i searched and didn't find what i was looking for.

my friend has a 400 small block that's going into his newly acquired '86 trans am. the question is, will the 168 tooth flexplate clear the 700's bellhousing?
hmmm now that i think about it the torque converter probably wouldn't bolt up to the 400 flexplate anyways. is he stuck with using a balance-plate?
someone has to have done this swap, any ideas?

 

The 14" flex plate will fit.

The starter may not; may interfere with the exhaust. Most exhausts are OK but I can't see your friend's well enough to tell right now, it's too dark out.

If it's a "real" 400 flex plate with the 6 holes all on the large bolt circle, which I seriously doubt, then it won't work. But if it's a "350/400" one with 3 holes on the 400 circle and 3 on the 350 circle, like nearly all of the ones that have been used since the 400 was introduced in 1970, then it will, with possibly some minor hole filing being the only effort required.

 

all the auto trans bellhousings fit both diameters of plates


why would htey not ?

i think you are confusing manual trans bellhousings in which came in different sizes,
unlike auto ones

autos are all large housing, one size

good luck

 

thanks. i knew the 400 flywheel wouldn't clear the manual bellhousing, so it just raised a few fitment questions with me and my buddy. it's a lil' bit easier to get answers now before the tranny's on the jack!

 

In the past I have mated a 400 with an aftermarket flexplate to a 1986 TH700-R4. The flexplate was just your average thicker-than-normal 168 tooth 400 flexplate that can be purchased from any performance parts supplier. So I can comfortably say that a 1986 700-R4 and a 400 SBC will be happy together, well at least ignoring the fact that a stock 1986 700-R4 can't handle a descent 400.

As mentioned, the stock starter didn't work with any of the cheaper headers I tried. I don't know if some of the more expensive brands would have had better luck. I ended up modifying the passenger side header to clear the stock starter. Using a mini-starter would have been a better choice, but sometimes you just have to make what you have work.

 

yeah the car has a set of edlebrock headers on it now, and he plans on running a mini starter.

 

I use a stock 400 starter on my 406 with SLPs and it fits fine. I used the same setup with edelbrock headers and it fit fine as well.

 

mine did ok with hedmans too.