I have had horrible luck with my 700r4 tranny that is currently in my car. Two summers ago I put 2500 into it to rebuild it. Then this past summer it decided to take a dump on me again just after the warranty ended. So this spring I am thinking of just buying a whole different transmission. I found this website that has a whole host of different trannys. I have two questions.

1) What would be the best tranny for my car, in your opinion and why? (I have a 1986 IROC-Z with a stock 305 in it with future plans of upgrading to a diff motor)

2) On some of the trannys I've looked at they give HP ratings, if the tranny says it will hold 500 HP would I be able to stick that behind my 305 that pushes 200 HP and be able to play with it without much worries?

Please, constructive responses only. Any and all opinions are appreciated and will be taken into consideration.

Thanks,
Shane

**Edit**

Automatic tranny for now

And I wasn't even beating on it. I was at a stop sign. An took off from it at a slow pace. Got to 10 mph and I heard a bang and I couldn't go anymore.

I don't know exactly what happened. But, I called the people and he said the best he could do was open it up for free and look it over. And go from then.

And I get on the gas a little while driving around town but its nothin too great bc it's not that powerful. An I've ran it down a drag only twice.

 

All depends what you want. You never specified if you want auto or stick. All transmissions have their plus's and their minus's.

 

Here you go. top of the line products from gear star ... that if you stick with a 700r4

http://www.gearstar.net/transmission....php?catunid=6

 

If you blew up a rebuilt 700r4 with a stock 305, then something is wrong. Either it's the way you are using it, or the people that did the rebuild. Lots of people including myself are running stock/stockish 700r4's behind much more powerful engines with no issues.

I would say that either you got shafted on the rebuild, or you did something to overheat it. Did you try giving hell to the people that rebuilt it? I sure would.

 

what went wrong with the 700r4s? my 700r4 has been very good-got it for $150 out of 85 caprice and clapped a shift kit in itgoing strong for nearly 18yrs in my car though i did have drop it and take apart a couple years ago for debris cleanout after aftermarket torque converter blew it's thrust bearing...IF you don't want to try another 700r4,there is th350/400 3 speed autos or th 2004r 4 speed auto-used in many '81-90 GM cars including '89 turbo TA and buick GN-if you use this tranny,you will have to mount the torque arm to the crossmember.2004r has better 1-2 ratio spread than 700r4.Then there are manual trannys...

 

A properly built 700r4 should take plenty more power than what your 305 can put out.
I would say either the rebuild wasn't right or the tv cable was adjusted improperly.
You should also add a external cooler for hard use.

Something like this would last along time behind a healthy 350, let alone your 305
https://www.700r4l60e.com/store/prod...&cat=20&page=1

 

I answered some of your questions in the first post with an edit. So please look to that for more info please.

 

If what you say in the first post is true than something was missed in the rebuild. I had a 700r4 for a few years behind a worked over 305 (216 hp to the wheels). It never gave me any issues. The one thing i will say is these transmissions run VERY HOT. I put a trans temp gauge in the pan just to see how hot it was getting and it would get up to 215 or so degrees and not come down again. I installed an aftermarket B&M transmission cooler and the temp never got above 195.

 

That would make sense that they missed something. And the trans couldn't have been too hot when it happened because the car had been running for ten minutes.