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Ive got a new Distributor, and I want to make sure everything is in its proper place before I install it, Ive been led down so many roads trying to solve issues in the past, I know it sounds weird, but I just want to make sure its all good, Ive removed #1 spark plug, and stuck my finger in the hole. and cranked the engine til I got the blast of air. I can see the piston at the top of the cylinder.
With the exiting distributor cap removed (HEI if that matters), The rotor is pointed approximately right at the #1 sparkplug wire terminal. Ive marked a spot on the intake manifold where the rotor is pointing, also.
On the timing tab, see attached pic, Ive highlighted the timing mark. I know the finger in the cylinder method is just approximate, but what I don't know is which mark I will eventually try and time the engine to, once I install the new distributor. Ive read so much stuff on this site, my head spins. To make it more complicated, Ive got a 1977 Olds 350 installed in a 1972 Olds Cutlass. I think when I read my Chilton's, it'll tell me two different things.
Any pointers to get me right? My 350 is pretty stock, rv cam, Edelbrock intake / 600 carb (may be too small?), cast iron exhaust manifolds, 350 trans, and I think that's all the important stuff....
what I don't know is which mark I will eventually try and time the engine to, once I install the new distributor.
If you have a factory style GM HEI distributor, it will need somewhere between 14-20º initial advance. So I suggest you start with 14º as that is the highest your timing tab shows.
Here's a tip to help set the timing without getting a dial back timing light:
Rotate the engine so the timing mark on the balancer is at 0º on the timing tab.
Make a paint line on the balancer at the 10º mark.
You can now use this +10º mark when you are setting the timing.
For example, using the timing light set the new line to 8º on the timing tab and the initial timing is 18º (8º on tab + 10º for new line on balancer).
As for stabbing the distributor and getting the engine to fire, setting the initial to any positive value on the timing tab should be sufficient for the engine to run. Then set the timing to the desired number using the method above or a dial back timing light.
Last edited by Fun71; August 12th, 2018 at 10:27 AM.
Ok, I finally got to this project over the past weekend. I threw out the old GM HEI, because I always have been suspect there was something wrong with it. I purchased an MSD ready to run HEI distributor with a blaster 2 coil. I'm convinced that the Ignition system should not be cheaped out on, so I went the extra mile the quality of parts.
I think the little plastic bushings where the advance weights sit on the pins, just underneath the springs, were faulty, and throwing off my old distributor.
Because after installing the MSD stuff, The engine runs like I have never seen it already.
I have got the idle and the air fuel mixture pretty close, and as far as timing goes, I have got that timing mark at 14 degrees (like suggested above), with the distributor vacuum advance line plugged.
Tomorrow I will go out and make the 10 degree mark on the balancer, so I can set the timing as suggested....
Also, does anyone think the carb being 600 cfm is a problem?
Last edited by Gone Johnson; August 29th, 2018 at 10:00 PM.
Timing at 10-12 degrees seems best, and 600 cfm carb chokes and starves during full acceleration, then recovers immediately after let up. Thank you very much. Carb is not spec size, so I will start there.
On the ready to run distributor it coms with the blue stop bushing installed for 21* 0f mechanical advance. Add your 10-12* your at 30-32 total. If your still running this bushing I'd bump it up 2 more, it should like it. Connect your vacuum adv to manifold vacuum and you should be good to go.
Okay this is a new one. I'm eager to try. The Machine Shop guy who sold me my Distributor told me to install the lightweight spring, AND the medium weight spring, I'm not sure if this is what you are saying. I will grab the box, manual, and parts kit tomorrow, and look?
Okay this is a new one. I'm eager to try. The Machine Shop guy who sold me my Distributor told me to install the lightweight spring, AND the medium weight spring, I'm not sure if this is what you are saying. I will grab the box, manual, and parts kit tomorrow, and look?
Using both medium springs would bring the advance in faster than stock. Two light springs will bring advance in faster than the medium springs and possibly cause detonation. I think by using one medium and one light spring could be a compromise. Try what he suggests. If you get detonation, try changing a light spring with a medium spring.
If you look at your instructions figure 4 picture E, second one from the bottom right, 1 silver light and one blue light spring. It brings your 21* of mechanical advance using the blue advance stop bushing in at 2500 rpm. I usually like to use figure D which brings it all in at 2800 rpm using 2 blue springs.
Instructions https://www.jegs.com/InstallationIns...1/121-8529.pdf
August 11th, 2018, 07:09 PM
