Engine timing?????

[WetSpot]

What kind of timing do you guys run, base and total? I have a comp cam and they recomend a base timing of 18 *. I think I have 12* biult in the distributor......

[H20MOFO]

Thats a pretty conservative setting(30* total). I've been asking total timing questions on this board befor it went down..over on performance boats ...everywhere I could. The best answer I can give you is that there are a lot of different variables that will effect your timing. Altitude, open chamber heads vs closed, cam profile, fuel type, compression, ect . Personally I think 30* is a little too conservative, but too conservative never blew up a motor. Others may or may not agree with me but I'd bump it up a couple of degrees at a time while gps'ing until you hear detonation or no longer see mph gains, and then come back down a couple.

[shaun]

On my deal i was told 36*, and if i wanted to try to get away with it to run 38*. I stuck with 36* since i'm pushing the limits of pump gas.

[WetSpot]

Today I just got in the mail a positive piston stop from Jegs so I can check and see if my timing tab is reading correctly. It is....:rolleyes: I also got a timing tape for the balancer. I had to get the tape because I "lost" my roll back timing light. So my question is, I have points and oval 049 heads with a Speed Demon 850 Annular carb and Basset thru-transom headers. What do you think total timing should be?

[H20MOFO]

I don't know that any one could answer that for sure. Whats you compression ratio? how much overlap in your cam? altitude? pump gas or? I think you'd be safe starting around 33*. And if you don't hear any detonation, or see signs of it on your plugs(silver molten metal specs) then try another degree or 2, until you no longer see gps gains, or hear the dreaded ping.

[WetSpot]

Comp Ratio - 10.0 to 1
Sea level
Pump Gas
Cam specs.......http://www.compcams.com/Cam_Specs/CamDetails.aspx?csid=410&sb=1
:idea: :) :( :D

[H20MOFO]

I dunno, prolly same answer but start at 32*. Where is it set now, and how does she run??

[WetSpot]

I had ot set at 38 last year when I first dropped the new motor in. Ran great! 5700 rpm. Then I found out that that might be alittle too much timing for a jet (first jet). So I backed it off to 32. Ran good but could never get my 5700 rmps back. I could only spin 5100. Not to mention it ran real rich all throughout the rpm range. I hear of guys running up to 36-38*. Just wondering if 38* or maybe 36* would be pushing it. I never heard any pinging at 38*, but then again I have open Basset headers. Never new enough at the time to check the spark plugs. :idea:

[H20MOFO]

I'd still say slowly take it up a degree or so at a time, and watch gps and tach results. Someone else please chime in if I'm wrong, but the one time I pinged a motor I had absolutly no problem hearing it (with ot bassetts). I had a lean motor, too much timing , and an octaine issue, and yes it was fugly.

[jtmarten]

What kind of timing do you guys run, base and total? I have a comp cam and they recomend a base timing of 18 *. I think I have 12* biult in the distributor......
Did a machine shop tell you 12* in the dizzy? If not, it's really cheap insurance to know for sure, I paid $50 for a local shop to set up the advance for marine use, and determine the total advance in the dizzy.
You have to double the dizzy #, so you have 24* total in the dizzy, which means you wouldn't want to go over 12* base timing.