Chip For GTS

[zane11]

Does anyone know anything about the chip for the gts that improves your cars performance.

My dad is looking into one, what is the price for one and how much horsepower and torque do you gain ?

[Viper 10]

It doesn't exist. Viper ECU's do not have interchangeable chips (like other cars). The ECU's actually do very little work outside of engine management. Sean Roe makes a product called a VEC that has some adjustability to the ECU. Mopar Performance also sell the competition ECU out of their catalog.

From what I have heard on both of these products, they do very little in terms of performance.

I hope this answers your question.

Brad

[zane11]

Yeh that sux really bad. Yeh that does help too, but when u say helps very little how much is very little ?

[Viper 10]

Little enough to mean that it is not worth the money. The improvements were not something that you would even feel in SOTP performance. You might see a negligible increase on a dyno pull and that's it.

If your dad's Viper is more heavily modfied, then you might see more of an improvement. If you really want to read more on it, go to the Viper Club web site discussion forums and do a search on Mopar Performance ECU or Sean Roe VEC-1.

I would save your money for other mods. What does your dad have on the Viper now? Has he ever attended a high performance driving school? This is probably the best money that can be spent on a Viper (IMO).

Brad

[zane11]

Well so far just an exhaust but wants to do more. Whats the best thing to do to it for performance

[Viper 10]

Zane:

The best go mods are probably exhaust (with hi-flow Random Tech cats), headers and rearend gears. The best set up for SOTP gratification are 3.45 or 3.55 gears. Don't go any lower than this or it will effect stability of the car under heavy throttle.

I would also recommend that your dad upgrade the brakes on the Viper. It is probably the biggest shortcoming of the Viper. I would highly recommend Stop Tech front brakes (the rears have almost no stopping power).

Tell him not to go into the internals of the car or it will effect the warranty and the reliability of the car.

I hope that this helps.

Brad

[CarFreakBenP]

If your dad has $55,000 laying around, i would say that he should put the hennessy Venom 800 kit on it, that would make it run about a 10sec. flat 1/4 mile.

[Viper 10]

Originally posted by CarFreakBenP
If your dad has $55,000 laying around, i would say that he should put the hennessy Venom 800 kit on it, that would make it run about a 10sec. flat 1/4 mile.

You obviously haven't heard the latest on your hero John Hennessey...


Hennessey Update Link

You give Hennessey your money and you'll never see it again...

[CarFreakBenP]

Hmm..... I guess i haven't been doing my homework as good as i should have, that's the first time that i've heard that. Is there another company that produces Twin Turbo kits for the viper? Thanks for the update I probably wouldn't have caught it.

[Viper 10]

Originally posted by CarFreakBenP
Hmm..... I guess i haven't been doing my homework as good as i should have, that's the first time that i've heard that. Is there another company that produces Twin Turbo kits for the viper? Thanks for the update I probably wouldn't have caught it.

I would be very careful when considering doing a twin turbo set up on a Viper. First off, the Vipers after late '98 came with hyperreutectic cast pistons. These pistons were not made to withstand heavy boost or things like NOS. It would be a very expensive rebuild if you blew a piston or threw a rod.

Secondly, Vipers are difficult to turbocharge becasue of the limited amount of space to fit decent sized turbos underneath the car, On top of this, the floor pan in a Viper is made out of fiberglass and can easily catch on fire (i.e. SVSi Stryker).

Another reason is the lack of space to adequetely intercool the turbo's. A turbo or supercharged engine will lose in the area of 50% of it's power (increase) when the engine hits running temps (without an intercooler).

Finally running turbos on a high torque engine will cause some real probems driving a Viper in anything but a straight line. When the turbo hits it's sweet spot, the combination with high torque could be fatal for the average driver. Traction becoem a very serious problem.

Blowers tend to be simpler to install and more condusive to higher torque engines like the Viper's.

JMO.

Brad

[CarFreakBenP]

Viper 10, how much hp would a viper run with a blower and bolt on mods? And also in your opinion, how much hp can u run in a viper "safely"(straight line, and cornering)? Thanks for the info.

[Viper 10]

Originally posted by CarFreakBenP
Viper 10, how much hp would a viper run with a blower and bolt on mods? And also in your opinion, how much hp can u run in a viper "safely"(straight line, and cornering)? Thanks for the info.

Car Freak:

I'll answer your question from a couple of different angles.

First off, how much HP can you get from a blower on a Viper?

On straight blower you can get up to about 800 RWHP on Vipers. If you add NOS into the equation, you can get 1,200 HP from a Viper motor. Can you drive this car daily? Not likely. The Le mans Vipers are turning around 800 HP (that has been heavily restricted with reduced intake).

How much can you run on a Viper safely?

I would say that on a stock Viper chassis that you can run up to 700 HP before the chassis is compromised. Anything beyond this will cause a significant amount of chassis and suspension flex, and will diminish the car's handling characteristics.

What does this mean?

It means that if you were drag racing the Viper, that the chassis flex (combined with th eengine roll over) would cause the car to vear off track (mostly to the right), and cause the loss of traction. This is due to the amout of torque the Viper lays down.

On a road course, this would result in the loss of traction (once again because of the huge amount of torque through a very wide power band) through the transitions, and the result would be loss of traction and most likely a spin out (or in a worse-case scenario the car would do a snap 180 degree spin).

Does this mean that the Viper chassis is inadequate?

Absolutely not. It is one of the stiffest chassis in the automotive industry. I have heard from a friend of mine who has raced in several ALMS events, that half of the privateer Vipers entered are actually street cars that have been converted to race cars (Chamberlain Racing s a good example). So the difference between the street version and the track version of the Vipers is closer than most realize. This can't be said for other cars.

I hope that this answers your questions sufficiently.

Brad

[CarFreakBenP]

Brad, if you put a posi-trac rear end in a viper do you think that it would be able to handle more? Thanks for the information.



, Ben

[Viper 10]

The car already has a Dana Super 44 limited slip rearend on it (which essentially means that the internals are from a Dana 60 in an aluminum casing). The Dana 60 casing is better suited to the punishment of racing. If you went and replaced the entire rear suspension with a solid 4 link, you would definitely have a better set up for drag racing. Even with the Dana upgrade, it is still only rated up to 800 HP.

If you swapped the rearend diff to a Quaife or Hewland rear end diff, it would optimize the road racing attributes. An upgrade to a sequential tranny from the same manufacturers would maximize the formula. These are the drivetrain components used on ALMS and Le Mans Europe Series.

Most people on the street would even know about these upgrades (which is why Levin, hennessey, SVSi, TNT and others can get away with minor upgrades. They know that most of their customers will never go to WOT on these cars, or question their "expertise". If they customers went to the performance potential of these HP monsters, they would very quickly find out how important chassis and suspension are to these cars. Unfortunately, all of the major tuners out there are mainly engine guys and drag racers.

IMO, there is plenty of room for a credible tuner that can doo the chassis, suspension and engine for a total package. The stuff that is out there today can get you killed very fast, because most of the people that can afford these tuners (spending anywhere from $110k to $250k on their cars), don't have any clue how to drive the finished products.

Brad

[CarFreakBenP]

Brad,
If you don't know how to drive, a bone-stock Viper is enough to get you killed. Thank you again for the info.
P.S. Do you happen to know anything about the Mitsubishi 3000GT VR-4?

,Ben