Spitfire Posted July 11, 2006 Report Share Posted July 11, 2006 My 'shee came with a 7* timing key (Vito's), and I was just wondering if advancing the timing this much would require other's mod's, like race gas or something. My head is already shaved .0020". Thanks! Quote Link to comment Share on other sites More sharing options...
dajogejr Posted July 11, 2006 Report Share Posted July 11, 2006 What is your compression at? Quote Link to comment Share on other sites More sharing options...
Spitfire Posted July 11, 2006 Author Report Share Posted July 11, 2006 What is your compression at? Not sure, I'd have to check. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted July 11, 2006 Report Share Posted July 11, 2006 Compression has less to do with race gas need than timing, or at least when you're talking 4 to 7 degrees more of it. Get a compression reading, and...what elevation are you at as well? Quote Link to comment Share on other sites More sharing options...
Spitfire Posted July 11, 2006 Author Report Share Posted July 11, 2006 Well I know that with the shaved head, I need to run 93, race gas is unneccessary. I'm at 500ft above sea level. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted July 11, 2006 Report Share Posted July 11, 2006 If you don't know what your compression is...you don't know if you need to run race gas or not. Every motor is different. Once you start to get into the 150 plus PSI range...a mix of race/pump may or may not be needed. However, add 7 degrees of timing, and it is. 155 to 165 with 7 degrees...and you're gonna need more octane yet. I would say for safety's sake, test the compression. Don't take someone's word for it on the 93 pump gas on the .020 head....test it. I'd say with .020 to .030 off, plus all that timing, I'd be surprised if you didn't need at least a 50/50 mix or so. Check the compression, better safe than sorry.... Quote Link to comment Share on other sites More sharing options...
ssanddemon Posted July 11, 2006 Report Share Posted July 11, 2006 (edited) Something I have not seen mentioned yet is that degree keys suck. I have had one shear, and a buddy's did as well (and these were 4* keys). Best to ditch that key and do it right with a plate. Oh, and check the compression! P.S. Fegot to mention, I am running 7* with 160 psi compression at sea level. Runs OK with no pings on super (91) but responds really well to a 50/50 of 110. Edited July 11, 2006 by ssanddemon Quote Link to comment Share on other sites More sharing options...
Spitfire Posted July 11, 2006 Author Report Share Posted July 11, 2006 Something I have not seen mentioned yet is that degree keys suck. I have had one shear, and a buddy's did as well (and these were 4* keys). Best to ditch that key and do it right with a plate. Oh, and check the compression! P.S. Fegot to mention, I am running 7* with 160 psi compression at sea level. Runs OK with no pings on super (91) but responds really well to a 50/50 of 110. Yeah, I may just get rid of the key. I'll check my compression tommorow though, it runs great on 93, no pinging at all. 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.