on a high compression motor, is the timming set higher or lower than stock? my motor calls for 6 degrees btc. i have bumped the compression up so i think the timming should be diff. (higher or lower) ...frank...
timing Hi. if the motor knocks or pigs on accelleration then advance the timing a couple of degrees until it stops knocking or pinging If the engine keeps running after you shut off then back off timing just a touch. this works for me. keep a record of the results at each setting for future refrence.
timing Higher compression motors require higher octane fuel not regular. low octane fuel will cause a knock also or cause the engine to keep running after key is turned off. cya at Round-up
Are you sure about that? I thought it was the opposite. I've always advanced the timing until the engine knocks then back off in one degree increments until the pinging stops. F.Y.I. - advanced timing moves the torque curve Down the rpm scale, (better driveability). Conversely, retarding the timing will move the peak torque UP the rpm scale. Well, at least that's what I've been told (I'm easily fooled). edited: I could NOT get back on here to edit it earlier. I shoud've put "drunken post alert" or sumpin on the original post. Thanks, TL.
Well, you're all a litttle off. First of all, backing it off until you don't "hear" the pinging is not adequate, as detonation or pre-ignition can still be occuring even though you're not hearing it. It's really bad when you can hear it. 2: Advancing the timing moves the torque curve down in the RPM range, giving you better low-end throttle response or off-the-line power. Retarding it does the opposite. Same goes for camshaft timing. Retarded cams are for high RPM operation. 3. At higher altitudes, you want to advance the timing by 2-4 degrees. Stock calls for 6 degrees and I actually run 12-14 initial, and 38 total. My engine is not high compression though. 4. Use a timing light to adjust timing, not your "ears". Detonation, also known as pre-ignition ("pinging") hammers your pistons and makes the engine run hotter. The newer cars have "knock sensors", because you cannot hear when an engine is starting to detonate. You don't want to run less than the 6 degrees initial spec., even with high compression. You should be able to run 6 to 10 with no problem, provided you are using fuel with the proper octane rating, as suggested by others in this thread...
let me see if i am reading this right. one said up...one said down... and one said up or down is off...o.k....thank you very much...frank...
36 to 38 degrees of total advance (not counting the vacuum advance if you have it) is best for economy and power. You can sometimes realize more power in the higher RPM ranges by retarding the timing at the upper ranges. There are circle trackers and drag racers that use "locked" timing - an ignition system that has no advance mechanism and the initial advance is set at 38 degrees. This works well for an engine that idles above 2000 RPM but for a street machine you are better off with a fast working mechanical advance and a tuned vacuum advance. PaulS
I am running my timing 13 degrees advanced initial and total 36 degrees. My compression ratio is 10.5:1 Dan
I love it! My timing is locked out at 36 all the time ...so I know even if sometimes I`m retarded my car sure is`nt!
