Distributor question

[turnpike boy]

At present I use a straight-mechanical advance distributor (MSD) on my little motor (331"). This was done primarily to avoid detonation issues - better timing control - and because the motor runs right around 10.4:1 compression. I have been thinking lately, however, that the benefits of a vacuum-advance unit (like better mileage) might be a better choice - but have some concerns about that hi-vacuum, part-throttle condition and the potential effects on detonation that the extra 10* or so of timing might give rise to that.

So - can anybody give me some good advise/realtime experience with vacuum advance dizzy's with moderately hi compression ratios and normal, every-day gasoline that's available these days?


-Roger

[RICK LAKE]

Roger the MSD 8680 will do what you want except that there is no vacuum signal to the controller box. It is a manual knob you mount under the dash. Adjust it to different settings depending on what you are doing. A boost retard box that is used for supercharged cars might work. They have a sensor that adjust the timing and retards. It depends on the boost signal. Best bet is call tech line and see what they say. Most retard and advance timing is either the weights in the distributor or software controlled. Hope this info helps Roger. Rick L. Ps how my job opening coming?Everything is frozen in NJ

[turnpike boy]

The only thing about the 8680 is that it will require my constant and unending attention to settings - turn it up in steady-state cruise, and turn it down when going for power.

No, the 8479 is the piece I think is needed....but I still would like to know how it will make out in controlling preignition when under full-tilt vacuum conditions.

The job....well, I'm lining you up, Ricky, for either our next Executive Director (big boss at NJTPA) or for the new Governor of New Jersey. That second one might make you think I don't like you, but be assured that is NOT the case - I just wanna assure myself that we both make it to retirement without having to eat dog food as a staple in our diets.

-Roger

[RICK LAKE]

Turnpike boy Roger We was in town on sunday from2-4 pm. The town hall meeting was a blood letting. I got my 2 questions to ask, 1 on no rebate money for solar systems, 07 was cleaned out in april of 07 and the 08 money was gone Jan 3 of 08 for this year. He is also looking for an advisor board members for oversite on watching the money. NO PAY. This will be another A$$ kissing group of his friends. I give him credit, He stood up there for over 2 hours and was beaten to death. He is a tough guy. He does know about the big problem and picture. We are all going to eat a piece of that $H!t sandwich and it's going to hurt. What wonderful advisors the govenors have had and the damage they have done to NJ. Rick L. Ps I may have to move to PAI want to get the car on the street. Know anyone who's address I could use???? It is easier to car the car done in PA than NJ now. Pss I will take either job. I know the differents between right and wrong and white and black. I do have a small grey area. with LIMITS. Rick It's time to put the USA back to work and get out of sand box.

[rooster]

I thought it was a distibutor question. What's with the politics?

[turnpike boy]

Just two old reprobates, taking the time to break each other's b*lls. Nuthin personal.

OK - back on topic.

Ain't there nobody out there got experience with vac advance on these motors? And can answer a question about timing sensitivity?

[vector1]

i thought the vac advance helped with streetability. under part throttle you have advance, mash the pedal and the timing retards to avoid detonation, especially on hiway. hurts performance though. maybe i'm wrong.

[RICK LAKE]

Turnpikeboy Roger What you really need is a knock sensor with a timing controller. To retard the timing when the motor starts knocking. The problem is if you are running solid lifters and have a little too much lash, the sensor will pick this up and retard until it stops. Problem is it willn't stop. you can retard to 20 degrees. There was or is a company that has something for timing. I will Google it and see if it comes up. Sorry to anyone else about the quick politics. It was an inside joke between Roger and me. Rick L.

[RICK LAKE]

turnpikeboy Roger, what you are looking for is sold by J&S Electronics in Cali. number is 714-534-6975. You want the safe guard marine setup. This is good for any weather, like if you get caught in the rain. You need a trigger for the crank. It has a vacuum port to monitor for what the engine is doing. Says it works with MSD. Call Tech and ask? The other thing is if your motor has solid lifters or gear drive cam kit, this sensor will pick up the noise. Rick L.

[turnpike boy]

Ricky, you da man!

I guess I should have been more clearer in my request for info, but you saw right thru it, magician that you are.

That was my concern; I'm not too afraid of using vac advance, but very hesitant to do so since I've got a better chance of becoming a nun than I do of hearing some detonation.....would only be able to check on this after a toot and looking at plugs. But by then, much of the damage is done.

The motor has hydraulics and chain drive so this should work. Thanks, Rick, I will call them today and git the lowdown.

[jwd]

There is NO reason NOT to run a vacuum advance on the street. Your engine will run cooler, have better throttle response and you'll get better gas mileage. It needs to be hooked up to constant vacuum. Get a vacuum unit that is rated at 2" vacuum less than what your engine idle vacuum is. You don't have to worry about detonation as your timing retards when any load is put on the engine. Mechanical advance only distributors on the street is another one of those "if it's good on the track, it must be good on the street" ideas that is completely wrong.

[RICK LAKE]

Turnpikeboy Now that we are on the way to fixing your problem, can we get back to busting B@!!s and polotics Hope it helps Roger. That knock sensor should pickup the sounds. If you get it make sure of the correct location to mount the sensor, Some times they are in the heads and sometimes in the blocks. IMO blocks are better. Not sure about the ones in the water drain holes. You know you might want to look at your A/F ratio. The LM-1 is good for this also. Running too lean can cause a pinging problem. It's the cruise mode when driving and everything leans out. IF you want to get crazy, and EGT would also help. This is more for supercharged motors. Good Luck. Rick L. Brain fart, I little water injection with a good kit will stop the whole problem, but that is more under WOT not cruise. Got your popcorn, Now back to the govenor job:L OL: