shadowsniper3006 Posted December 23, 2006 Report Share Posted December 23, 2006 (edited) hey guys, I'm looking at putting a set of heads and a cam in my truck, the heads I'm looking at right now are 59 cc chambers and based off what i found with a stock gm gasket that will me at 11.1-11.2 compression. Does any one have any concerns with that high of ratio on 93 octane with 10% ethanol??? Also, i know this is only static compression and dynamic is the one you can play with a little via cam. I don't understand how to figure out dynamic ratio thou. can any one explain that to me?? I was thinking of using the xr275hr cam: 275,277 advertised, 222,[email protected] and .566,.568 lift on a 112. Thanks much and please offer all opinions on compression and cams Brad Edited December 23, 2006 by shadowsniper3006 (see edit history) Quote Link to comment Share on other sites More sharing options...
SuperSport Posted December 23, 2006 Report Share Posted December 23, 2006 (edited) hey guys,I'm looking at putting a set of heads and a cam in my truck, the heads I'm looking at right now are 59 cc chambers and based off what i found with a stock gm gasket that will me at 11.1-11.2 compression. Does any one have any concerns with that high of ratio on 93 octane with 10% ethanol??? Also, i know this is only static compression and dynamic is the one you can play with a little via cam. I don't understand how to figure out dynamic ratio thou. can any one explain that to me?? I was thinking of using the xr275hr cam: 275,277 advertised, 222,[email protected] and .566,.568 lift on a 112. Thanks much and please offer all opinions on compression and cams Brad <{POST_SNAPBACK}> Brad, From the specs you gave, I think you should be ok. There is a few more things you will have to know in order to figure it out. If you do a search over at ls1tech.com, you should find a ton of posts about this. A couple guys also give links or attachments for SCR/DCR calculators that you can use. I got mine from there Edited December 23, 2006 by SuperSport (see edit history) Quote Link to comment Share on other sites More sharing options...
06VHO Posted December 23, 2006 Report Share Posted December 23, 2006 Brad, here is some information for you. Also there is a DCR Calculator you can download. Click here. Quote Link to comment Share on other sites More sharing options...
shadowsniper3006 Posted December 24, 2006 Author Report Share Posted December 24, 2006 (edited) i tried doing some searching and found some answers but not sure if they are for the lq9. I found: bore: 4.00" stroke: 3.622 i think the piston to deck clearance is .025? what is our rod legth? 6.096? what is the head gasket bore? 4.04? What is the head gasket thickness for a lq9 gm gasket. .052 compressed? Thanks guys for any help! This my first go around on figuring this out. Brad Edited December 24, 2006 by shadowsniper3006 (see edit history) Quote Link to comment Share on other sites More sharing options...
shadowsniper3006 Posted December 24, 2006 Author Report Share Posted December 24, 2006 if the numbers i used are right. the 59cc heads would give me a 8.51 dcr. Is that where the motor should be or should it be higher to get more bottom end and a hp,tq curve that is lower in the rpms Brad Quote Link to comment Share on other sites More sharing options...
haulin79 Posted January 8, 2007 Report Share Posted January 8, 2007 You should consult with the cam manufacturer about the expected static vs dynamic compression ratios. I know that the good cam manufacturers optimize their cams for use with specific static compression ratios and engine uses. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.