If I put a 153 tooth flexplate on my sbc how much difference will it make in how it starts? It will want to spin the engine faster so assume crank over harder. Is it noticeable and is it hard on the starter? I'm guessing 9% which is the difference from 168 to 153.
I need to do this to get my headers to clear the starter.

In my experience, it will be fine. I have done the same with some packages.

I am a firm believer in the 139 tooth starter / Flexplate deal. MUCH stronger and lasts longer. It does spin motor over a little faster but no big deal. The main thing is there is less teeth and they are bigger so they just do not break off a tooth.

When I first went to injection 4 th or 5th time I started it with brand new flexpalte it kicked back and broke some teeth off the fleaxcplate. So I had to pull it all out and replace a brand new flexplate. Went to 139 tooth and have not had single problem since. I think that was 2012?

Normally we do not see a big difference in RPM. The larger 168 does give the starter more leverage so it does help some.
The 168 will also give you more oil pan clearance.

The 139 tooth flexplate is the same diameter as the 168 tooth.

Thanks for the replies.

I dug my spare mini out and it has the ability to remove the mounting block and flip it over. The solenoid is now on the bottom which offsets the motor to the inside instead of the outside. I now have 1/4" clearance with the starter in the outer set of holes so I'm goo to go.

quote:

Originally posted by 1leg:
Normally we do not see a big difference in RPM. The larger 168 does give the starter more leverage so it does help some.
The 168 will also give you more oil pan clearance.

The 139 tooth flexplate is the same diameter as the 168 tooth.

Yes, the 139 and 168 tooth diameter is the same but I think the starter gear for the 139 tooth is larger diameter.

on Meziere starters the pinion gear is the same diameter. The tooth count is different. The 168 tooth starter has 11 teeth and teh 139 tooth starter has 9 teeth.

quote:

Originally posted by 1leg:
on Meziere starters the pinion gear is the same diameter. The tooth count is different. The 168 tooth starter has 11 teeth and teh 139 tooth starter has 9 teeth.

Great info thanks for posting.