Beater 2316, CR versus deck height
Posted: Sat May 02, 2020 4:22 pm
Also posted on 914world, but, I think there are more type 4 engine builders here.....
So, finally getting around to building a "beater" engine to develop my race car project (been idle too long). The idea is to build a reliable, decent engine that's not crazy expensive to sort out my car, then put in the expensive engine when the chassis is ready. I will only use race fuel with this engine.
Basic specs are:
96mm JE pistons
AA Biral cylinders
80mm crank, chevy journals
5.4" Chevy rods
2.0L heads (Hoffman prepped) 51.3 cc
168/86B cam
So, to get ~0.040" deck height, I'll need 0.210" barrels shims (checked this today), but that puts me at a calculated CR of 10.7:1
Now, the question... should I source 0.220" or larger shims to drop the CR at the expense of deck height? A shim of 0.220" will drop the CR to ~10.4:1, but raises the deck height to 0.050"
Thoughts?
So, finally getting around to building a "beater" engine to develop my race car project (been idle too long). The idea is to build a reliable, decent engine that's not crazy expensive to sort out my car, then put in the expensive engine when the chassis is ready. I will only use race fuel with this engine.
Basic specs are:
96mm JE pistons
AA Biral cylinders
80mm crank, chevy journals
5.4" Chevy rods
2.0L heads (Hoffman prepped) 51.3 cc
168/86B cam
So, to get ~0.040" deck height, I'll need 0.210" barrels shims (checked this today), but that puts me at a calculated CR of 10.7:1
Now, the question... should I source 0.220" or larger shims to drop the CR at the expense of deck height? A shim of 0.220" will drop the CR to ~10.4:1, but raises the deck height to 0.050"
Thoughts?