My car is a DAILY DRIVER and that see's the track every week when is possible I also drive it to other tracks as BMP=100mile each way and Gainsville=135 miles each way so OVERDRIVE is a must I will not drive a car at 3500rpm at 55-60 mph for 1hour+ so a 3speed is out of the question for now although I know its stronger and will last longer but again its not a trailer queen, I also know that i could do a 400 with an overdrive unit or a 4l80 but the car already weigh's near 3700 race trim with out a cage so i have chosen to stay away of more weight for now,
If my car was a trailer queen and it will never be it would have a th400 or a glide
850 sounds close to a parts build for a good 4l60e I only said somthing because i was thinking he was asking for a rebuild to handle 600hp and you said you could do it for 850 or so i wasnt tring to bust your *****

 

There was a time and not long ago my car seen near 500 miles a week and at near 500rwhp it got 14mpg could you amagine that with a th400
Yes my 4l60e will break again but with that being said i think i put a 4l60 through more hell than anyone, My car with my wife driving is 3680 pounds and it cuts low 1.30's 60ft on every hooking pass, I spray a 2kit set up from between 200hp to 350hp for now through the shifts, almost 3 years ago i had clutch problems it was just time learning what clutches worked the best but sense then and over 2.5 years i have had no clutch failure in fact in the last 2.5 years i have broken 2 foward sprags due to a 10bolt rear going south twice before i got the 12bolt, 2 pumps that was my fault and one out put shaft. For a car that has made as many passes as mine and runs the bottom 6's with a best of 6.022 in the 1/8 mile a see know reason to drop the 4l60 yet, within the next month i will be replacing the heads and studs to up the n20 shot into the 400's that will be well over 800rwhp through a 4l60e
And for the record i had a 66 chevyII with a 434 smallblock witha lot of spray it broke 2 th400 and 1 glide car would run 5.50's 1/8 mile all night, Im just stating that even the big tranny's break

 

i agree i fraggged the bellhousing with my 434 launched at 4500 and all hell broke loose......the only thing i say in this whole thread eeryone builds ther trannies different my mentor right now that i call for help worked with Lingenfelter in the 80s Duane Watson and he is who i take my advice from......i now what i can buiuld them for and i guess maybe i am not skilled enough yet for a 4l60e 700hp but i am definatley going into the lab to experiment but again the parts are limited until you can get rid of that raggedy sunshell even the "beast" i have seen shatter

 

Since you guys are talking about all this hp and stuff, and the 4l60e not being sufficient enough usually.

I have a question. Is it the actual hp that breaks the tranny, or is it hooking with the hp?

Im wondering because if I have a 600rwhp car, and I run at the track, is it going to break because of the power the tranny is handling, or is it because the car is hooking and all that power is reaching the ground. I plan to be running on street tires for a long while. Im sure the day will come when im tired of not getting any traction and I start going dr's etc.. but for now when the turbo goes in, its street tires.

 

well it is actually the torque that does it and then hooking up......usually the sunshell and front sun gear will frag and then the rear planet or the output shaft.....they make a stronger sunshell called the "beast" its like 60 bucks and 5 or 6 pinion planets....i agree that they can be built to handle the power but its just way to much money when i could build a th 400 to handle 1000 hp for around 600

 

torque breaks mechanical parts. never "horsepower" as that is a measure of acceleration.

 

Dead hooking and a good tight converter will find the weak spots and the 4l60e has a few of them but the sunshell, planets all of these things can be built to handle the TQ they are not as weak as alot of people make them out to be it just takes a few more things that have to be done to them to make them stronger, The beast is no where near the best shell out there, but really the shell, planets, input and out put shafts are the EASY thing to fix, most of the time these parts are not the issue in tranny failure,
With 600hp and street tires the biggest issue is getting the 3rd/4th pack to live on 2nd to 3rd shifts, If the tranny isnt built right this will be your biggest prob on street tires.

Drive your car around in 3rd every where you go for the next 2 weeks if you can handle that by a built th400 it will only be slightly worse due to know converter lock up but if you cant take it like me find a good guy or shop that know's the 4l60e and theres only a hand full of them. 600hp is a walk in the park with a 4l60e IMO