Distributor installation problem

[homeslice]

I have had a new L31 crate Engine installed for about a year. I just did the 411 PCM swap and got a black bear tune. When checking camshaft offset retard I was at -26°. I was able to get it to -4° before the distributor ran in to the intake. Yesterday I decided to redo The distributor install, and the best I could get was either -4° or 7°. I spent all day on This yesterday, what am I doing wrong? By the way it is a summit racing Vortec distributor.

 

[deadbeat]

Others may disagree, my dads truck had that distributor and I had the same problem. I ground the corners off the plastic where the clamp goes so I could turn it to dial it in to 0.

 

[454cid]

I have had a new L31 crate Engine installed for about a year. I just did the 411 PCM swap and got a black bear tune. When checking camshaft offset retard I was at -26°. I was able to get it to -4° before the distributor ran in to the intake. Yesterday I decided to redo The distributor install, and the best I could get was either -4° or 7°. I spent all day on This yesterday, what am I doing wrong? By the way it is a summit racing Vortec distributor.

I guess I'm not following... how is it that you can hit numbers on both sides of zero, but not zero itself? What is your procedure?

 

[homeslice]

I guess I'm not following... how is it that you can hit numbers on both sides of zero, but not zero itself? What is your procedure?

Great question. I have no idea. I used the Aloicious distributor install procedure. The closest I've ever been was the 1st time I installed the dizzy about a year ago. It ran at -26 degrees for a year, and I then fine tuned it to -4 just a few weeks ago. After I redid the dizzy install (yesterday), I started the truck and got -100 degrees, and was able to get that down to -18. Went thru the entire procedure for a 3rd time, and got positive 40 degrees. I was able to get that down to positive 7 degrees before running out of dizzy travel. I've never had anything mechanical eat my lunch like this has. Wish I still had the OE dizzy so I could run a trap check.

 

[454cid]

I used the Aloicious distributor install procedure.

The what?

Wish I still had the OE dizzy so I could run a trap check.

A what?

 

[homeslice]

The what?

This...http://www.gmtruckcentral.com/articles/distributor.html


A what?

Here is a link to the procedure I used..http://www.gmtruckcentral.com/articles/distributor.html

I'm saying I wish I still had the factory distributor so I could install it and verify if I could get it to zero offset once installed.

 

[east302]

Just to make sure...you are looking at the “CMP Retard” (or something like that) and not the actual ignition timing on the scanner, right?

Not sure if this is the one you used, but I got mine to around +0.2-degree or so.

https://www.summitracing.com/parts/sum-850098

At such a low number, you’re just barely bumping it to get it to zero and hoping that you don’t shift it when tightening down the hold down clamp. I think luck has a lot to do with it, but if you’ve gotten negative and positive numbers then hitting zero is certainly feasible in your case.

By the way, I’d ditch the cap that came with it and put on a Delco one. Mine started misfiring after a few months and I notice some of the other reviews say the same thing.


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[homeslice]

Others may disagree, my dads truck had that distributor and I had the same problem. I ground the corners off the plastic where the clamp goes so I could turn it to dial it in to 0.

Just to make sure...you are looking at the “CMP Retard” (or something like that) and not the actual ignition timing on the scanner, right?

Not sure if this is the one you used, but I got mine to around +0.2-degree or so.

https://www.summitracing.com/parts/sum-850098

At such a low number, you’re just barely bumping it to get it to zero and hoping that you don’t shift it when tightening down the hold down clamp. I think luck has a lot to do with it, but if you’ve gotten negative and positive numbers then hitting zero is certainly feasible in your case.

By the way, I’d ditch the cap that came with it and put on a Delco one. Mine started misfiring after a few months and I notice some of the other reviews say the same thing.


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Yes that is the same distributor, and yes I'm looking at CMP retard using an Autocal and EFILive. The Summit cap crapped out within 6months, and happened to my son as he was driving down the highway; the engine just died. I've had a delco cap on it for about 6 months.

I thought the same thing, that zero was surely attainable as I've registered positive and negative numbers on either side of 0, but no dice. I'm starting to think I have an incorrectly machined/indexed distributor. Or, it may just be a case of grinding the distributor to allow travel to 0 degrees offset as Deadbeat mentioned.

 

[east302]

Are you reusing the existing hold down clamp? I tossed the one that was attached to the Summit distributor since it allowed no adjustment.

Grinding the hold down area seems to be an option, you’d just think that you wouldn’t have to do that. The distributor being in such a crappy location doesn’t help things.


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[homeslice]

Are you reusing the existing hold down clamp? I tossed the one that was attached to the Summit distributor since it allowed no adjustment.

Grinding the hold down area seems to be an option, you’d just think that you wouldn’t have to do that. The distributor being in such a crappy location doesn’t help things.


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No, I'm using the OE clamp, so no problem with adjustability. My problem is that the distributor itself is running in to the intake before I can get to 0 degrees offset. I've had it run into the intake to the left and to the right (rotation of the dist). When I have to turn it to the left, I can get to -4 degrees. When I have to turn it right, I got it to -7 degrees. This is the best I have achieved, and I've gone thru the procedure 3 times. I bet I stabbed the dist into the engine 100 times. My knees are toast today from kneeling on top the radiator.