I am getting ready to rebuild my HEI distributor. Is it better to retain the stock weights and use lighter springs or should I buy a complete curve kit, like something from Moroso or Mr Gasket with the lighter weights?
Unless you have a machine, get it re curved at a shop that has a distributor machine.
I have not found any aftermarket weights that work without major grinding all over.
It's hard to get the timing to advance quick enough, the tip of the advance weight is too long, the weight too light.
I posted the following a few days ago in a different forum on this exact subject.
I've been reading through the posts on timing and have decided to go with IgnitionMans advice. I've just installed a Crane adjustable vacuum advance on the HEI I have on my 350. I connected it to full manifold vacuum on the 600cfm Edelbrock. I adjusted the limiter so that I end up with about 22 degrees at idle.
The HEI was on the car when I bought it and it appears to have an aftermarket mechanical advance weight set in it. I previously installed a MSD module. I've set my initial timing to 12deg with the vacuum advance plugged. Next I changed the springs on the mechanical advance to a blue and gold to start advance at 800 and have it all in by 2600. I then had my son help me by running the engine up to different rpms so I could "map" the mechanical advance. I could only get an additional 8 degrees of advance out of the mechanical. The flat spot on the weights didn't allow the mechanical advance to move any further. Sooo, I took the trusty Dremel to them. It took a couple of trial and error "grindings" and "mappings" to get what I was after. Ultimately I ended up having to take a good bit of metal off the unweighted side to get it to full advance - here's a picture. http://users.ev1.net/~martyp/69Camaro/DCP02150.jpg
Just took the car out and I'm amazed at the difference! The car is very responsive and it takes half the pedal for normal street driving. I suspect that this will also translate into better mileage. At full throttle, it rockets! Both me and my 14yr old son have the biggest grins on our faces right now...just had to share a success. This board rocks...thanks IgnitionMan.
looking at the pic I believe that the center pivot is flipped over the wrong way and that is why you could only get 8 deg of advance.
The pointed parts that were ground down go into the slots that are on the other side of the pivot (in the picture).
I did the same exact thing and couldnt figure out what the heck was going on until i looked at a picture in a recent Chevy High Preformance magazine and realized the mistake.
I got the proform HEI tune up kit
i use the silver weights and now the curve is exatly what i need
Eg, you sure about that? I tired placing the center piece in the other way, but it didn't seem to fit. I've got another set of weights that I may try that with tommorrow just for the sake of completeness. At any rate, the beast is running strong just now. I just installed a roll-stop tonight and can't wait to get it to the track.
running strong is the important thing
your center pivot is flipped according to the picture in the mag
i had it the same way you do now and then flipped it (to match the mag pic) and it fixed my prob
but it looks like the custom setup that you have now works good for you
my set up is slightly different as my timing is all in by 2800 and i run a higher initial
so it appears that the setup that you have now is right on the money (and if it aint broke dont fix it) lol
I hate to throw a spanner in the works, but
according to the instullation instructions
for mr Gaskets hei advance curve kit #929
camaro 69 ss has his weights & centre plate
in the correct way round.
I am no expert,and with my experiance with
the quality of some of mr Gaskets products
I would not beleive them if they told me
that the Earth was not flat,but they might be
I just thought this might help or maybe not.
I went back the the Mr. Gasket kit packaging and the way that I have it installed is correct according to this for a clockwise distributor. I have seen both the center piece and the weights turned both ways and opposite of what is in my pic. Could this be for a non-HEI distributor? Are there small block chevy distributors that are counter-clock-wise?
it was a Pertronix HEI distrubutor
the weights were in the same position but the center plate was flipped
the distributor produced 24 deg of advance in this config 12 initial 36 total
if Mr. gasket reccomend it the other way, i would go that way
perhaps different manufacturers have the weights and plates set up different
i just assumed that all HEI,s were set up the same way
sorry if i cause any confusion....
I have noticed that sometimes you have to look out for magazine articles. Sometimes when they are making the magazine they put a negative of the picture backwards and everything looks like you are seeing it from the other side
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