hello to all that read this. I have been a member here for some time, but never post much of anything, but now it's time for the sinking of the money into the car. so, here's my question. I have a 91 RS 305 TBI (like everyone else) and as far as i know the tranny is an M5 from what i have gathered from other sites, but needless to say, it's a 5 speed automatic. im going to be beefing up the motor and would like to know how many pony's the tranny can take. i would like to stay with it, since it is a decent 5 speed, but if it can't take over 300HP ill have to do something different. but if anyone knows if the trans. can take decent HP or no. thanks!

 

M5 isn't a model of transmission, it's just an abbreviation for "manual 5 speed". The transmission you should have in your 91 is a "World Class T5". If you don't abuse it, it could last quite a while. If you beat on it though, then not so much.

 

It's not a 5 speed Automatic.

If it's a typical 3rd Gen 5 speed Manual, you could do a lot stronger than a T5. It may last if you're easy on it, but a T56 out of a 4th Gen car would be much stronger.

 

OK, seems as though my translation here got a little messed up, what im asking is how much HP can a stock tranny hold up. I'm looking to build my engine to around 325HP or theres abouts. will the stock tranny keep up with that, or will i need to buy one that could hold some power.

 

im confused, is it a manual or automatic, you said 5 speed automatic which are counter-intuitive to me.

the 88+ world class T5 manual transmissions "5 speed" can handle a little over 300 lb/ft of torque, you can whomp on one that doesn't have any problems, all day long with a stock 305 TPI and you'll be fine. TBI won't even hurt it at all. Chevy intentionally did not pair a T5 with a 350 because it didn't have a high enough torque rating for them to garuntee it not breaking under continuous and repetitive hard launching.

if its an automatic transmission i THINK its a 700r4. 700r4s can handle anything reasonable up to prob 700-800hp or torque.

 

well, the thing im scared of is i don't know what tranny it is to be totally honest with you. everyone sez that my car came with a 700R4, but it has an overdrive making it 5 different gears. i know the thing can take what i have right now, but what i have ain't much at the moment. if i move into the 300HP ground with that tranny im scared i might chew it up. again, if im not making any sence it's mainly because i have taken advice from people that don't know that much about the car, so i decided to take this route with people that have worked on them before. so, in any event, if i have a 5 speed overdrive automatic trans, can that take 300HP?

 

heres just a tip of the language people are used to hearing

if your car is an automatic with overdrive you don't call it a five speed, you call it a 700r4. when you say 5 speed people immediately think T5, or 5 speed MANUAL transmission. so never say 5 speed in reference to automatic, it just trips people up, as it did earlier in this thread. they all think you have a manual tranny, when infact, you have a 700r4 automatic tranny.

700r4 can easily withstand 300hp

 

heres whats messing with my head though. if it's indeed a 700R4, and help me if im not hearing this right, but the R4 means that it's 4 gears correct? do i have a 700R4 overdrive?
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and ill work on my messageboard lingo

 

No, it has an overdrive making it four different gears, not five.

 

yap, what he said

1, 2, D, [D]

is 700r4

 

ok, starting to get the picture here, but why is it when i go down the road, i can count 5 different gear changes? keep in mind that my knowlege of trans. isn't all that much, i know the basics of how they work, and believe me, i can tell you what doesn't work

 

You're mistaking the torque converter clutch locking for one of the gears.

 

ahhhh, now i understand, tanks! at least thats one aspect of this car that makes sence to me know. tanks ya'll vary much!