No idea what the model number is on the auto tranny in the 03+ eco cavi's, but how much power can they hold before they start slipping?
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Team Gates
4T40E. regardless of what you'll hear they dont handle much abuse.
Loads... more than most people on here will ever hit. You'll likely snap the axles before the transmission.
There is no exact number... but I'd be willing to throw 300hp out there as a ballpark for ya...
Lenko, John Lenko wrote:Loads... more than most people on here will ever hit. You'll likely snap the axles before the transmission.
There is no exact number... but I'd be willing to throw 300hp out there as a ballpark for ya...
Is there a company that makes stronger axles or is there another car that has the same sized axles that you can use that are stronger to handle say 230-250whp?
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Team Gates
Yes summit racing has them, also jegs
kyle 102565 wrote:4T40E. regardless of what you'll hear they dont handle much abuse.
uhh sure whatever you say.... too bad there are quite a few people running quite alot of power through them. mine has taken all the abuse that i have thrown at it and i have had no problems with it
Derek Z24 wrote:kyle 102565 wrote:4T40E. regardless of what you'll hear they dont handle much abuse.
uhh sure whatever you say.... too bad there are quite a few people running quite alot of power through them. mine has taken all the abuse that i have thrown at it and i have had no problems with it
what do you consider "quite alot of power?" 250 hp?
GM is full of @!#$ lol like said it'll handle as much as the axles will ill bet and theres guys running around 300 whp on stock axles the biggest thing is keep the line pressure up (shiftplus or interceptor) and keep it cool and you'll be fine
The one, the only, ME.
remember any max hp on the ecotec is at redline or close to it. these people who have 300 hp arent running around at redline on the street, the majority of street driving is at 2500 to 3500 rpm and nowhere near 300 hp and hardly past GMs limits of what the trans can handle. running 300 hp at redline on the track will break the 4T40, eventually the sunshell will break on upshifts. higher line pressure will only keep apply pressures up and firm the shifts.
Kyle is right, the tranny was only designed to handle smaller motors.
You might get it to last longer on a boosted/nitroused motor if you blow off the boost/cut off the nitrous during the up shifts, but it would still be too much for that little tranny to put allot of trust in.
The 4T45E can handle about 15lb/ft more torque, which is a little better. The 4T65E would be a better choice, but the best bet would be a 4T80E. Problem is will the PCM software work with any of the other trannys. I'm sure the wiring and mounts could be made to work with a little fabrication.
kyle 102565 wrote:remember any max hp on the ecotec is at redline or close to it. these people who have 300 hp arent running around at redline on the street, the majority of street driving is at 2500 to 3500 rpm and nowhere near 300 hp and hardly past GMs limits of what the trans can handle. running 300 hp at redline on the track will break the 4T40, eventually the sunshell will break on upshifts. higher line pressure will only keep apply pressures up and firm the shifts.
First of all, you can't determine that every cars powerband will be at redline, before redline or after redline because it's all in what modifications you do to your vehicle and if your engine is modified, how it is modified.
Second, for you to say "X amount of HP will break the transmission" is foolish because you (I highly doubt) have ever done it or will do it. Do you even know any people who have the 4T40E transmission that is running on boost and high amounts of it?
It's people like you who spread propaganda about the auatomatic transmissions but can not point out any person experience or people who have had problems and what problems they experienced. Saying a transmission will break doesn't clarify anything. That's like if I was a mechanic and I told the customer that their motor just broke and didn't explain what happend, what broke or why it broke. Plainly, it sounds like a load of BS.
The only true problem that ANY higher power auto transmission will run into is heat and an transmission cooler will help with that problem.
Jason Adcock wrote:The official answer from GM is 190 lb*ft of engine torque...no mention of horsepower:
http://media.gm.com/division/powertrain/products/transmission/04_auto_trans_specs.html#mn4
GM is full of it. Listen, don't ever listen to any statistic that GM puts out because they are always wrong and they play it safe. They know that the transmission can handle more power BUT they'd rather play it safe than have people say "Hey you said my tranny can handle 250 HP but it went at 220 HP". They always downplay their parts. Here's another example. In the GM ECOTEC Performance Handbook it states that at 260 HP (Crank) the rods will snap and basing that as it's limit, yet I know people are are at the 220-260 HP point on a stock bottom end...oh by the way...WHEEL HORSEPOWER.
John Lenko wrote:Loads... more than most people on here will ever hit. You'll likely snap the axles before the transmission.
Exactly.
And for anyone who thinks I'm being some loud mouth or all talk and no game kind of guy...well, give me till January, I will be turbo'd running a T3/T4 turbo at around 7 psi, I already have a modified motor (rebuilt head) and a month or so after that I will be running 9:1 compression with much more PSI. Oh yes, this will be on a stock Auto Transmission just so I can prove my point.
Peace Out.
www.kronosperformance.com / 732-742-8837
By the way Justin, I see you have an ECOTEC...if you need more tips and locations on where to find parts, read the sticky I wrote:
The Full ECOTEC Build Guide
Good Luck.
www.kronosperformance.com / 732-742-8837
actually i'm a torque converter rebuilder along with being a automatic trans builder, i've been in the automatic trans business now for over 12 years with full experience in building automatic transmissions along with manuals. 20 percent of our business is full race applications. prior to getting into automatics i was an engine builder for 3 years along with being a class B mechanic since the age of 17. its general knowledge that any engine especially a 4 banger stock making 140 hp with power adders maybe making 250 to 300 hp doesnt make anything close to their max power in street driving from 2500 to 4000 rpm. their max power IS at redline or right before. at 5252 rpm torque and hp intersect, with torque dropping off and hp rising to its max, (redline on the ecotec is what 5700 rpm.) thats etched in stone and goes for any gas piston engine on earth. the entire trans industry says the same thing i do about the 4T40, ive seen a half a dozen 4T40s in the past 3 months blown to hell all in late model cavies stock engines other than simple bolt ons. how is that propaganda?
Quote:
redline on the ecotec is what 5700 rpm
Redline is just under 7000 RPMs, about 6800 RPMs.
Quote:
ive seen a half a dozen 4T40s in the past 3 months blown to hell all in late model cavies stock engines other than simple bolt ons. how is that propaganda?
And were those of high horsepower or high mileage vehicles? What exactly "went" on those transmissions? Seriously, that could be said the same with a manual transmission, not every stick car is going to survive up to a certain amount of power, you have your good ones and bad ones but generally they can handle it and so can the autos.
I'm not saying that our transmissions are some invincible or increbly amazingly build transmission but I'm saying that they can handle more power than people give them credit. Also, I can say this because I know someone who is turbo'd running more than 200 whp and he's been running high amounts of power for years now.
But whatever, you believe what you want, you have your "experience" under neath your belt and you're entitled to your opinion but when I come back around in January or February with Dyno Sheet #s putting out over 200 whp, then maybe that'll change your perseption.
www.kronosperformance.com / 732-742-8837
Stock 4T40E with Interceptor, 255.7whp and 211.33 wheel torque. Not broken yet.
- 93 mph in the 1/8 mile
Member of J-Body Of Michigan.
I could run 13.8's all night long on my 4T40E.... 85 hp shot of nitrous with 94 octane fuel... stock trans, but with an aux cooler... Interceptor at full line pressure... M/T 15" slicks...
I didn't break a damn thing... and I bet you $20 I was harder on that trans than 99% of the people on this forum.
Factory freak? Maybe... you tell me.
Skilz10179 wrote:Stock 4T40E with Interceptor, 255.7whp and 211.33 wheel torque. Not broken yet.
Thank You
www.kronosperformance.com / 732-742-8837
i'm with NJHK, im out to prove what it'll take myself, but i'm going N/A, and im sure it'll go well into the 250 whp range with no issues
The one, the only, ME.
Davide wrote:NJHK (Sexual Chocolate) wrote:Skilz10179 wrote:Stock 4T40E with Interceptor, 255.7whp and 211.33 wheel torque. Not broken yet.
Thank You
255???????? DAMN
Read his profile and you know why he's running such good #s...
www.kronosperformance.com / 732-742-8837
i can agree with most of you saying the the autoo 3spd will handle high rpms and high power, ive had my 97 z for abour 4 years know and it has seen a lot of high redlines, and is running avery day just fine. iam also dont have trans interceptor or cooler just stock. and just look at some of the guys on this forum..skilz,lenko they are autos and high power ...do-n just fine...just my 2.5 cents....
