63 Fuelie stumbles off idle

[Dan D.]

Re: 63 Fuelie stumbles off idle

The OP was specifically talking about ignition. Head gasket will not enter the discussion. When I stated "adjacent cylinders in the head", I was pointing out the proximity to each other of the primary wires for each.

5 and 7 are the only pair of cylinders that are a threat to crossfire because:

1. They are adjacent in the firing order,

AND

2. They are also adjacent in the head, which means that their secondary wires are routed close to each other.

If both 5 and 7 wires are in good condition then this threat is minimized.

3 and 6 pose the same threat as any other consecutively firing pair, which is nil. 5 and 7 are the only pair in this unique situation.

Joe, I don't know why you are angry with me. The gentleman identified the problem as 3 & 6.

The consensus here is that he has a bad Pertronix unit and I agree.

But I want to be at peace with you, so I am bowing out of this discussion.

[Troy P.]

Re: 63 Fuelie stumbles off idle

Yes, easy to find the magnets since the don't travel far before sticking to something metal.

It looks like the magnets were just a press fit in the plastic ring; not glued in. Then there was a clear thin flexible plastic donut ring that covered the magnets and helped hold them in. Not sure how that was attached. Probably just sticky. In any case over time from engine heat, etc. that clear plastic comes unglued and falls away from the ring holding the magnets. That allows the magnets to eventually fall out.

I may call Pertronix and find out what changes, if any, they made to the Ignitor to solve that problem. As an engineer I'm curious. Nevertheless I'm going to install the Ignitor II model rather than the Ignitor.

[Jim L.]

Re: 63 Fuelie stumbles off idle

Troy, yours isn't the first Pertronix to toss its magnets and cause misleading problems. A '58 vintage racer I sometimes help on did this a few years ago. Symptom was a skip, of course. It took forever to find because obvious things like cleaning spark plug, changing plug wire, replacing distributor cap, even cleaning the FI nozzle didn't help. IMHO, the embedded magnet design is a poor one. Points represent an upgrade.

Jim

[Joe C.]

Re: 63 Fuelie stumbles off idle

Joe, I don't know why you are angry with me. The gentleman identified the problem as 3 & 6.

The consensus here is that he has a bad Pertronix unit and I agree.

But I want to be at peace with you, so I am bowing out of this discussion.

Dan,

I'm not angry with you, and am sorry that you feel that way. Please don't take offense.

The 5 & 7 possibility was mentioned before the OP ID'd 3 & 6 magnets missing from his pole piece. 5 and 7 crossfire was mentioned as a possible cause before the culprit was identified. Did not want anyone unfamiliar to misunderstand. 5/7 crossfire is only possible due to leaky wires because 2 conditions are present, and not present with any other pair on a Chevy V8. The cylinders must be adjacent in the firing order as well as being in physical proximity in the engine. 3/6 does not fall into this category.

[Joe C.]

Re: 63 Fuelie stumbles off idle

Yes, easy to find the magnets since the don't travel far before sticking to something metal.

It looks like the magnets were just a press fit in the plastic ring; not glued in. Then there was a clear thin flexible plastic donut ring that covered the magnets and helped hold them in. Not sure how that was attached. Probably just sticky. In any case over time from engine heat, etc. that clear plastic comes unglued and falls away from the ring holding the magnets. That allows the magnets to eventually fall out.

I may call Pertronix and find out what changes, if any, they made to the Ignitor to solve that problem. As an engineer I'm curious. Nevertheless I'm going to install the Ignitor II model rather than the Ignitor.

Troy,

The newer Pertronix II has the same construction of the pole piece. I don't like it! It also has about .010" runout, which I was unable to correct, so when setting the air gap, a bit of compromise is warranted. The Ignitor III uses a better design, although it is absolute overkill for your application.........it has a built in rev limiter.

In your case, as I stated in post # 34, you should use a Breakerless SE if you are not using your car for racing. The design is much more robust! I have an almost new one which I removed from my engine last year, that I'd sell if you are interested. The drawback for me, and the reason I removed it, is that the SE requires that you use the stock coil with ballast resistor. I needed a more powerful ignition system, and the Ignitor II produces up to 45 kv (if needed) and is compatible with the MSD 6AL ignition module.

[Troy P.]

Re: 63 Fuelie stumbles off idle

Don't know that one. Are people happy with it?

Although I have the Ignitor II on order from O'Reillys I was told I don't have to pick it up. If not they'll just send it back.

[Troy P.]

Re: 63 Fuelie stumbles off idle

John recommended that one as well. I'm interested for sure, Joe. I'm happy with the stock coil and ballast resistor for a driver car.

Please email me with details. troy.pyles@comcast.net Go easy on me is my birthday!

[Dan D.]

Re: 63 Fuelie stumbles off idle

Joe, I like being friends with you much better. All is forgotten. Now I am really going to bow out.

[Duke W.]

Re: 63 Fuelie stumbles off idle

IMHO, the embedded magnet design is a poor one. Points represent an upgrade.

Jim

I'm glad to see someone finally said it.

I don't recall a thread about points failing, but electronic points conversion problem threads occur once in a while even though probably no more than 20 percent of vintage Corvette engines have them.

There was a Corvette Restorer article last year about points including which set to install based on maximum engine revs and other factors.

Duke

[Joe C.]

Re: 63 Fuelie stumbles off idle

I'm glad to see someone finally said it.

I don't recall a thread about points failing, but electronic points conversion problem threads occur once in a while even though probably no more than 20 percent of vintage Corvette engines have them.

There was a Corvette Restorer article last year about points including which set to install based on maximum engine revs and other factors.

Duke

Predictable response.

If points were the be-all end-all solution, then automotive engines would still have them.

Pertronix has improved their ill-concieved design with the Pertronix III....................meanwhile, the Breakerless SE, which is ideal for mild duty such as is necessary for people here, is and always has been bulletproof.

I'll say it again: innovation and improvement did not end in 1970!

[Jim L.]

Re: 63 Fuelie stumbles off idle

If points were the be-all end-all solution, then automotive engines would still have them.

Just to be clear..... that's not what I said or implied.

Compared to the Pertonix design that uses magnets embedded in plastic (or whatever it is), points are a better, more reliable, proven alternative.

A well designed and thoroughly developed electronic ignition system is a fine idea. The key concepts, though are well designed and thoroughly developed . It's not at all obvious that those two traits apply to all (or even most) aftermarket ignition systems.

Jim

[Troy P.]

Re: 63 Fuelie stumbles off idle

I sent an email about the failure to Pertronix. I'll post whatever reply I get, if any.

[Joe C.]

Re: 63 Fuelie stumbles off idle

Just to be clear..... that's not what I said or implied.

Compared to the Pertonix design that uses magnets embedded in plastic (or whatever it is), points are a better, more reliable, proven alternative.

A well designed and thoroughly developed electronic ignition system is a fine idea. The key concepts, though are well designed and thoroughly developed . It's not at all obvious that those two traits apply to all (or even most) aftermarket ignition systems.

Jim

Jim,

The response was not directed at you, and I realize that that's not what you implied. Someone else here has a long history of touting the glory of points over and above electronic points conversion systems of any kind. Your target was Troy's particular pole piece design using embedded magnets. I agree with your observation and stated that fact. Someone else expanded upon what you said, to make a wholesale criticism of electronic points conversion systems, and mentioned having no recollection of "a thread about points failing". What does that sound like to you?

The Pertronix I and II pole piece should have a Mylar sheath covering the plastic housing with embedded magnets. The sheath serves to provide a continuous, ultra low friction surface in the event of contact between the pole piece and the pickup. The sheath also serves as a secondary means of containing the magnets, should they detach from the plastic housing. Not the most robust of designs, and there are two additional faults with it:

1. The plastic-with-Mylar sheath design is not always true in the vertical plane. I was unable to straighten it, and was unwilling to use heat to soften and recast the ring.

2. Thrust clearance of the distributor shaft must be monitored because as this increases, the vertical travel of the shaft will cause the air gap to increase over time.

Breakerless SE does not have either of these problems, employs a stamped steel Hall Effect pole piece, does not require removal of the main shaft for installation, and requires NO adjustment. It is fixed in position, and vertical tolerances are not an issue.

All of that being said, I prefer the failed system over points, although the 1996 version may or may not have included a Mylar sheath. Points degrade over time and slowly effect the engine's efficiency. They require constant fiddling if one is keen on keeping the engine in an optimal state of tune at all times. I have had misfire issues with both standard and high-tension sprung breaker points. The problem promptly was solved once I went with points conversion systems. Normally, distributor main shaft thrust clearance will not increase by more than a few thousandths over the life of the engine, which makes the runout issue moot in all cases but for the more demanding owners such as I.