tranny help on 70' mav

with a 170 1 6 i was going to drop a built 302 in it but i need to knoe if my tranny will bolt up and hold the power i was told it was a c4 but now i'm not sure any help would be GREAT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! please im or call (951)-282-8485 and ask for AJ thanks alot

 

The transmission will not bolt up, and will not take the power if the transmission is stock.

 

ok now i know it wont bolt up so what tranny will bolt up with no mods and hold to the power of a stock 302

 

A c-4 from a 250 i6 Maverick will bolt up, but it'll need to be rebuilt to handle more power. I wouldn't worry about the no mods deal; if you're buying a used transmission 99% of the time you'll want to rebuild it anyway.

 

I believe if you have a c-4 now you can use it if you change the bellhousing. Also remember that if you do change the tranny make sure you get the right convertor for it. After 1970 they went to a 26 spline input shaft. Here is a good site for the c4 tranny.
http://www.mustangcentral.net/tech/c4.html

 

The C4 behind a 170 has three clutches in the direct clutch pack and four in the forward pack. If you want to use your transmission you will need to get the 250 I6 or 302 C4 clutch drums that hold one more in each clutch. You will need a V8 bellhousing, flex plate and converter to match your new engine. You can probably find a decent C4 from a v8 or 250 I6 to use as is in the local wrecking yard or want ads. A C4 core is worth about $50 around here so don't pay more than you should for one that is working. If you want to add some performance to the new or rebuilt C4 install a TransGo 40-2 valve body kit (it is easy even for the novice).

 

So are you saying that the C4 tranny behind a 170 6 cyl engine doesn't have big enough clutch drums......AND that they are a different drum than what is used in a C4 behind a 250 or a 302?

Thanks

 

The drums are the same externally but the groove for the retaining snap ring is lower. There are ways to cut a new groove that allows more clutches but if you don't have a lathe and the tooling to cut the groove then it is cheaper to buy used drums or a full core.

 

Thanks Paul.

 

its pretty simple rebuild also, something that you can possibly do in your own garage

 

so 250 c4's were built to the same spec as the 302 c4 but its the 170-200 c4's that were "weaker"?

 

The 170's, 200's, Pinto's and Bobcat C4s all used fewer clutches. The Pinto used two clutches in the direct pack and had to be up-dated to three to prevent "harsh engagement" into third.