I recently purchased a Mr. Gasket advance curve kit. Some of you on here say to swap and mix and match springs to get your advance to come in at the right time. I have a very knowledgable buddy who says that you should stick with 2 of the same springs. IE, 2 light springs, 2 heavy springs, 2 med. springs. He says if you start to mix and match springs with eachother it causes the centrifical weights to bind. Is this true? Can I mix and match springs?

Zach

 

No that is not true.

IIRC with that kit, the usual setup that works best is the weights that come in the kit, with one light and one medium spring.

Next time you want one of those kits, get the Crane one instead, with the adjustable vac advance can. Much better bang for the buck.

 

You can get the adjustable advance peice seperately.

 

True of course....

But if you buy them together, you basically get one or the other for free. Free is good. Paying extra is not.

Hence, the comment about "bang for the buck".

 

FWIW, I'll have to say I have nothing good to say about that Mr. Gasket advance kit. I've purchased 3 over the years, and not one of them worked right.

Go with a different brand.

BTW, what are you putting this in? Your sig doesn't indicate a non-computerized application.

 

Absolutely, but incase he is kicking himself, he can get the other one later.

Five7kid, i picked one up recently as well, a guy with over stock was selling them off for $5 (no adjustable advance), and they were packaged new, so i figure what the hell, i need one anyway.

Are the springs and weights just not engineered right or what? Or prone to breaking, or.....?

 

Not engineered properly. Mainly the curvature of the weights and cam.

 

That's actually a fairly big deal, in general, with stock distributors....

The little cam that sits on top of the shaft, that the "tail" of the weights work against to put the advance into effect, varies WIDELY from one dist to another. Which is one of the many reasons why it DOES make a difference what stock dist you start out with, as the core for building one up. The shape of that cam determines the rate at which the advance occurs. If you think about what the springs and weights are doing, you can figure out that at some RPM they just barely begin to fly out, and at some higher RPM they fly all the way out; but, depending on the relationship of the weight "tails" shape to the shape of the cam, the advance might occur for example very rapidly over the lower portion of that RPM range and then only slowly over the higher RPM part, or smoothly all the way through the band, or all up at thie ghigh end, or whatever. It makes a HUGE difference for street driveability and gas mileage tuning. You can put the same curve kit into 2 different distributors and come up with COMPLETELY different results; especially if the car's cruising RPM is somewhere within that RPM range. The actual ignition timing you end up with can be substantially different at the RPM the motor spends its time at, depending on the dist core you used; even if the static timing is the same and the "total" timing is the same (the 2 "ends" of the range). And it's not at all easy to tell what you've got, other than by spinning the dist up and seeing what it does.

There used to be some one of those cams tha twe would look for; but it's been 20 years or more since I did any of that. I don't recall what one it was, any more.

 

It's going in my 91 Formula. I have a 650 DP carb and a points style distributor w/ the electronic conversion w/ rev limiter.

 

Ah, you weren't specific.

The old standby Delco points distributor used different weights & all than HEI, so make sure you have the right kit.

I haven't had trouble with those kits.

And mixing springs for the proper advance curve is exactly what you do with them.

 

I could never get the curve right with the Mr Gasket kit.

I went ahead and bought the crane kit. heaviest springs for a 800-3200 curve, and stock dizzy weights. 16* initial, 20 mechanical, and vacuum locked out at 15*, works like a charm.

 

Thanks for the replies guys.

 

Got a part number for crane's HEI kit?

 

http://store.summitracing.com/partde...1&autoview=sku