I was looking at your site to see what your combo ended up to be.I see that peak HP on a 350HO is rated at 5000. Does it seem to want to pull much past 5000? or does the power start to fall off. I noticed you used a 8" harmonic balancer, were you abil to re-use your old 305 flex plate?
Thanks
Dave

 

I get a creepy feeling of Deja-Vu.....

 

well i have the engine he has in my car and i have to say it pulls very good past 5000 rpm i shift aroud 5500, the 305 flex plate will work too.

 

Ummm is your 350 engine internally or externally balanced?
My 350 was internally balanced and I could NOT use the 305 flexplate.

 

Page 4 out of 9 in the 350 HO Engine Specifications (12486041) INSTALLATION INSTRUCTIONS;
Top of page titles: Flywheel / Flexplate:
"Due to revisions in the crankshaft design, a 350 HO engine must have a counterweighted flywheel (or flexplate) for proper balance." Some part numbers for flexplates that work, 14088765, 12554824, 14088761, and the one that came on my L03.
A little piece of information from my Small block CHEVY PERFORMANCE volume two: 1982 and Later;
BTW, the book is from SA (that's a good thing).
page 38, top of page shows the 2 different flexplates. "Late model cranks with the one-piece rear seal have a smaller 3.00 inch diameter crank flange bolt pattern that requires the appropriate flywheel or automatic transmission flexplate. The flexplate on the right (PN10128412, one with the weight) has a noticeably smaller bolt pattern compared to the early piece on the left (PN 471529). These are both small diameter 153-tooth flexplates."
In other words, awesome question. I probably should have made it clear on my website to use the weighted flexplate but it's the only one that fits unless you get a custom aftermarket version.