TheSamba.com :: View topic

Thu Oct 23, 2008 2:03 pm

Alright, I'll start this off with a yes i did use the search feature and i'm not having much luck finding what I need.

I was cruising through the forums last week and saw an engine displacement table and now i need it.

as it turns out the 69mm crank i ordered is in fact a 74mm, it was boxed wrong and I'm going to use it.

anyways, does anyone have this table avasilble?

Thu Oct 23, 2008 2:42 pm

http://www.cbperformance.com/enginecalc.html

I've done 4 motors now with 74 cranks. They are nice to work with as depending on the case there are no clearance issues with stock rods. I did have to shave off a little on 2 of them though. 7x.85.5 gives u a 1699 (1700) and a 74x87 gives a 1760. Both are nice mild strokers, and no more difficult to build than a stock motor really.

Thu Oct 23, 2008 2:47 pm

He will either need cylinder shims, or pistons for the 74mm crank.

Thu Oct 23, 2008 3:03 pm

thank you very much you guys...

alright, now...

I've never built a motor with a stroked crank in it before.
as i understand it, using the 85.5mm pistons that i have already, along with the stock connecting rods, i need to shim the cylinders out 2.5mm on either side, is that right?

which leads to the next question, what about push rod length?

Thu Oct 23, 2008 10:03 pm

2.5mm longer? when i put new heads on, I had to space the rocker arms out a bit in order to get enough adjustment out of the adjuster screws, so you might be fine and dandy with doing nothing, HOWEVER, I wouldnt bank on it, there are a ton of places online that make custom length pushrods, usually to accommodate higher ratio rockers.