OK, sounds pretty ideal. As long as it isn't pinging, and the plugs look good, and the car isn't surging at steady state high way speed, you're good to go. 34* might be safer for iron heads and pump gas. Look at the spark plugs. Sometimes you may not hear the beginnings of detonation, but you will see it on the plugs. Looks like little purple specs on the porcelain. http://i102.photobucket.com/albums/m92/m007_01/detonation2.jpg~original
Ok, I will keep an eye on the plugs. If I wanted it down to 34, just add the bushing? And should I limit the vac. Adv. To 10 or 8,
No, simply reduce your initial timing to 12*. As long as the engine isn't surging, leave the vacuum advance as is.
Recommended: Initial: 12-14*, Mechanical: 30-36*, Vacuum: +14-18* 30-36* WOT, 38-44* with vacuum. I have: * Initial: 14 * Mechanical: 20 * Vacuum: +16 34 WOT and 50 with vacuum. 14* = hot-starts ok, starts to hesitate at 15*. I haven’t street tested yet, but should I lower the vacuum to +10 = 44* with vacuum? Or should I lower the initial also? (430,850cfm quad,msd dist+super conduct wires, NGK UR-5, slow city cruiser and redlight racer)
As long as it doesn't surge on the highway or under light throttle, you can leave the vacuum advance the way it is.
I just read on a Pontiac forum that 12* initial would give more power than 15* initial. Is he wrong, or is it just Pontiac, or have I misunderstood and 12*+22* is better than 14*+20*?
He is wrong. The total timing is important for WOT power. There is no hard fast rule for how much timing an individual engine wants. In general, Buick V8 engines do best with 30-34* at WOT. Initial timing is important for idle and cool running. Moderate to big cams like lots of initial timing for best idle and vacuum. There are no short cuts here. You need to experiment with your engine. The best WOT timing will produce the highest trap speed at the track. Too much timing will damage the engine.
I have a '72 Skylark 350-4 bone stock car that's had a dual exsaust system installed that runs very good. I tuned it up, new points, condenser and plugs. I also timed it as per factory sticker on the motor. I'm planing on doing power timing next. My question is is there anything I should know about for this year car when power timing it or just follow the instructions given? I have removed all air conditioning components and installed an air conditioning delete cover so now I have lots of room to work. Thanks, Brad
Are you sure? That part number looks like a Pontiac distributor for a 250 CID 6 cylinder. http://www.yoyopart.com/oem/14260279/gm-1110378.html The factory distributor for the 1972 Buick 350 is 1112109, so yours has been changed. The question is, to what? I can't find that part number in my Buick literature.
Wow! how strange, I'm attaching a photo so you can see the numbers. if it is the wrong distributor would my best option be replace it? the car runs really good. maybe it'll run better with the right distributor?
No, I just don't have any specifications on it. If it is installed in a Buick 350 and runs well, use it. I don't know how much mechanical advance it has because I can't look it up. What you can do is put some very light springs in it and see what your total advance is. As long as it is in the 30-34*, that is good. If not, adjust it to that. Then put the heaviest springs you have in, lower the idle down as low as it will go and check what the initial timing is. Subtract the initial timing from the total timing, and that will give you how much mechanical advance is in that distributor. Remember to disconnect the vacuum advance before you do this.
Thanks Larry For your expertise, I just checked Ebay and someone has the correct distriburtor for sale. I may pick it up just in case. Once again thank you, Brad One more thing the sticker says I have to have the the car in drive with the vacuum lines plugged to time it and set the dwell. that's how I timed it the last time I did it. I don't feel that the safest way if I need to increase the rpm's of the motor. Can I do this with the car in park?
The only reason they tell you that is to make sure the RPM is low enough so that there is no mechanical or vacuum advance when you set the initial timing. That applies anytime you want to set initial timing, you want to make sure the weights are fully retracted, and no vacuum is applied to the canister. BTW, that sticker is completely useless. Even with the right 1112109 distributor, it was completely useless. It told you to set the initial timing to 4* with a distributor that had a maximum of 12-16* of mechanical advance. Do the math, at WOT, you'd have 16-20* of total advance. That alone will hamstring any Buick 350. I have no idea why Buick would do that other than emissions considerations. We have no idea what you have in there now. If you set your initial timing to 4*, what will the total timing be? We don't know. That is why I am advising you to set the total advance. The initial will then be what it must be. Setting the initial advance without checking mechanical and vacuum advance is short sighted and can potentially cost you power, or damage the engine. The whole purpose of this thread is to show how to go beyond that and get the best power/mileage/efficiency. Yes, set the timing with the engine in Park.
My 72 350 runs best at 36° total ,checked it last night it has 18° initial ,18° mechanical with vac disconnect. Is 18° initial A good number .