How many different size bell housings came on TH350's. I am being informed now that the one for a 168 tooth flex plate and the one for the 153 tooth plate are different and the one for the 168 tooth plate will not fit in the tranny tunnel of my 82 z28. I have a 168 tooth plate on my 385 I just built.

Where do I measure the bell housing at to determine the size of my bell housing.

If I have to clearance the tunnel, what all is involved? Just beating it to fit or what.

Thanks ALL.

 

Only differences I know of is that theres a Chevy bolt pattern, and B-O-P bolt pattern. They all used 168 tooth flexplates far as I know. And it fits fine in the trans tunnel, lots of guys use the TH350 in these cars. I've seen it in a few local cars too. Only issue some have mentioned is the trans dipstick tube clearing the firewall - theres a solution, but I dont know what it is myself.

 

Actually there's 3 different bolt patterns. Chev, BOP and a combination of both.

They should all work with the larger 168 tooth flexplate. The TH350, TH400 and 700R4 all use the same flexplate/torque converter setup so all the bellhousings will fit under the tranny tunnel. How tight is determined by the rest of the tranny and the TH350 is smaller than the 700R4 so it's an easy swap.

An expensive solution to a tight fitting dipstick is using a flexible one from Lokar.

 

Awsome, thanks guys. So, The tranny will fit with the exception of the dipstick tube maybe. I have also heard from a few guys on here that if I use the 168 tooth flex plate then I should use the 98 chevy truck starter since it is a mini, has a staggered bolt pattern (my block has both), and will clear the bell housing and exhaust. Thanks the motor and tranny build is almost ready to get installed.

 

I don't know if a starter from a 98 will fit onto the older blocks but if it does, use it. It will save a lot of weight and give more room.

The TH350 swap will need a different or modified crossmember. The TH350 tranny mount sits about 2" farther ahead than the 700R4. If you use a long tailshaft TH350 (9"), you can reuse the driveshaft. If you use the shorter 6" tailshaft TH350, you need a driveshaft from a third gen that cam with the 200c 3 speed.

You need a manifold vacuum source for the modulator valve.

 

It should be the same... '98 still would have used a Gen 1 block (5.0 or 5.7 Vortec IIRC)