MSD Mechanical Advance issues

[dyeager535]

I thought you set advance with vacuum disconnected? So under heavy throttle the most he'd see is 30* as it's setup now, right? Under certain cruise conditions he might see 46*, but that might be fine for that driving condition.

At idle he'd have 24* if hooked to manifold vacuum, should idle good.

 

[Philly87]

Right you are dyeager535. Set the mechanical advance timing with vacuum advance disconnected. At wide open throttle vacuum falls off therefore taking the vacuum advance out of the picture and running the motor on mechanical advance alone.

Chris,

Glad this finally worked out for you. Again my aplogies for the initial headache.

-Phil

 

[Fordum]

Just a suggestion, why not send the old weights and springs back to Phil? Its not of any importance now what was wrong, since its fixed, but it might be nice to see what the original problem was.

Who knows there might be someone else out there with the same problem, and MSD might see something about the parts that would let them tell a customer what to look for.

Its a personal quirk, but I like to know..........

 

[CGT80]

Just a suggestion, why not send the old weights and springs back to Phil? Its not of any importance now what was wrong, since its fixed, but it might be nice to see what the original problem was.

Who knows there might be someone else out there with the same problem, and MSD might see something about the parts that would let them tell a customer what to look for.

Its a personal quirk, but I like to know..........

I thought about that. I don't know if it would be worth it to them, but I am still curious as about how I ended up so far off when I bought the parts, that msd specified, from summit. It seems to me that the problem is either with the weights or springs. I'm no expert, but now I am really fast at pulling out an HEI dizzy and reinstalling it

PS. Right now I am running ported vacuum to the vac advance as smog calls for. I have run it both ways in the past. Once I am done with smog, I will bump my initial back to 12 degrees. I might go back to manifold vac and see if it helps acceleration at all, since my curve is much slower than what I had. It won't respond as fast now, but I haven't driven it since the last changes. I had to set my vacuum advance to cut out about 7 inches of vacuum. This engine still pulls 5 inches at WOT.

 

[CGT80]

My truck passed smog with some tweaking to the fuel mixture. The first run was just over max emissions. The next run was below average. The truck still gets a bit warm in city traffic with the ac on-up to 215 degrees, but it runs just fine when it is warm. I can get on the gas and it just pulls like a mule, even at over 200 degrees. It used to loose a lot of performance over 180 degrees. This was all with 8 initial, 30 total, and 46 with the vac advance. I am going to bump the initial back to 12.

I took almost all of my tools out of the boxes, so the truck probably only weight 5400 lbs now. I nailed it up a freeway on ramp the other day. I was going up hill. I chirped the 33x12.50 tires when it went into 2nd gear at 4500rpm. It does have a hard shift 1st to 2nd. 2nd to third isn't quite as hard. The trans has all kinds of goodies in it.

The next test will be to tow my toy hauler with it. The trailer weighs around 9k pounds. It may be a while before I get to use it again though. Also, I might throw my q jet back on the truck to see if it helps build more power, since the edelbrock performer is small for that engine.