I alway's am interested in what combinations will create what compression ratio's and what I need to get a certain compression yadayada so I made a compression calculator in MS Excel to do just that. It takes engine parameters and calculates a number of vital engine parameters to help make head, head gasket, piston, rod, crank selections much easier when building your custom engine. This not only works on LSx motors. I've tried this on all my 4cyl Honda engines as well and it is dead on accurate so download it and give it a try. I'm hoping that it will help out alot of people to build motors and select the right parts. Shops can use this as well to set up motors instead of going through a page of math to select engine components.

 

Very cool. A guy on CF did a spreadsheet that calcs dynamic compression based on your cam specs. It would be double-cool to combine these two together.

 

where is the dynamic compression chart ^^^ that would be cool-

Thanks

 

well if you could link me to his I could def add in some other formula's to get the dynamic compression too. I just don't have the formulas to add them in.

 

https://ls1tech.com/forums/advanced-engineering-tech/394937-updated-valve-event-dcr-scr-header-length-spreadsheet.html

 

http://forums.corvetteforum.com/show....php?t=2167025

 

Nice find

 

Here is an updated version of my calculator from above. It now has Dynamic Compression calculation as well. Just input your info/spec's in the yellow shaded cell's and it will spit out the numbers. Lot's of time spent on calculating volumes so it's pretty close to exact. Even takes into account the larger bore of the head gasket that most motors have.

 

thanks for this one.
i already have a couple of calculators, but this one take into acct other elements, as you mentioned earlier, the gasket used.

i just need to find Piston Comp. Height and Block Deck Height to complete my calculations for my ls3 418 and setup. thanks!

 

can someone explain why when i punch the stock LS2 specs i'm coming up with 11.07:1 instead of the 10.9:1 that GM advertises? here are the figures i'm using.

bore: 4.000
Stroke: 3.622
Rod Length: 6.098
Piston COmp Height: 1.338
Pisoton Dome CC: 0.00
Head comb CC: 64.45
head gasket: .053
Block Deck: 9.240
Cylinders:8
Head Gasket Bore: 4.020

what am i screwing up?

 

I don't think that "you " are the problem . . .

Try running those numbers through THIS calculator.

http://www.diamondracing.net/tools/

I believe the "EXCEL Calculator" has an error in it, somewhere.

 

http://www.wallaceracing.com/Calculators.htm