids installed to it.
It will mask the deficiencies of those motors making 10% more power but those issues will still be there cause those engines just have a hard time to spin high sustaining torque.

They should do it right and once and for all and not be delaying changing the engine design. Start with the right pair of cylinder heads and from there ad the D.I.

I have nothing against D.I. but it is truly a band-aid for these cam in block engines.... Engine is still limited by the deficiencies of the cylinder heads to make SERIOUS horsepower sustaining higher RPM.

Buy your modern cam in block engines with the D.I. and think your cars will become king of the hill again.. You will be doing nothing but fooling yourselfs..
 

doctorbob

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I am the first to admit that I am not a gearhead.........in my specialty sticking your fingers in moving engine parts is not a good thing. I will let SRT develop the engine. I just drive them. As Paul Hawker posted on my thread in the VCA owners' section and at the Southern Cal event:

"We got to have an open conversation with Dick Winkles. This is the same guy that has been involved with the Viper engine program since the very beginning. He took the road trip with Ralph. He mentioned the significant improvements made to this edition of the motor. He elaborated how this engine breathes better than any that came before, how the internals have been beefed up to add a level of robustness necessory as aftermarket tuners bump it up even more. He addressed how they have some plans for the future development of this motor that can give it long life with additional refinements and development. Also indicated that it will take more time and money to get there. He was very proud of what they have accomplished, and that with this engine they have a solid foundation for future enhancements."
 

ACRucrazy

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:drive:..........
"We got to have an open conversation with Dick Winkles. This is the same guy that has been involved with the Viper engine program since the very beginning. He took the road trip with Ralph. He mentioned the significant improvements made to this edition of the motor. He elaborated how this engine breathes better than any that came before, how the internals have been beefed up to add a level of robustness necessory as aftermarket tuners bump it up even more. He addressed how they have some plans for the future development of this motor that can give it long life with additional refinements and development. Also indicated that it will take more time and money to get there. He was very proud of what they have accomplished, and that with this engine they have a solid foundation for future enhancements."
 

chorps

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OMG Chorps, How many more times I will have to state that the DOHC is much more efficient than the The old school pushrod motors.

Torque vs RPM/5252 = HORSEPOWER That is why the DOHC engines are unbeatable for power. Your able to spin them way up higher in the rpm band translating in more power and torque. All that in cylinder heads that BREATH a ton. better with 4 valves per cylinder and not only 2 valves like the engine with the cam in block. It is the design that is better my friend!
Yes, Chevrolet engines WERE great.Not anymore, not to me. They are stuck in the mud with this cam in block design and I mentioned before why. I am not explaining it again so ,please, read what I wrote before. The overhead cam design typically allows higher engine speeds because it provides the most direct path between cam and valve.

"Your argument about a 1995 Mustang engine vs. a 2013 Mustang engine? Seriously cherry picking there...why not just compare a 1995 ZR-1 vs 2006 C6 then? Decades of improvement allow the 'antiquated'* OHV make more power than the DOHC engine."

OMG, I made comparos with the same Cubic inch and these two different engine designs and Proved with facts that the DOHC makes more power, torque at mid/high revs than the actual Chevy and Chrysler design.

OK, you wanna compare engines from the same year?

2013 Shelby GT500 - 5.8L V8 DOHC - 662HP @ 6500rpm / 631 lb.-ft. @ 4,000RPM

2012 Camaro ZL1 - 6.2L V8 Cam in block - 580HP and 555 lb. ft

DOHC wins even with smaller cubic inch!


Vette Z06 7.0L V8 Cam in block
505 HP and 470 lb-ft of torque

vs

Lamborghini Aventador 6.5L V12
700 HP and 509 lb-ft of torque

DOHC wins with .5 smaller cubic inch as well.

I could be here for hours giving examples like this but in the meanwhile Will just let you reflect for a little while and realize that cam in block is becaming more than ever a thing of the past. DEad? no they are not dead but they are not a good option to make power N/A anymore when compared to the dohc design. I could care less on stuffing a freaking Gm engine on a POS miata... WHO cares about a crap like that.. I want my viper to have power on high rpms and to be king of the hill again!

Again, you have a strange obsession with displacement restrictions and comparisons...who really cares? Stuffing a big engine into the engine bay is a great strategy, and whilst DOHC allows for better breathing, the trade off is a taller package and higher center of gravity...other vehicles have different packaging constraints so they may be able to fit a DOHC design, but usually it is a smaller displacement as a trade off. I don't see too many other cars making similar power to the Viper that aren't forced induction or super expensive. You have this idea that top end breathing is *everything,* but there are many other factors to look at...higher piston speeds mean more frictional drag and requires better metallurgy which means a higher cost to produce and maintain those engines, and a shorter duty cycle.

I'm pretty sure the ZL1's LSA was spec'd to produce less power than the ZR1 (1.9L supercharger vs a 2.3L supercharger), while the GT500 has no big brother to contend with. If you compare the LS9, the Ford isn't as far off as you'd expect for a 14psi boost vs. the LS9 10.5 pounds of boost, or the LSA's 9 pounds. I'm pretty sure if you upped the boost on the LS9 or LSA they would be very competitive with the GT500. The Ford engine is awesome, but I wouldn't chalk up the advantage to just DOHC vs OHV. I'm not sure what the dimensions of the Ford engine are, but I'm pretty sure it's bigger and heavier than the LS9 or LSA.
You want to keep up with this 1995 Mustang vs 2013 Mustang comparison? Really? The *only* reason that the 2013 Mustang makes more power than a 1995 Mustang is because it has DOHC? Really? :lmao:

Bottom line is, every solution has it's advantages and disadvantages, and I don't think that going DOHC is going to magically make the Viper a significantly better vehicle than an OHV one when you compare the cost to build and maintain it over the long run. I'm not even sure why you're making a claim that the Viper *needs* to radically switch engine configurations when the Viper is easily in the top rung (Gen IV ACR, Gen V) and duking it out with another OHV contender for the top dog (ZR1).

Outside of really exotic machinery ($$$$), both the Viper and Corvette eat up the competition...only ultra exotic low production, super lightened cars are considered to be faster. So yeah, I'd expect a 6.5L V12 Aventador to make more power than a 7L V8, simply because one costs more than 4x the price of the other...again though, having been introduced in 2007, the Z06 puts up a really good fight against the Aventador which debuted in 2011.

Funny that the Z06 with Z07 package laps the green hell faster than the Aventador, so maybe the packaging of a the 6.5L V12 DOHC makes too many sacrifices vs. a 7L V8 OHV. 7:19 vs 7:25. Of course the Viper ACR is faster than them both at 7:12 but every Viper owner knows that. :D

I understand you want the Viper to kick ass and be the top contender bar none - I think every VCA member does, but if you wanted ABSOLUTE performance from Chrysler, you wouldn't have a Viper anymore. You'd have this car instead:

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No thanks. I couldn't afford it anyway. I know that there have been discussions at the mothership about making the Viper mid engine, because it is the best place to put an engine. I'm glad they haven't gotten any traction with that. Still don't think OHC is a good plan either.
 

v10enomous

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I love the GenV and adding a blower would be great for a couple of years out but the at the end of the day the GenV is pretty much a design from 1989.:dunno: I like the idea of a fresh platform at some point. It has to happen for the Viper to have any chance going forward. I like the ME412 and even have the scale model in my office. I would think with Ferrari they could come up with something that would be affordable. Hell... Porsche and Lotus can build affordable mid-engine designs. Lower, wider, lighter is the future imo. It doesn't even have to be mid-engine but let's face it the new base corvette C7 is a 3,000lb V8 aluminum frame car with what some believe is 470hp+.

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SnakeBitten

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Look, I think a DOHC has advantages, but the disadvantages are terrible for a Viper platform. Even without the turbos, the GTR engine weighs more. In fact, a BMW 5.0L V10 weighs almost 100 lbs more than an LS7 V8 and makes the same exact power, but less torque. Look at this picture.

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If that doesn't convince you that a engine like this wouldn't be good for a platform where weight and lower center of gravity matter most, then I don't know what will. Again, with all the benefits DI would add, it's much better bang for the buck. The current platform can be amended rather than starting from scratch.

Wow a picture is worth a thousand words. A little off topic but I still am amazed that those V8's fit into RX-7's without messing with the cars stock balance. Ive heard that the V8 engine and its ancillary pieces are lighter than the 1.3 l Rotary and its ancillary pieces. With the V8 swap they don't just get more power but more reliability and much better fuel economy. Not bad for supposed yestertech. If it broke........
 
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ViperSmith

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I love the GenV and adding a blower would be great for a couple of years out but the at the end of the day the GenV is pretty much a design from 1989.:dunno: I like the idea of a fresh platform at some point. It has to happen for the Viper to have any chance going forward. I like the ME412 and even have the scale model in my office. I would think with Ferrari they could come up with something that would be affordable. Hell... Porsche and Lotus can build affordable mid-engine designs. Lower, wider, lighter is the future imo. It doesn't even have to be mid-engine but let's face it the new base corvette C7 is a 3,000lb V8 aluminum frame car with what some believe is 470hp+.

You must be registered for see images attach

I think saying a Viper "always has to be a clown shoe" will hold it back in the long run, so I agree.
 

V10lover

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Again, you have a strange obsession with displacement restrictions and comparisons...who really cares? Stuffing a big engine into the engine bay is a great strategy, and whilst DOHC allows for better breathing, the trade off is a taller package and higher center of gravity...other vehicles have different packaging constraints so they may be able to fit a DOHC design, but usually it is a smaller displacement as a trade off. I don't see too many other cars making similar power to the Viper that aren't forced induction or super expensive. You have this idea that top end breathing is *everything,* but there are many other factors to look at...higher piston speeds mean more frictional drag and requires better metallurgy which means a higher cost to produce and maintain those engines, and a shorter duty cycle.

I'm pretty sure the ZL1's LSA was spec'd to produce less power than the ZR1 (1.9L supercharger vs a 2.3L supercharger), while the GT500 has no big brother to contend with. If you compare the LS9, the Ford isn't as far off as you'd expect for a 14psi boost vs. the LS9 10.5 pounds of boost, or the LSA's 9 pounds. I'm pretty sure if you upped the boost on the LS9 or LSA they would be very competitive with the GT500. The Ford engine is awesome, but I wouldn't chalk up the advantage to just DOHC vs OHV. I'm not sure what the dimensions of the Ford engine are, but I'm pretty sure it's bigger and heavier than the LS9 or LSA.
You want to keep up with this 1995 Mustang vs 2013 Mustang comparison? Really? The *only* reason that the 2013 Mustang makes more power than a 1995 Mustang is because it has DOHC? Really? :lmao:

Bottom line is, every solution has it's advantages and disadvantages, and I don't think that going DOHC is going to magically make the Viper a significantly better vehicle than an OHV one when you compare the cost to build and maintain it over the long run. I'm not even sure why you're making a claim that the Viper *needs* to radically switch engine configurations when the Viper is easily in the top rung (Gen IV ACR, Gen V) and duking it out with another OHV contender for the top dog (ZR1).

Outside of really exotic machinery ($$$$), both the Viper and Corvette eat up the competition...only ultra exotic low production, super lightened cars are considered to be faster. So yeah, I'd expect a 6.5L V12 Aventador to make more power than a 7L V8, simply because one costs more than 4x the price of the other...again though, having been introduced in 2007, the Z06 puts up a really good fight against the Aventador which debuted in 2011.

Funny that the Z06 with Z07 package laps the green hell faster than the Aventador, so maybe the packaging of a the 6.5L V12 DOHC makes too many sacrifices vs. a 7L V8 OHV. 7:19 vs 7:25. Of course the Viper ACR is faster than them both at 7:12 but every Viper owner knows that. :D

I understand you want the Viper to kick ass and be the top contender bar none - I think every VCA member does, but if you wanted ABSOLUTE performance from Chrysler, you wouldn't have a Viper anymore. You'd have this car instead:

You must be registered for see images attach


No thanks. I couldn't afford it anyway. I know that there have been discussions at the mothership about making the Viper mid engine, because it is the best place to put an engine. I'm glad they haven't gotten any traction with that. Still don't think OHC is a good plan either.

OK, MR old school.
 

V10lover

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I love the GenV and adding a blower would be great for a couple of years out but the at the end of the day the GenV is pretty much a design from 1989.:dunno: I like the idea of a fresh platform at some point. It has to happen for the Viper to have any chance going forward. I like the ME412 and even have the scale model in my office. I would think with Ferrari they could come up with something that would be affordable. Hell... Porsche and Lotus can build affordable mid-engine designs. Lower, wider, lighter is the future imo. It doesn't even have to be mid-engine but let's face it the new base corvette C7 is a 3,000lb V8 aluminum frame car with what some believe is 470hp+.

You must be registered for see images attach

Exactly!

That's what I am trying to talk to some guys here but they don't seem to understand what I was saying. They either get mad or are really scared of change?

Our vipers did amazing over the years but like any project everything reaches a point where is SATURATED and you just can't squeeze anything more out of it with the tighter and tighter restrictions.

Everything has a birth / life / death.

The viper died in 2010 and since it is resurrection the old motor should never been chosen again to be part of this gorgeus and sophisticated gen V car.
 

BigDawg

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The viper died in 2010 and since it is resurrection the old motor should never been chosen again to be part of this gorgeus and sophisticated gen V car.

Don't forget the aftermarket. The massive and simple Viper engine is VERY mod friendly. You will alienate a huge group of Viper buyers by making the engine less mod friendly. There is no replacement for displacement. You can beat the hell out of a Viper motor because it's a beast. Keep it a beast. If you don't like it, there are plenty of other options.
 

V10lover

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Wow a picture is worth a thousand words. A little off topic but I still am amazed that those V8's fit into RX-7's without messing with the cars stock balance. Ive heard that the V8 engine and its ancillary pieces are lighter than the 1.3 l Rotary and its ancillary pieces. With the V8 swap they don't just get more power but more reliability and much better fuel economy. Not bad for supposed yestertech. If it broke........

Which one would you pick if I tell you that the bigger engine on the LEFT makes 205 more HP than the one on the right?

Your choice.

Screw miatas, Put any of those engines in a REAL CAR!
 

V10lover

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Don't forget the aftermarket. The massive and simple Viper engine is VERY mod friendly. You will alienate a huge group of Viper buyers by making the engine less mod friendly. There is no replacement for displacement. You can beat the hell out of a Viper motor because it's a beast. Keep it a beast. If you don't like it, there are plenty of other options.

Aftermarket? What aftermarket? They didn't even unlock the ECU on GEN 4s and 6.4L challengers yet..

I understand the engine is very stout, but like any N/A with a cam in block /2vl/ cyl, it got saturated. In this case is at 640HP because they won't be able to add a nasty cam or more compression out of the factory and passing emissions with that. I gotta pass emissions. People in California gotta pass emissions and so do people in other states. The DOHC opens an interesting teritory never explored by the viper before with way more potential for power than the cam in block engine while still passing emissions and retaining quite large cubic inch on the V10 too.

The DOHC engine is very mod friendly and as we know is a very old design which is just more efficient than the actual viper/vette engine.
The new 5.0L mustang with the DOHC engine has more aftermarket parts and choices than ever before. So does the GT-500. Everybody is happy; middle age guys, old, young, women.. I personally bought a new 2013 GT and couldn't be happier. I spin my DOHC engine to almost 8000rpm on my way to work everyday and to tell you the true I am having more fun than I ever had driving my viper. I'm also forging the motor this summer to install twin turbos for 1200HP. Great times!:)

The VIPER and VETTE world CANNOT depend on the old crowd because of their traditionalism and fear of evolving to better motors. It is just ridiculous.
The cam in block Has to go in my opinion and there is something more important which is planting a seed for the future and the next generations of buyers. If it were for that old crowd we would all be driving 32 hot rods. Those times are gone and they were good while they last.

All I defend is the car having modern cyl. heads to go with a larger C.I. engine. Would hate to see the viper with little motor. even with a 7.8L V10 we would be making a lot more power than the actual saturated 8.4L
 
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