If you were doing a 103 kit would you go with a 3.875 bore for 1691cc or 3.885 for 1700cc?

 

Bigger is always better!!

Steve

 

That's what I was thinking no replacement for displacement!

 

What's the cost difference? 9ccs on 1691 is what.... 1/2%? If it's a big cost difference to get the bigger bore, I'd put that money toward porting or a good dyno tune.

 

3.875 bore x 4.375 stroke= 103.2 Cubic Inches x potential 1.2 hp/tq per cubic inch = 123.8hp/tq
3.885 bore x 4.375 stroke = 103.7 Cubic Inches x potential 1.2 hp/tq per cubic inch = 124.5hp/tq
3.950 bore x 4.375 stroke = 107.2 Cubic Inches x potential 1.2 hp/tq per cubic inch = 128.7hp/tq

Not enough to be able to tell a difference between the first two, and from the 103 to the 107, 4 cubic inches at a best of 1.2hp/tq per cubic inch, apotential of an extra 5hp and tq.

This is potential with absolutely everything being near perfect, most will never realize numbers near to those, but it gives you an idea of what the differences are.

 

Well I was going to just do the 103, and since the bore price would be a one time cost no matter how much you have to take off and the piston kits are all the same price I might as well go with the 3.885. I'll have to research the 107 a little more because the cam states good for a 96 or 110 with flattops and can be used in a 103 with dished pistons so I'd have to look at what I could do with a 107 and how it would work.