GEN II modified to compete with GEN IV ACR

1. 
   Corded Tires
   Less HP
   Stock ride height
   Something in my eye
   Fat passenger
   I had to ***
   I was not staying at a Holiday Inn Express

shooter_t1 said:

Couldn't have been that good, Mike in his 97 gts with no aero was all over you. Maybe you should stick to Ducati's.

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Smokin' 2 said:

NI-KA said:

There are alot of things that can be done but is there any hope that a modded GEN II can keep up with the GEN IV ACR?
QUOTE]

I've been where you're at. Got your PM. There is a lot of great advice already in this thread from people I would assume are more experienced than myself. I got my GTS and myself to the point where I was respectably fast and then promptly bought an ACR after getting to drive one.

A lot of the answer depends on the type of track and habits of the driver.
It goes without saying that you should invest in the slowest thing in the car if you haven't already: the software between the seat and the steering wheel. I ran with a few ACR's at the track where the driver experience alone made up the difference.
You need an upgraded oil pan with swing arm for sure if you are taking any sweeping turns to protect the motor. Before buying my ACR I was running my GTS very regularly and pretty quickly with no problems. The mistake I made from a tracking point of view was putting the Roe on it. Plenty of guys will tell you they run a Roe with no heat problems.......sure. Not in the Texas heat and not going all out for 20 to 30 minutes. If you are just going 60% you'll be fine. If you are trying to run down the next car constantly you will get too hot in the summer.

I still have the stock suspension on mine, no aero. She became fussy as I pushed the limits to keep up. I didn't mind because the threshold is predictable and easily corrected. Your comfort level would probably be much higher changing up the suspension and then looking at the aero. Depending on the track gearing can make a huge difference. I run 3.55 gears, big brake kit, aggressive alignment, 305 and 335 18 inch kuhmos with necessary safety equipment. I had the car conservatively tuned to 550 RWHP for the track. I would think this is the RWHP you will need for a larger track if you hope to keep up. I would save any additional HP for last though!

On my home track I have run even with new ACRs with reasonably experienced drivers but one very good driver here in Houston just ran away from me....come to think of it he still does just not as quickly! I will say that 2 weekends into my ACR I was running 7 seconds faster than I ever did in my GTS at Texas World with a lot less effort. Once I drove an ACR I was hooked.

Running with an ACR with your current setup can be done at many tracks if you are a better driver. Be prepared to work on the car more than the gen 4 guys between sessions as well as between weekends if you are going to go the HP route to make up the difference in times. My 2 cents: DO NOT GO FORCED INDUCTION and concentrate on:
1)Good breaking, looks like you covered it.
2)Good rubber/wheels with decreased unsprung weight...the biggest jump in performance for me occurred with this step!
3)Suspension: A good alignment and changing your compression and rebound go a long way.
I WOULD THINK THE AVERAGE FELLA WOULD STOP HERE UNLESS YOU ARE REALLY ********.
4)Think aero at this point if you are really still needing a bump up in performance. You may find if you get more seat time that the average ACR is running the same lap times as you.
5)Get some more ponies NA if you are trying to keep up with experienced driver's in their ACRs.

If you want nitty gritty details just ask. Most of what I did was following the advice of Jon and Russ at Archer. They never steered me wrong. Good luck. Trust me, the only thing better that making an ACR driver sweat by keeping up with them in a gen 2 is passing them! Granted, that only happens with a significant experience difference. The weight and aero work wonders in the ACR.

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I have been debating over which Viper to get to meet my wants for the last 3 months. I've gone from gen II, to gen III, to gen IV and back the other way while mixing it all up. This last week I've been thinking that an ACR would satisfy my wants better than any other Viper, but was never sure I would feel necessary to pay $10K more for an ACR. The looks just about had me set on an ACR, and this post got me hook line and sinker. Maybe you should be put in charge of selling the remaining new Vipers so Dodge can reveal the new viper without sales losses. I hate the waiting game. My Viper savings account is open and filling up, but I still have to wait until next year. The waiting is killing me.

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plumcrazy said:

DaveGF, did you post your mods ? if not, would you mind and the weight of the car.

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ViperJon said:

This has been one of the most interesting threads in a long time and it's great to hear from some ******** racers who really put their cars to the test.
I love reading this stuff. Keep it coming.

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DaveGF said:

The engine is N/A and close to 800 HP at the crank. Top feed injectors, individual coil pack at each cylinder and MoTeC engine management. Stryker heads, forged bottom end, dry sump, Tilton clutch. EMCO sequential box integrated with the MoTeC for no lift, no clutch upshifts. Big front splitter, rear wing and rear diffuser. Flat bottom. Penske 3-way adj shocks w/ EMI Racing suspension mods. 345 Hoosier R100s rear and 315 R100s front. Fiberglass hood and doors. Windshield and back glass are Lexan. Brembo brakes with Snake brake ABS. 2,900 pounds, wet except for fuel, no (fat) driver. Jeez - seems like I ought to be faster!

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DaveGF said:

Hey Bill. That was me. You are correct on the time difference - more like 1/3 sec, not one to two (the memory is the second thing to go!). Ben actually did 23 laps, not 5. The five laps entry is how far behind he was due to him having a tire blow with five laps to go. The relatively small margin of victory (12 seconds, not 5), was due to a caution somewhat over halfway throughout the race. I was leading by Ben by about 25 seconds at the time of the caution - despite having started last due to our mechanical problems Saturday. Totally different cars though. I think Ben is a faster driver than me, we will see in the Viper Cup this year.
The Gen II is sorted a bit better now. At Hallett a month after TWS, it was just over 1 second faster than the fastest ACR-X.
To be clear, I love the ACR-X and look forward to participating in the Viper Cup this year. The Gen II is just a labor of love for a really cool track car that is only justified on that basis, not economics and not as a car with a large class of competitors like the X.
I think the X could surpass My Gen II with some fairly inexpensive mods targeting weight (no lead added as Viper Cup cars have) and lexan instead of glass. Throw in gearing changes and I think it would be right there.
Dave

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NI-KA said:

DaveGF,

Which differential and ratio?

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DaveGF said:

The engine is N/A and close to 800 HP at the crank. Top feed injectors, individual coil pack at each cylinder and MoTeC engine management. Stryker heads, forged bottom end, dry sump, Tilton clutch. EMCO sequential box integrated with the MoTeC for no lift, no clutch upshifts. Big front splitter, rear wing and rear diffuser. Flat bottom. Penske 3-way adj shocks w/ EMI Racing suspension mods. 345 Hoosier R100s rear and 315 R100s front. Fiberglass hood and doors. Windshield and back glass are Lexan. Brembo brakes with Snake brake ABS. 2,900 pounds, wet except for fuel, no (fat) driver. Jeez - seems like I ought to be faster!

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plumcrazy said:

Drumr, why do blow those trans's ? ever try the gen4 ?

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REDSLED said:

Yes, why are you blowing the trans? I'm running 550 RWHP and have had good succes wit the stock transmission. Are you losing 5th gear? That seems to be the weak spot if you have touched the ratios in the differential as extended runs on straightaways in 5th gear does tend to cause that cluster to grenade.

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DrumrBoy said:

Plum and Red, not sure why it happens, I generally lose 5th....sometimes after only 5-10 hours (hard hours mind you, but that's not alot of time).....and thenn a few others go away too. I haven't tried an Gen 4 though I recently blew up a well-built Gen 3..........I wasn't even shifting at the time. I went into 5th on a long straight......stayed on the throttle for 2-3 seconds and boom.

There's one turn on one track where I don't match revs....have to go from 5th to 3rd, 155 to 60 very fast....was thinking this might have strained 4th and 3rd....but its generally 5th that lets go.

Any thoughts are welcome. Going to try a G-Force next....ut maybe ought to go straight to EMCO or another brand of dog-ring sequential.

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99 R/T 10 said:

This is probably a similar situation that the guy s that run the mile event run into. Under heavy acceleration, the oil will tend to drift to the back of the transmission and the lubrication needed goes away. I think a few people have had external pumps installed to augment the lubrication and keep the trans from blowing. There is more info on the modification over at Viperalley.

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DC Performance said:

5th gear failure is a common issue for cars that run at high speeds, primarily on the track. A transmission cooler is the best way to improve lubrication to the 5th and 6th gear sets. These gears are the furthest from the lubricant and are prone to heat failure under hard use and high G-loads (which pulls the lubricant away from the gears). When we have a transmission setup for a cooler we have the oil return path go onto these gears.

For a streetcar that competes in high-speed events (like the mile or Silverstate) the complexity of a cooler and pump may not be needed. If you make big power, you may want to upgrade your transmission for higher loads as well as heat. First off, there are numerous updates to the original T-56. If you make big power then the later Gen 3 or 4 transmissions are the choice, the SRT Ram transmission is the most durable. Better syncros, shift forks and shift pads are common upgrades. Gear ratio changes to fifth and six gear are common- this lets you use 6th gear for top speed and makes the rpm drop in the upper gears much closer. One thing that will extend the gear life (5th and 6th primarily) is to have all the internal parts micronite finished. This is a chemical coating that will reduce heat in the transmission dramatically.

DC Performance and other vendors can provide transmission upgrade services. For transmission related issues or questions, feel free to call us.

Hope this helps.

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DC Performance said:

5th gear failure is a common issue for cars that run at high speeds, primarily on the track. A transmission cooler is the best way to improve lubrication to the 5th and 6th gear sets. These gears are the furthest from the lubricant and are prone to heat failure under hard use and high G-loads (which pulls the lubricant away from the gears). When we have a transmission setup for a cooler we have the oil return path go onto these gears.

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