I am looking into modding my car. I have a TR224 / TCI 3500 right now, and have plans for lt's, ls6 intake then heads. As I am thinking more about it, I have been thinking about FAST intake, bigger cam etc. Then I realized I could be putting out over 400rwhp - sounds like the stock a4 wouldn't take kindly to that! Would for some reason the TR224 be more gentle on the stock a4 than the TREX? What are your thoughts?

 

what causes A4's to break?

1.) RPM's
2.) power
3.) heat

probably in that order. if you run that through a stock A4 with STOCK SHIFT POINTS, it may last a while. if you run that through an A4 with shift points over 6,000 rpm's, i give it a week.

 

umm i would say heat more than anything and miles ofcourse! keep good fluid! but as for the statement above with shiftpoints over 6000! mine are at 6800 and i have 40 passes or so on the car and i daily drive it! just keep good fluid in it!

 

i wouldn't. heat is only an issue with an aftermarket stall converter with no cooler. in his case, it's going to be the RPM's that rip his 4L60E to shreads. putting a heads and cam package on an f-body and upping the shift points to 6800+rpm's are known to fry the stock 4L60E's the very first WOT run. again, i'm willing to bet money that RPM's are the 4L60E's worst nightmare.

 

I've got several friends running high RPM's (H/C) through stock trannies and zero issues. Does it contribute? I'm not saying it doesn't, but my personal experience is no. It takes more than a theory to convince me. Heat is an obvious killer, but like Choco said, that doesn't really become a factor until you introduce a TC.

 

Heat is a long term minor issue , torque and rpm are the killers , heat will eventually harden seals ect but thats all

 

i was talking about an aftermarket TC! sorry! but i can see how the rpm's can cause transmision failure i just havnt experienced it yet! lol and hope i dont soon!

 

the point i'm trying to make is that a stock trans probably runs hotter than a stalled, cooled trans. stock trans are known to last 100k-150k miles in a bone stock or near stock f-body all the time, so the point i'm trying to make is, if your car has a tranny cooler on it, heat shouldn't be much of an issue for you, at least no more of an issue than it is for a stock trans, and they are known to live well past the 100k mark.

now, you'll be highly modified, so heat should be the least of your worries. your biggest worry is RPM's for sure, then power. just note that the higher in the rpm range you make your power, the sooner your 4L60E will go boom. it's not unheard of for it to start slipping after a single, solitary WOT blast.

make sure you have the money for a built tranny before you get this done. IMO, you should get a tranny before you even do these mods. that way, you can sell your stock 4L60E to cut the costs or you can keep it around in case the built one goes in the distant future.

 

Ah allmost a qoute of my common statment , tranny is the foundation if i was doing a build up it would be my first move not as glorious or fun but sure makes the mods more fun when its not dying the next day

 

it's heat, I know many a4 ls1s that have raised their shift points and are doing fine so far.

 

Mine lasted one day after I had my cam installed.

 

Mine has lasted with a 4K stall, Trans Go shift kit, and tranny cooler. I spray 200hp out of the hole and do not spray through the shifts. The shift rpm is set at 6800rpm. I know it is just a matter of time before it goes. But I don't care. I want to get all I can out of this stock tranny before I drop 3K for a built one.

 

so why are all aftermarket trans rated in hp. its not the same. (well lets not get into the logics of it) but rear wheel tq thru the right stall will be higher than hp...

as long as you have a cooler, heat is not an issue. rpm's are not an issue. its torque and time. ive heard of people with a 4000 stall spraying and the tranny lasting two years. ive heard of stock ones going out. just a matter of time.

 

shifting at 6800 will not only kill your tranny but your stock shortblock as well..

GM only rates them at 6000 rpm to...

 

i got 2 hard years on my stock 4l60e,tic rebuild kit got 6 months now im gonna go with a flt or performabuilt

 

no sir, speak to a trans builder. rpm's are far more deadly than heat. rpm's are the reason why 4L60E's break a few days after a h/c package. heat can't possibly do that. that causes long term damage.

 

So how do you explain the multitude of people who have spun their stock trannies to 6500-6800 RPM's with no issues whatsoever? Granted, there are people who have done it and blown the tranny almost immediately, but enough have had success going against what you are saying. I don't believe the proof is there. And many builders stand by the heat argument. How long do you think a stalled tranny without a cooler will last? My bet is much shorter than a cammed A4 that spins to 6800.

 

I personally think DRIVING HABITS break a4's more than power or rpms.....stock engines tear up trannies when the wrong person is driving....I have made well over 500 rwhp on N20 and stock trans....In other words....driving 50 mph and nailing it while the tranny drops from "lockup" down to 2nd. equals HUGE stress load on clutches and rest of internals..or doin a "top end" run...shifting from 3rd to 4th gear under WOT at 130 plus equals toasted 3-4 clutch pack....never changing fluid...etc.. Not saying that a stock A4 will live forever behind 500 plus hp...and 4000 rpm launches but knowing how the tranny operates and responsible care taking will definantly increase the life of it....

 

luck and nothing more. no tranny is put together the same and there is always an exception to the rule, no matter how few. RPM's are still the #1 killer no matter how you roll the dice.

it's also important to note that they may not be going WOT much. you're only going to touch those 6000+ shift points when you go WOT. if you never race your car and never go over 6000 rpm's, it's not going to matter.

we're not talking about a stalled tranny with no cooler here. few people on these boards are stupid enough to do that, so that isn't the issue here.

proof of this is that there are plenty of people making 400rwhp with a forced induction setup and stock shift points and their tranny lasts a while. talk to the FI guys. a cammed car with raised shift points and a lesser rwhp rating will kill a 4L60E faster than an FI guy making more rwhp and stock shift points.

 

Heat is a slow killer. RPM and torque are instant killers. Get a part that is just barely within manufacturing tolarance and load it with more force and spin it to 6800 and watch it fly apart. Like Choco, I have had trans builders tell me that going over 6400 is really tough on them.

Based upon my experience, I think it is torque that is the bigger killer. You see guys on the spray with a stock cam chew up these trannies and they're not spinning higher than 6200. I think you see more burnt clutches and trashed bands then hard part breaks. Guys with stalls and drag tires are really loading the drivetrain.

The final killer on H&C cars is tuning. Improper line pressure resulting in too little or too much slip burns clutches or adds shock on every shift.