2001 engine upgrade

[carl B]

I want to run a good shot of NOS and understand the way to go is to change the pistons to the earlier variety

I guess these are forged

Any other advice?

Thanks

Carl

 

[STUGOTS]

Call Sean Roe he has a piston upgrade for creampuffs and is a direct replacement.

1 866 275 7326 3#

 

[carl B]

Well it looks like that is the way to go I guess

Is there any other Jobs I could do while the motor is torn down??

For instance I beleive there is a baffle for the sump?

Carl

 

[RedGTS]

It would definitely be worth upgrading your lifters to some that won't bleed down like the stockers. They aren't too expensive, around $250-300.

 

[GTS Bruce]

Baffle and acr oil set up a good idea. Bruce

 

[STUGOTS]

**** do heads while shes torn down.

 

[carl B]

well I am going to order the pistons from Shaun this week I guess

Carl

 

[v10kingsnake]

how much nos are you planning to throw into the block. your car could handle 100 safely with the current setup but any more plan on going the current route

 

[Russ M]

Nitrous or any other power enhancer does NOT require forged pistons. It is nice to have them because they are capable of withstanding more heat/detonation but there are many other parts worthy of your attention rather than the pistons.

The #1 problem with Vipers and performance mods is Fuel/ignition. If you setup a nitrous kit with proper fuel control/octane/supply there is no need to worry about installing forged pistons.

Ignition is very nice to control as well but unless you want to spend money on an AEM unit, you wont get the desired control.

 

[RedGTS]

Nitrous or any other power enhancer does NOT require forged pistons.

As a blanket statement, which this is, it's false, because it implies that forged pistons are more of an insurance policy "just to make sure" and that they don't frequently break, without reference to power output or boost levels. If you meant to say you can run a moderate shot or moderate boost on a properly setup car relatively safely (with the emphasis on all those adjectives and adverbs) it may be true. There is a reason no major tuner will use cast pistons for a high hp application, and there are numerous broken pistons serving as ashtrays that weren't the result of someone making a mistake (other than sticking with the cast pistons). In fact, many of them shattered with basic Roe or Paxton kits at 5 or 6 psi. They leave you NO margin for changed circumstances, be it a bad tank of gas, or a significant change in ambient temps, or a little oil blowby in the intake tubes, or a bad spark plug. I can't speak to NO2 because I've never used it, but I would never run more than a basic 5 psi blower system with cast pistons, and even with that you take your chances.

 

[Russ M]

RedGTS,

It is a blanket statement because cast pistons can and will do the job adequatly if everything else is as it should be.

The reason people have broken pistons, melted pistons, etc is because of poor fuel/ignition management in low to moderate power boosts.

There are many many cars out there that use the same type of pistons as creampuffs that handle much more power than Vipers for the same type of material.

Reason for aftermarket tuners to use forged vs cast is simple, why use something inferior when a beter product is available. In this case however its not about having to rebuild an engine anyways its about trying to run a descent shot of nitrous through a perfectly fine motor.

PS. Look at DLM's cast piston kits and see what power they produce, its all about have a motec and a tuner who can make it run right. The Roe/Paxton kits are far from ideal when it comes to proper engine control. Although the Roe is light years ahead of the paxtons fuel pressure bandaid.

 

[RedGTS]

There are many many cars out there that use the same type of pistons as creampuffs that handle much more power than Vipers for the same type of material.

Very true but in this case largely irrelevant. The problem with Viper cast pistons isn't so much that they're cast as it is the fact that they have very little material above the top ring land. DLM makes good power with some of its cast piston cars (although not nearly as much as its forged piston cars), but again, that hardly supports a general statement that cast pistons are fine. You can't use the fact that one great tuner on the planet for $20k+ can make decent power to support your statement that cast pistons are fine for forced induction Vipers generally. There are now far more people going the DIY Roe or Paxton route than the custom route, and I personally know or know of 6-8 different people who have blown cast pistons running the basic kits. And this is just people who have come up in conversations with people I know over the last couple of years without trying to identify such people. Common sense would dictate that those don't make up the total universe of people who have suffered broken pistons. Nor were they all the result of some "mistake" or owner error. I had a broken piston running the 5 lb Roe kit on 93 octane and my car had been dyno tuned by a very well respected tuner, and the a/f ratio was fine (I should add that I don't know for sure whether the piston broke before or after he tuned it, but it did ping some both before and after).

The point is, not everyone scours this board regularly like you and I probably do, and if someone reads a blanket statement like that and thinks that there is no real risk in keeping his cast pistons with a blower, he would be very wrong, IMO. Saying "if everything else is as it should be" is rather like saying they won't break so long as nothing happens that would cause them to break. IOW, there are simply too many "everything elses" that must be accounted for 24/7 for as long as you drive the car to make that a realistic situation, particularly in a DIY situation. Now if we were talking solely about Motec or AEM controlled setups installed and tuned by experts, obviously that would reduce the risk significantly. IMO using the cast pistons with any f/i setup involves a significant level of risk that the owner should be aware of and accept.

 

[davem]

[(I should add that I don't know for sure whether the piston broke before or after he tuned it, but it did ping some both before and after).

It bothers me a lot that you drove a SC car that had a pinging problem. This pinging explains your piston problem, as I'm sure you know. It's like hitting your pistons with a hammer. I am shocked that you had the car tuned by someone who let you leave with a pinging engine - this is absolutely unacceptable.

If you have forced induction and hear a ping, don't drive the car until you get it fixed. It does not matter if the a/f is correct. Is your car still pinging? If it is get your timing ******** some more and make sure your crankcase vent is not plumbed into the intake - oil in the air will cause pinging.

good luck,
-Dave.

 

[RedGTS]

Dave, I'm sure your intentions are good as would be most of your advice for someone who didn't know anything about these issues, but I already knew all that and it's not that simple. The car didn't ping all the time. It would do it occasionally, barely audible, at WOT high rpm only. I am told this was not an uncommon occurrence with the Roe system, particularly back then, but I can only speak for myself. I had it dyno tuned as soon as I noticed it, and it didn't ping at all on the dyno, so I didn't "leave with a pinging engine." But I noticed it again on a couple of occasions afterward, and Sean burned me some new cards to try to get rid of it. They seemed to help, but didn't get rid of it completely. Needless to say, I stayed out of the high rpm range anytime I thought I heard pinging. Rather than keep trying to tune it out, I had been thinking about changing over to a higher boost setup anyway and I decided to install forged pistons and a bunch of other stuff and switch to a Heffner centrifugal system. When the engine came apart we discovered I had a piston with a piece missing. Which brings me back to my point--I did everything I could reasonably do to eliminate the problem, and I still broke a piston. They just won't take any detonation, and a little detonation for one reason or another is not uncommon with f/i. My current setup doesn't ping, and it also has knock sensors so if it ever does it will pull timing immediately.

 

[davem]

Ronnie,
Thanks for the reply, my post was intended to inform other readers that may have seen your post. I assumed from you mods you know what your doing. But I felt that you implied that a little detonation is acceptable or common and I wanted to clarify this is not the case.

There can be no tolerance for detonation with forced induction- you either have it or you don't. If you have a little detonation that is too much.

Glad you have the car straightened out. Looks like your making great power.

-Dave.

 

[carl B]

Ok so I ordered the S/C and the pistons from sean

carl

 

[Neil - UK]

Blimey Carl your GTS has only just landed and your modding already you need to spaek to Nadine she also has the Roe S/C