LS1Porch

I agree that a extra few thousand bucks in the beginning of a v8 swap will go a lot further in the end, but keep in mind that these cars just don't do well with a whole lot of extra power. First you have to deal with tires spinning, then axles breaking, then transaxles breaking, then what (driveshaft? coupler? input shaft?)?

My point is--I, personally, do not think these are a good car to get power hungry in. They're plenty fast with 400-450hp, but beyond that you're probably better off building a Corvette or something that can handle the power.

But, don't let me stop you from building a 550hp dry-sumped n/a monster!

95ONE

Axles only break from trans movement. Problem fixed. Tons of LS1 transmissions have lost their lives to any kind of quarter mile abuse.. They are just not as expensive to fix.

TonyG

I've never broken an axle. The only transmission problems I've ever had in 10+ years of tracking 951's with high HP turbo 4's and V8's were synchro related (which is from age) and the stock LSD carrier, which is not 1 piece but several welded together. I broke one of those, which took out the entire transmission.

Now I have a Guard LSD which is one piece and won't break.


TonyG

LS1Porch

Yeah, but you're in the 400-ish range that i'm saying is safe (and plenty of power). My point is that if you start getting greedy, moving up towards 500rwhp, you may not be so lucky.

There are solutions to all these problems, but personally i'd rather go to the track with a 400hp car that's dead-reliable and well balanced than a 500hp car that's constantly breaking stuff and can't get traction until the middle of 4th gear. That's just me though...


95one--that's not necessarily true. There are a few people on the swap forums who have had axle issues with a solid trans mount. The stock axles on these cars are not very beefy.

968ls1

I disagree that 951 axles are not beefy in 14 years of driving V8 conversions I have never broken a quality 951 axle and I say quality because there is a difference. I do feel that 500whp is about the max for reliability and would only be useful in a track application with 315 or 335 rear tires. I have seen more Cup Car axles fail that 951. I know of two car that are tracked regularly that make 450whp without axle issues. Quality components serviced regularly will hold up but you have to be willing to spend the $$$$!

TonyG

I now run the GKN Motosport cv joint/axles "just because" ... but I never broke a stock cv joint/axle.

And I agree... I've seen several 996/ track cars with broken cv joints.


TonyG

eclou

When you say "quality" does that include the factory stock units? Or is there something aftermarket you are referring to? I would be interested to know your experience since you probably have more time with these hybrids than anyone else

arthropraxis

I remember reading something related to the rebuilt axles after being cut lose their temper(hardness) that the new ones have.

2bridges

Well contrary to those that have posted above I can say I have had two 951 transmissions failures with 350 and less rwhp.

LS1Porch is right on in my opinion.

I very seriously considered a blower LS motor tranplant in my 951.... the only way I figure it could be made to live would be a complete trans/diff transplant from a C5.

In the end I went with a 550RWHP blown Z06. I would wager a 951 trans would not live one afternoon behind this LS... now way no how.

968ls1

When I say quality I mean factory new CVs not rebuilt crap from Autozone. If you buy complete axles from World Pack they do not come with 951 CV's they will have standard 944 non-heat treated CV's that will fail. The GNC axles Tony has are the best offered but hard to come buy and expensive. If you want quality axles buy 951 specific CV's and put them on your axles. How you drive and treat the equipment has a lot to do with the longevity and if you have a high mileage gearbox that has gotten out of spec it will be prone to failure. I base my comments on many years of experience and real world use on the street and track. If you are failing 951 transmissions with less that 400whp they were either not in good shape to start with or you are abusing them. At 550rwhp you might be right but until you go there you really don't know.

TonyG

And...... I have the last set sold by SSF on my car now.

Many people have contacted me asking where they could get them or if I wanted to sell mine.......


I guess for someone to get mine... they'll have to buy the whole car


TonyG