If im doing it right yeah. Bushing on. I revved it up until i seen the mark stop moving, held it and dialed back the timing light to keep the balancer mark at zero. Dial read 45* ?? I swore I had the vacuum adv disconnected while checking total, I KNOW I did when getting the initial. I AM turning 40 this weekend... Maybe the stress is causing some **dohhh** moments with my memory already. I'll try it again later today and confirm. Could be a bad timing light? It is an older one. Sent from my LG-H811 using Tapatalk
Post the distributor part number. It's on the circumference of the distributor right below the cap parting line.
I can mail you a free bushing if you need one. I made a few out of copper tubing. Sent from my iPhone using Tapatalk
Hey thanks Matt! I'll run this timing again with and without this mr gasket bushing and see what it does. I may need one Sent from my LG-H811 using Tapatalk
Oops, I didn't read everything and didn't see that you have one. Well, if your mr. Gasket bearing goes rolling across the garage floor, I can send you a replacement. Good luck! Larry helped me last year and this spring with distributor advance issues. Sent from my iPhone using Tapatalk
Ahh gotcha, yep i have one. thought you were saying you had different sized ones. I'll keep you in mind when this one vanishes after hiting the floor like everything else does. Sent from my LG-H811 using Tapatalk
Larry, my distributor has 1111474 stamped on it. Not a stock 68 I guess. The only thing I found was on Georges site, a reference saying its a 69 GS350 dizzy? And to confirm yes the 45 total i was getting is WITH the limit bushing installec and vacuum adv disconnected. Initial @11 Sent from my LG-H811 using Tapatalk
I had similar issues. Someone had installed a distributor from a 350 on my 455 (put a new gear on it to fit on a 455) with WAY TOO MUCH mechanical advance, even with a bushing. I ended up buying a rebuilt points distributor; Larry found one on eBay for me. It was perfect. I actually love points and the old schoolness of them as the HEI doesn't get you more horsepower. My goal is to keep making this car faster and keep the points. Now I'm at around 12 initial and 32 total mechanical. The rebuilt points distributor was under $100 easily. If you don't want to spend the money, you could always weld the slot; bring it in 1/8" or so. Larry would know best on the distance. I just didn't want to fiddle around with that part as I was getting impatient. Question: is the sweet spot of 30-34 true for small blocks as well? Sent from my iPhone using Tapatalk
I don't have that number distributor in my sources. 45* total is too much. 30-34 is what you need for an iron headed 350 or 455.
Ok thanks guys. I will attempt to weld the slot when i get a chance. In the mean time I've bumped the timing down to 8* to help the total come down a bit. Cant really drop much lower or i doesn't like it at idle. vacuum adv limited to 8* Maybe I'll keep an eye out for a decent priced rebuilt. Sent from my LG-H811 using Tapatalk
I like the 1112109 distributors. They have somewhere between 12 and 16* of mechanical advance, so you can run a lot of initial timing, which a bigger cam loves. Here is one on E Bay. looks unmolested. http://www.ebay.com/itm/1968-1972-G...ash=item33ba84d888:g:CwcAAOSw8RJXBzdx&vxp=mtr
That looks like a good deal. But wouldnt it be too low of a total for me if my initial is where it is now? I've noticed it doesnt like to be advanced more than about 14* initial or it will have a noticeable miss or sputter at idle and just off idle. You can hear it in the exhaust and feel it in the motor if I advance it past that. It seems to like between 10-14*. Should I be able to advance more than that? Maybe something else is going on? Sent from my LG-H811 using Tapatalk
That's strange, it should not miss, after all, it will go above that from the mechanical advance. It does not miss then does it? Maybe search for a distributor with 20* in it. That would be ideal.
Not that i can tell. It will miss at idle and cruise. Can feel the sputters. Runs good just with misses. But jumping on the throttle i dont notice it at all. Thats why i brought it back a few degrees. Seems to really like it between 10-14. Idles nice and no miss Sent from my LG-H811 using Tapatalk
You have something else going on there. If you are running 45*, the vacuum advance will put you into the 50's and it may surge up there especially if the carb is a bit lean.
Is setting the timing all in by 2500 rpm's by using light springs and modified vacuum advance recommended for a stock motor? I will be installing a Petronix 2 ignition and have installed new plug wires, cap and rotor. Engine is a 1973 J code 350 4bbl in a Century with turbo hydramatic 350 with 25k original miles. I will also be installing a dual exhaust to replace factory type single exhaust. Removed air pump and blocked passage to manifold. All components otherwise stock. Runs very well, only issue being a slight stumble off idle which is much improved since running carb cleaner directly into idle passages and advancing initial timing. I seem to recall, having driven these cars "back in the day" that they had a hesitation off idle from day one due to lean emissions settings. Thanks.
Yes, any car can benefit from a quicker mechanical advance. Keep in mind that you should also limit the vacuum advance if you plan to do this. The stock slow mechanical advance was only partially in at cruise RPM, and the vacuum advance would supplement that for a cruise timing of around 40*. Now you have all your mechanical advance in at cruise and the vacuum advance can put you over the top. That can cause surging. Set your total advance to what you want. The initial will end up where it needs to be depending on the total you set and the amount of mechanical advance in whatever distributor you currently have installed. Odds are it is a different distributor in a 43 year old car. After you use the lightest springs to set the total, put heavier springs in to bring it in later. 2500 is a good target, it doesn't need to be exact. With an all stock engine, the light springs can have it in too early, and that can cause idle irregularities.
Thanks Larry. Your original post said to limit total advance to 30-36 degrees by limiting vacuum advance. I checked my distributor, and the # is 1112109. Could be original as this car had two previous owners and 25,000 original on the clock?
No, that's not what it says. For some reason, lots of guys get confused about vacuum advance. To function, vacuum advance needs engine vacuum. At wide open throttle, engine vacuum is at or near zero. The vacuum advance canister has a spring inside that OPPOSES the vacuum applied to it. In order for the vacuum advance to change timing, engine vacuum has to overcome the spring tension. When you go to wide open throttle, engine vacuum goes to 0, and whatever advance from the canister was there, goes way, because the spring in the canister pulls it out. When I say total advance, I mean the initial advance + the mechanical advance, because that is the ignition timing with the engine at wide open throttle. The distributors fitted to different year Buick engines differed in the amount of mechanical advance built into them. You can not change the amount of mechanical advance in a stock distributor without disassembly and welding, so you are stuck with what you have. Vacuum advance is in addition to the initial + mechanical, and it is there because an engine will get better fuel economy at light load cruising with more spark advance than it could tolerate at wide open. Now everything I have written above is in that very first post. I find the biggest problem is that some have no basic knowledge about what actually goes on inside of a distributor. Without that basic knowledge, you won't understand why you are doing what is described in this thread. A good place to find the basics is right in the Buick Chassis Manual for your year. If you do not have a copy, you should get one. They are not hard to find on E bay. Here is a screaming deal, http://www.ebay.com/itm/1973-BUICK-...ash=item41b0237afa:g:ig0AAOSwHoFXqNDv&vxp=mtr The 1112109 distributor was also used in the 1972 350 engines. It only has 12-16* of mechanical advance. That means when you set the total wide open throttle advance to say 32*, the initial advance will end up somewhere between 16* and 20* The only problem you might have is hard cranking when the engine is up to operating temperature. The engine will like it though. It will have more power.
