OK. One of U out there must be working on boost. Give it up.

Nine Ball

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We (customers)have been hearing excuses for years for the Gen. 4s and now same spin for the Gen.5.Please,the new C7 Corvette is just out and they are already at the tuner shops.

When it comes to supporting the aftermarket, GM is far ahead of Chrysler and Ford. Chrysler is a distant 3rd place, unfortunately. Through my GM past, I have a lot of contacts that are involved in their performance parts and vehicles group. These guys are true gearheads, and support the tuner shops and the aftermarket industry. Example, the C7 Corvette. GM performance made LT1 (the newest engine) head castings available to some of the more popular LSX shops and big-name manufacturers, so that they could experiment with them - months before the cars were to become available. They also sent LT1 crate engines to some of those shops, so that they could begin developing bolt-on parts, do engine dynos, and explore the engines. What other brand does that? So, now that the C7 Corvette has been on the dealer lots for a week now, the aftermarket is already ramping up for it. Count on a LOT of parts developed for this car to be unveiled at SEMA in November. Likely far more parts than the Gen V Viper will have available. GM has also hosted some multi-day track rentals to showcase and teach the LSX tuners about the C7. Not magazine guys, actual guys that will build and modify these cars. Their Facebook updates make me envious.

I figured SRT might offer something similar for the Gen V Viper, but I was wrong. I inquired about purchasing a raw head casting for one of my contacts that produces ported LSX cylinder heads, as they want to develop Viper parts too. The SRT contact got offended that I asked about it, and told me there was nothing to gain in the head, and that I shouldn't question Winkles. Wait...what? I just wanted to help get the aftermarket involved, I didn't expect a reprimand.

Like I said, BIG difference.
 

Malu59RT

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So what would you replace a stock GenIV piston with? ACR-X pistons or Gen V pistons? Or another brand? How much power would you lose by going forged piston? Is this a track only issue?

You wouldn't lose power by using a forged piston, power would only be lost if you lowered the compression. Personally, if I spent the labor to go into the short block, I would use aftermarket rods and pistons, and sleep better knowing I had strong pistons and rods in there.
 

ACRucrazy

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I inquired about purchasing a raw head casting for one of my contacts that produces ported LSX cylinder heads, as they want to develop Viper parts too. The SRT contact got offended that I asked about it, and told me there was nothing to gain in the head, and that I shouldn't question Winkles. Wait...what?

Yet all these ported head Gen IVs are putting down 625-650 to the tire and the stock Gen IVs are having a hard time breaking 550..
I swear... sometimes I wonder.. :crazy2:
 

C-Note

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You wouldn't lose power by using a forged piston, power would only be lost if you lowered the compression. Personally, if I spent the labor to go into the short block, I would use aftermarket rods and pistons, and sleep better knowing I had strong pistons and rods in there.

Not quite true... Hypereutectic pistons do not absorb as much energy as forged pistons in other words they reflect the explosion better. You will lose a little power switching to forged pistons at the exact same compression, not to mention the weight the piston will be picking up...

Switching to a hypereutectic piston is how they kept the power up when they dumbed down the cam in the so called cream puff engines and is the main reason they got away from forged pistons years ago.
 
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Bobpantax

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It is a little off the intended topic of my OP but perhaps interesting to some. My understanding of what part of the problem is with Chrysler produced aftermarket equipment is that the engineering philosophy of Mercedes is still in place. What does this mean? It appears to mean that the Mercedes engineering philosophy is airplane production and durability based. A higher standard that is not used by Ford or GM. This may explain why the SRT answer to the ZL1 and the GT500 is taking so long to produce and why, in addition to the calibration code ownership issue mentioned by Mark J and the tight reigns Chrysler legal maintains regarding warranty fraud exposure that the Gen IV code has not been unlocked and, apparently, the Gen V code will not be unlocked either. Someone somewhere within Chrysler should revisit the issue and see if the business case for changing how they view these variables has changed enough to loosen things up a bit. The status quo acts to tie the hands of SRT and Mopar and may be costing or may cost Chrysler far more sales than originally thought.
It is very frustrating.....if you do not want to modify a car, buy a Chrysler product. If mods are in your future, buy a Ford, GM, Italian, German, Japanese or British car. The Ford GT of the future will be the 2006 Gen 3 Coupe. Pretty much the same chassis as the Gen 4 and Gen 5 but with huge mod potential.

I've given up hope after waiting 5 years and have started buying other brands that can be modified. Mark my words, this will effect Chrysler's sales in the next 24 months and Sergio will be wondering where the cash cow that was helping Fiat went. Forget Vipers, but when Jeeps, Rams, Darts, Challengers and Chargers can't be easily modified.....it's just way too easy to walk across the street and pick up a Ford or GM product. And once you switch brands, it's very easy to stay with that brand. Imagine what the Chrysler bottom line would look like with just a sales drop of 5% off the Ram and Jeep line....Yikes!!

Cheers,
George
 

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So what would you replace a stock GenIV piston with? ACR-X pistons or Gen V pistons? Or another brand? How much power would you lose by going forged piston? Is this a track only issue?

From what I can tell before getting one in hand, the Gen-5 piston is likely the exact same piston as the ACRX, or at least nearly completely based on it. That was a tried and true available piston from their primary piston supplier.

The difference going to a forged piston is minimal. There are slightly higher conductivity losses, and a little more blow-by... but we are talking peanuts overall.

It is primarily a track issue, but I have seen it on a few street engines.
 
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Bobpantax

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Dick Winkles already publicly stated that the Gen V piston is based on what they learned in, and while, developing the ACRX piston.
From what I can tell before getting one in hand, the Gen-5 piston is likely the exact same piston as the ACRX, or at least nearly completely based on it. That was a tried and true available piston from their primary piston supplier.

The difference going to a forged piston is minimal. There are slightly higher conductivity losses, and a little more blow-by... but we are talking peanuts overall.

It is primarily a track issue, but I have seen it on a few street engines.
 

Viper Specialty

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Yet all these ported head Gen IVs are putting down 625-650 to the tire and the stock Gen IVs are having a hard time breaking 550..
I swear... sometimes I wonder.. :crazy2:


That being said, I have STOCK head Gen-4 conversions making those same kind of power numbers on very mild camshafts. Its not "just" the head porting. Those ported head cars surely have FAAAAR more modifications than just the heads. I am not going to argue that higher flowing heads wont produce more power, but if you cannot feed them properly, its a moot point. There was more to gain UP FRONT in the manifold than the heads, and I think that was what he [Dick Winkles] was getting it. A chain is only as strong as its weakest link, and I think in the case of the Gen-4, while very evenly matched overall, the manifold's number came up first.

Compare two identically modded cars with and without the heads, with the ability to tune- that would be a fair comparison. With a static tune, you can fall into a trap of having a maximized vs far off tune due to modifications, which will skew what the real results are.
 
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ACRucrazy

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That being said, I have STOCK head Gen-4 conversions making those same kind of power numbers on very mild camshafts. Its not "just" the head porting. Those ported head cars surely have FAAAAR more modifications than just the heads.

I agree they have more mods than just ported heads, that's not what I was trying to imply. But I don't know if I would call a ported lower intake, standard headers/exhaust and a bolt on Mopar PCM really FAAAAR more modifications. 600 WHP in a Gen IV should be pretty easy. I/H/E & PCM and you should be there. (It's not like there are tons of off the shelf bolt on engine parts for these cars. The Gen IV mod list is pretty cookie cutter that yields very similar results across the board IMO)

The ported heads &/or cam is the icing on the cake, 25-50whp worth of icing I suppose. All my point was that there is something to be gained in the heads, I know you understood that. Now I am just thinking out loud. I totally get the weakest link bit too. But for SRT to supposedly throw up a wall with a reply like that when Tony was trying to get an aftermarket company involved is just silly.
 
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Bobpantax

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No. Only a twin screw type blower. A centrifugal type will fit. The car could be Paxtonized if the controller could be recalibrated.
 

Tom Welch

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I'm currently tinkering with a Nitrous setup for my Gen V. Will let you guys know how it goes. The good thing about a balanced Nitrous Kit
is that you eliminate any need for ECU tuning. My only concern on these new "smart cars" is getting the nitrous through the maze of sniffers
and OEM gadgets that could hinder its performance or reduce timing and torque to offset the instantaneous increases that Nitrous provides.

The system I'm putting together will use manual interface, meaning basic "old school" techniques that will ensure safe activation and operation of the
system.

I hope to have it installed and on the dyno soon. At this point, other then Nitrous, it appears that typical bolt ons such as exhaust systems and
air intake modifications have shown little to no gains in performance compared to earlier year Vipers....especially for the amount of dollars spent. A
20HP gain for a complete exhaust system that comes with a FREE set of CEL codes..LOL...just doesn't seem like a bargain to me.

I wish I could take the ECU off of my 97' and install it on this car.....now there's an idea for you techies! The engine specs of the Gen V are superior
to any Gen I, III, and IV Vipers, with only the 96 and 97 Gen II's having similar forged internals that can take the increased cylinder temperature and pressure
induced by Nitrous or Forced Air from Supercharger and Turbocharger applications.
 

Viper Specialty

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The engine specs of the Gen V are superior
to any Gen I, III, and IV Vipers, with only the 96 and 97 Gen II's having similar forged internals that can take the increased cylinder temperature and pressure
induced by Nitrous or Forced Air from Supercharger and Turbocharger applications

Superior, Yes. However, when you factor in the hardware used to hold Gen-4 and 5 engines together, they are not necessarily the most conducive for Nitrous. I see head gasket failures in the future of any unmodified 4 & 5 engines which are used for any decent amount of power production, but especially NOS given the cylinder pressure/torque.
 
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