VIIISecondRide

I read the sticky about the swap, but while I was swapping my 1991 RS 305 TBI with a 1991 Chevy G2500 350 TBI I found the little gear reduction starter off the 305 would not mount on the 350 block. Was I looking at something wrong? I couldn't get the bolt holes to line up, and the starter wouldn't clear the flexplate. I had to use the big honkin' van starter.
Anyone else run into this?

Schurkey

OEM starters must be matched to the flywheel diameter. There are two possibilities: 168 tooth, and 153 tooth. The larger flywheel uses an angled (staggered, diagonal) bolt pattern, the smaller flywheel uses the straight-across bolt pattern. The two bolt patterns share the outer hole, but have different inner holes.

I have a 400 block that does not have the inner "straight across" bolt hole drilled 'n' tapped. Therefore very difficult to mount a small flywheel/straight across starter, and very difficult to mount a typical "mini-starter" which also has only the straight-across pattern.

First Guess: Your 305 uses the small flywheel, the 350 has the larger one.


Angled (staggered) pattern for 168-tooth flywheel:


Some mini-starters are double-drilled to space them properly for use with either size flywheel using the straight-across bolt pattern:

VIIISecondRide

Schurkey- That is something I never knew or encountered in the auto parts business. I assumed all smallblock starters were the same!
I have a different block, but kept the flexplate. The 305 starter had a short and a long bolt- the 350 starter used two long bolts. It catches the flexplate just fine, but I don't think I can get that big booger out of there without dropping the exhaust!
Thanks for the info!

Fast355

iTrader: (2)

You may have already finished this setup, but you can use a gear reduction mini starter for a 1997 Vortec Express with the larger 168 tooth flywheel. They will crank just about any small block you can build. 1.7 KW motor with a 5:1 gear reduction.

http://www.oreillyauto.com/site/c/de...eyword=starter