pistons?

Injected1

Member
Re: pistons?

These look like the same pistons I am running (TRW-L2441) with cometics and vortec heads. If you want my opinion go with a flat top to put your compression in the 9.0-9.5 range these pistons will be close to 8.0:1. It gives you more punch out of the hole w/o the turbo spooled and you don't have to run the boost so high which means less heat. I am sure someone can do the math but in generic terms a truck with 8.0cr needs to run 22lbs of boost to make 400hp where as truck with 9.5:1 needs only 16lbs to make the same hp. Boost is fine but it's the heat that is not so good for making safe hp, cooler air is denser and combusts better.

PS this should be in Engine Tech.
 

BMFB

Not to scale
Re: pistons?

http://www.csgnetwork.com/compcalc.html

according to this, with a standard rod and crank, .030, .040 gasket thickness, i should be at around 8.5:1 i think. but im not sure about the deck clearance they're like a -20.3cc piston, where like the srp's that everyone uses are a -24cc, so i thought it would be a bit higher than stock, around 8.5.

i also learned today people have a different concept of what the value of the cc rating should mean for pistons, which confused me at first, what i mean to say is some people say that a ( - ) in front of is lowering your CR and some say its gaining. summit says ( - ) is a gain in CR as its taking away from the cc of the head as in 64cc - say 14 is 50CC, so its now a higher compression, and some say 64cc - 14 comes to 78 CC, so lowering CC, just thought id share.

also im sorry i miss posted this, I wasn't sure it was gonna turn into a tech thing, but i dont think i can move it.
 

Synister

New member
Re: pistons?

I believe most compression calculators have you add positive number to determine your dynamic and static compression ratios with a recessed piston and a - for a dome or protrusion type crown design. The catalogs are listing there is an overall - XXcc recess

PM sent
 
Top