PhilAndrews

'51 Chieftain - Getting back to it

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11 minutes ago, carbking said:

Not sure why one would add the complexity of dual points unless trailered race car.

 

It's what was available in my case. But, also my car is running 12V on an alternator too. 

Electronic doodads really do not like the constant switching of the high-voltage cutout on the regulator for a dynamo; the gradiated electronic regulator of an alternator is mich more smooth despite it being more RF noisy. A looped ferrite core on the output lead helps significantly for that.

 

I know originality etc but heck, alternators are so much better that dynamo generators, particularly on a slow-turning engine.

 

Phil

Edited by PhilAndrews (see edit history)

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Benefits of AACA Membership.

Thanks gang, informative as always! I'll double check the points before summer.

I always wanted to check the valve clearances. Maybe will do that one day too. 

I always thought that the engine should work as designed or they wouldn't have designed it to begin with. 

Adding "whizbangs" just doesn't seem right or turning a 6 volt into a 12 or converting drums to discs.....besides, where's all the fun in that??

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Valve clearances are critical on this engine, being as it it's slow and has a large overlap with a relatively soft cam- having them set wrong affects when they open by quite a margin. While not really perceptible at speed, it really makes a difference to low speed running and idle.

 

Phil

Edited by PhilAndrews (see edit history)

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10 hours ago, carbking said:

Not sure why one would add the complexity of dual points unless trailered race car.

 

If you should decide on an electronic whizbang, upgrade from your generator to an alternator FIRST.

 

If you decide not to get the alternator, and do get the electronic whizbang, don't call when you have an erratic or no idle.

 

Jon.

no complexity to going with dual points, first point does the opening, second point does the closing equals less wear on the points, gap adjustment last longer, and the coil builds up max voltage. I prefer old school technology in automotive ignition system. 

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A Pontiac 8 doesn't turn fast enough to really take advantage of the extra coil charging time, so the chief advantage of dual points will be that they will run a lot longer between tune ups. That would be a good reason too do it.

 

On the other hand thinking dual points might solve driveability problems is a recipe for disappointment. It wont help, and it might complicate efforts to find the original problem.

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Thinking on the original complaint, it may just be something as simple as a failing coil; sudden change in timing and combustion pressure may be causing the spark to blow out when pressing the gas to pull away (vacuum advance kicks in when coming off idle). Coupled with heat soak after a long run making it break down and become unreliable.

 

I would say pull a plug and spin it over when you can, take a look at the spark and see if it's a good strong bluish white, if it's bordering on orange, change the coil and try again.

 

If not, try tweak the distributor clockwise a fraction and see if it improves...

 

Phil

Edited by PhilAndrews (see edit history)

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5 hours ago, PhilAndrews said:

I would say pull a plug and spin it over when you can, take a look at the spark and see if it's a good strong bluish white, if it's bordering on orange, change the coil and try again.

 

You know now that I think about it, I think that's the coil that came with the car. I pretty much replaced everything but that. I remember taking off the NAPA sticker on it so I assumed it was a newer part. It never hurts to replace old with new especially when it don't break the bank.  

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6 hours ago, Bloo said:

A Pontiac 8 doesn't turn fast enough to really take advantage of the extra coil charging time, so the chief advantage of dual points will be that they will run a lot longer between tune ups. That would be a good reason too do it.

 

On the other hand thinking dual points might solve driveability problems is a recipe for disappointment. It wont help, and it might complicate efforts to find the original problem.

a Pontiac 8 doesn't turn fast enough ?, 4,000 rpms isn't fast enough ?

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4 hours ago, pontiac1953 said:

a Pontiac 8 doesn't turn fast enough ?, 4,000 rpms isn't fast enough ?

4000? I've never had mine above 3000.

 

No idea what the max sustainable RPM is but I'll take reliability and longevity, thanks.

 

 

--Phil

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Do you spin it 4000 very often? I was advised by more than one Eight owner to keep it under 3000 for extended periods. Nevertheless, I did not mean any sort of slight to the Pontiac 8. I am a fan of that engine.

 

Even at 4000 rpm on an 8 cylinder I can't imagine having too much trouble keeping a decent spark with a single point ignition. Over 5500rpm it might be really sketchy.

 

I'm not arguing against dual points either. If one of those dual-point aftermarket breaker plates were ever made for my 1936 Pontiac 6, I would be very interested. The 6 cyl. kits I see only fit the distributor Pontiac used from 1937 forward. What I am suggesting is that it is unlikely to fix anything that setting up the stock ignition wouldn't fix. Also, that if you miss somehow setting up the new dual points setup, you have added a second problem and may not know it. If you start with a good running car, you can instantly tell if something is not quite right with the new setup.

 

To paraphrase (heavily) 1990s ignition guru Christopher Jacobs, "The best thing an ignition system can do for you is light the fuel on time, every single time. If the engine is running well, you are already 98 percent there." In other words, beware of any claims of large percentage gains in horsepower, gas mileage, or driveability from an aftermarket ignition system. This coming from a guy who, by the time he said it, was selling aftermarket ignition systems....  All the best.

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7 hours ago, Summershandy said:

It never hurts to replace old with new especially when it don't break the bank.

The only time it hurts is the time it dosen't solve a problem that you have.  Then you don't know for sure whether it is aiding or abetting the problem.  

I have seen many people change too many things at one time and almost making it impossible to solve the real problem.

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4 minutes ago, Tinindian said:

I have seen many people change too many things at one time and almost making it impossible to solve the real problem

 

I do agree. That's why before my car was road worthy but knowing the engine ran, I decided to rebuild/replace as many parts that I could before heading out and test driving it. I was never a fan of just driving a used vehicle not knowing how good the parts could be, especially a 65 year old one. My coil was one item that was overlooked. 

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7 hours ago, PhilAndrews said:

4000? I've never had mine above 3000.

 

No idea what the max sustainable RPM is but I'll take reliability and longevity, thanks.

 

 

--Phil

I have had my 53 268 with 3.08 gears up to 97 mph once, 80 mph was 3016 rpms, 90 was 3393 rpms, I think my 59 389 engine going into my 53 and changing the gears to 3.23 at 90 mph the rpms would be 3555 a long ways down from a 6500 rpms reline. 97 mph works out to be my old 53 268 was turning 3657 rpms.

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I have a mysterious benefactor!

20200229_171650.thumb.jpg.1f504fade741426b5a10381c83002963.jpg

This arrived in the mail today, which looks absolutely excellent. 

 

Thank you!

 

Phil

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35 minutes ago, PhilAndrews said:

I have a mysterious benefactor!

20200229_171650.thumb.jpg.1f504fade741426b5a10381c83002963.jpg

This arrived in the mail today, which looks absolutely excellent. 

 

Thank you!

 

Phil

awesome gift.

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On 2/22/2020 at 12:05 AM, pontiac1953 said:

Yes, sure looks familiar, my 1955 287 Pontiac distributor with the same dual points conversion. 

20200221_235820.jpg

I was able to find and buy a nos Mallory dual point conversion for 1950 to 1956 Pontiac distributors, even came with the nos big trash can condenser that Mallory made. can't wait to get it in the mailbox.

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6 hours ago, pontiac1953 said:

I was able to find and buy a nos Mallory dual point conversion for 1950 to 1956 Pontiac distributors, even came with the nos big trash can condenser that Mallory made. can't wait to get it in the mailbox.

 

20200303_075439.jpg

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The ball race is between the plates to allow the vacuum motor to operate smoothly?

 

Phil

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Posted (edited)

Yes. One should be sure there is grease/oil on the balls and races so they don't rust. Ball bearings are more mechanically stable. Factory setups with ball bearings had trouble due to rust and wear (usually caused by lack of maintenance), and in some designs the damage would be to the housing itself. The factory systems on some makes switched from bearings to a pivot. Pivot systems last a lot longer when neglected, but the dwell changes when the vacuum advance moves.

 

That looks like a very nice high-quality piece in the pictures.

 

Edited by Bloo (see edit history)
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20200307_215855.thumb.jpg.b51366ed3d53dc1dc33f527c04b88367.jpg

I refitted the slam panel, found some appropriate bolts and fitted the hood latch, connected the cable up and got it all adjusted. For the first time since I've owned it the hood now latches!

 

Phil

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20200316_133655.thumb.jpg.7a3fcc23a0f7640e7ff9814fb4f17213.jpg

Ordered a decent set of plug wires. USA made, said the description.

Made in Mexico, says the box.

 

Oh well. They'll be better than what's on the car right now, for sure.

 

Phil

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20200320_213255.thumb.jpg.5c8682fa4db1048c1241b319b8118f42.jpg

My spark wire carrier was all dented up courtesy of the previous keeper (engine must've fallen over onto it) so I took it apart and beat on it with hammers.

 

Question for y'all, what shape should the lower part of the distributor lead-out there be? A mirrored curve or a flat piece? Mine is missing and I've no idea what it should look like to make another.

 

Phil

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This picture is the best I could find. Looks probably flat.

 

9746133_0.jpg

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Its curved to match the top piece. Keeps the wires in line.. ill get ya a picture with some dimentions later today... John.

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Posted (edited)
7 hours ago, Bloo said:

This picture is the best I could find. Looks probably flat.

 

9746133_0.jpg

Yeah, I'd found a couple pictures like that but all a bit inconclusive.

 

Thank you though! I may end up making a flat piece, we'll see. Unless somebody has a spare?

 

Phil

Edited by PhilAndrews (see edit history)

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