No Limit Powersports Posted June 24, 2004 Report Share Posted June 24, 2004 I was thinking of playing with my timing a little since I ditched the key and bought the adj plate. What do you guys think would be the best. Right now I have mild port & polish noss head 19cc domes vforce reeds 340 mains stock pilots lightened flywheel cpi inframes. Iam running pump gas at about 1000 ft not sure what my compression is right now. The timing is at +5 right now can I go to +7 safely or will I not notice a difference gimme your opinions. Quote Link to comment Share on other sites More sharing options...
sredish Posted June 24, 2004 Report Share Posted June 24, 2004 Now, I'm not saying it's good or bad, but I've heard of 'em being ran up to +12, but I'm not sure how much difference there is between +5 and +7 or +7 and +12, but I know some run it there. In fact, a bud runs his at +10 or something, but I'm unsure how much better it will run. Someone else here can tell us, I'm sure. Maybe I need to bump mine up some. Quote Link to comment Share on other sites More sharing options...
dlnoss Posted June 25, 2004 Report Share Posted June 25, 2004 This is off topic but: You may be pushing the limits of pump gas with the 19cc domes and stock timing but with it advanced, I would definitely be afraid of pump gas. Your porting could change that but probably not a minor port. What is your compression. Quote Link to comment Share on other sites More sharing options...
sredish Posted June 25, 2004 Report Share Posted June 25, 2004 Hey Mr. Noss, would I see any benefits from upping my timing from +4 to, oohhh say, +7 or something? Don't know and don't want to risk detonation. Scott Quote Link to comment Share on other sites More sharing options...
dlnoss Posted June 25, 2004 Report Share Posted June 25, 2004 Scott, There are others here more qualified to answer that. I've heard a lot of differing opinions but know that advancing does increase temps and tendency to detonate. -David Quote Link to comment Share on other sites More sharing options...
No Limit Powersports Posted June 25, 2004 Author Report Share Posted June 25, 2004 I need to check my compression to be sure I havent had any problems with overheating yet. I was running 20cc untill I got my port job and they told me I could go down to a 19cc. If I up it to +7 is the temp going up the only way to tell if Im detonating or is there a good way to read the plug for detonation. Does anybody know what the pros and cons of more advance/retard are. Quote Link to comment Share on other sites More sharing options...
PlaynSand Posted June 25, 2004 Report Share Posted June 25, 2004 I think Banchetta did some dyno testing on this subject ,you might do search . I left my timing stock , just to play it safe . I hate melted pistons. Quote Link to comment Share on other sites More sharing options...
dlnoss Posted June 25, 2004 Report Share Posted June 25, 2004 This is just my opinion but, until you know for sure, I'd at least mix some race gas in. By the time detonation shows up on a plug the damage will probably already be done. Plugs are a lot harder and melt at a lot higher temperature than a piston. If you trash it because of detonation you could be looking at a complete teardown to clean up the mess. I'm probably cautious but I run 110 with 19cc at 800'-1400' elevation and my timing isn't advanced. Quote Link to comment Share on other sites More sharing options...
No Limit Powersports Posted June 25, 2004 Author Report Share Posted June 25, 2004 what do you guys recommend as safe compression for pump gas or at least 93 octane after I do the check. Quote Link to comment Share on other sites More sharing options...
jrm312 Posted June 25, 2004 Report Share Posted June 25, 2004 i wouldnt run over 150 to 160 psi would be pushing it a little close. i run pump gas with 22 domes on a noss head with 93 oct at 151 psi with stock crank, so i would check you compression and determine what kind of gas to run, my guess is that your way over 160 and you should run 50/50 mixrace and 93 oct. just my 2 cents 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.