Hey guys I was crunching some numbers figuring out my dynamic compression with a calculator I found around here. I punched all my specs in and this is what it gave me:

Static CR: 9.03:1

Dynamic CR: 6.58

Cam specs: int/exh ADV 283/284

233/235 @.050

.619/.621 lift

114* ICL

116* LSA

Does this 6.58 seem right?? When I search around I see others in the 7.0+ range and this number doesn't reflect boost or attitude. But I'll be the first to admit I'm no professional in this area. Anybody with a better knowledge wanna chime in?? I'd appreciate some more pro advice on this. Thanks a lot guys

 

Motor is iron 370" forged crank, wiseco dished -11cc pistons, 6.125 rods, new LSA heads no milling, will also have BW 75/96 turbo 1.32 ar. Looking to throw 16 psi at it. My elevation is 1300 ft

 

Post your cam card, need your intake valve closing point ABDC?

 

It's 51*

 

That's @ .050". Usually DCR is calculated using advertised numbers, usually @ .006".

 

I made a few assumptions to get the static CR to 9.03 -- basically I assumed a 370 with 72cc heads, a 4.160 x 0.054 head gasket, and the 11cc dish.

And that puts your DCR right at 6.58 using the 0.006 valve lift event as KCS described (using the 283 advertised duration to get the 0.006" IVC. If you're concerned about it, you'd want to mill the heads or move to flatter pistons to improve compression

 

Awesome thanks guys. I just wanted to make sure I was crunching the numbers right. And it appears I was going the right way

 

Just as an FYI, I ordered some summit Pro LS Forged pistons at the beginning of December and I still dont have them. ETA keep getting moved back, as of now they say 3/18/2022. Just find out if they have them in stock before ordering!

 

This thread, which is approaching 4 years old, was about dynamic compression calculation. No discussion on ordering anything.

 

thought i was posting in a different thread. No idea how it got in here. sorry about that.