Distributors and advance in a 350

[Guest E.Murray]

I have a pretty mild 350 in my 260Z (bored .030, Performer intake, that's about it). I'm looking at upgrading the ignition system in preparation for bigger things down the road. Right now, I'm thinking MSD 6AL and new coil, but in my looking around I've considered a new distributor as well. The debate is HEI (and if so, stock vs. MSD or Accel or something) or non-HEI. Right now I have points and was going to use the Pertronix to get rid of the points and condenser, but for not a whole lot more than the $110 Ignitor, I can upgrade the dizzy... Anyway, my question is twofold:

1. I've done a lot of searching the archives and can't come up with any kind of consensus on distributor. Leave it, Ignitor, HEI, MSD...? I have a little money to spend, and am looking for good reliable performance.

2. My bigger question is advance. I'd like to keep the vaccuum advance (which you can't do with some MSD units). What kind of timing are people with similar engines running? Not just at idle, but in terms of amount of vaccum and mechanical if I end up going adjustable. The possibilities are dizzy-ing (no pun intended) when you consider that all 3 are adjustable. How do I get the best performance out of a fancier distributor? Test methods (short of dyno time)?

Any enlightenment you guys can offer is appreciated.

[jack46]

Many have told me an HEI is as good or better than many aftermarket dizzy's. They say if you simply put a better coil in the HEI it will go to lets say 6500 (conservative number I think) that is far beyond what you will pull with stock motor so why change more than the coil?

 

I'm not against changing it, but if it isn't going to make a noticeable difference, I ask why do it? I would suggest you plan where you want to go, and buy what gets you there. A piece here and there will in the long run cost more and perform poorer.

 

A decent change could be a cam (Summit has combos ie cam and lifters for like $80 Sum-K1102/3 might work well with performer intake or maybe even bigger to 1105) if you go beyond stock then you will prolly need a stall converter to match the cam (can often find one for ~150 used and get ~2500 stall effective which means the convertor is prolly rated at 3200 or 3500). Or they have stalls for ~150 for smaller cams.

 

It is combination and to simply put in a bigger cam with low compression won't help either. You need to decide how far you want to go, larger and faster is nice, but costly. Will you drive it daily, and simply want alittle more or can gas mileage take a dump etc.

 

Trust me I was same way I didn't think it through and have tried MANY different parts! And BTW once you do get faster then the mod's to make it stay togehter get expensive as well.

[jack46]

From the little I understand of timing there are three values: initial, vacuum, and mechanical. I'm told SBC like a total of 36 degrees as a ballpark number. If you set initial to 8 advance this leaves you 28 for dizz. If your dizz is set for a max of 28 degrees then no matter what that is all it can advance be it x from vacuum and y from mechanical (centrifical) the two are limited to the total for the dizz which in our example is 28. To verify total advance you can buy timing mark tape for the size harmonic balancer you have then rev engine to about 3000 rpm and see what the total advance of your system is. All timing is supposed to be in by 3000 rpm so no need to rev much past that just verify that the dizz is not adding more. I hope this works it is how I checked mine so should be ok (verified it with a set back light that a friend lent me)

[Guest E.Murray]

36 and 8. Those are some of the numbers I was looking for. Thanks.

I notice you're from Tullahoma, TN. That's really weird, because that's where this car lived up until 3 weeks ago. It's a red 260 with no rear bumper... Small world.

[jack46]

That is strange. Write me at

slow260z@yahoo.com