spark plugs.... Over thinking!

AuroraGirl

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All true except they use the factory vents. I'd love to find a replacement for the cheesy, delicate factory vents. I hate those things!
Pontiac spinny ones
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SirRobyn0

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If you had two identical vehicles except one had the factory AC (assuming it's working properly) and the other had the Vintage Air and you were sitting in the cab with the AC on with your eyes closed you couldn't tell the difference in performance.

However, when it comes to maintenance, repairs, installation there's no comparison.
For example:
a) VA has very few components and they are modular. It's plug and play. You get to lose the miles of OEM wiring, plastic connectors, dried out vacuum lines, hard to operate steel cables, finicky light bulbs, etc.
b) You get a modern, well designed Sanden compressor that's more efficient and reliable than the factory.
c) You lose the big obnoxious blower box on the firewall. It all goes away and gets a plate over it. Much cleaner. The VA is self contained and goes under the dash.
d) The availability and cost of R12 is cost prohibitive. 134a is dirt cheap and available everywhere.
e) The control panel is LED backlight and variable. The blower motor has infinite speed settings because it uses modern PWM rather than resisters in the airstream.

Vintage air is the equivalent of EFI for your climate control system. My only advice on doing a conversion is to buy the application specific "Surefit" system from the beginning. They make an Evaporator kit, A Condenser Kit and a general kit with all the ancillary pieces. Just by the full kit (which includes everything) and be done with it.

Drink beer and enjoy. This will take more than an hour to install.....I promise.
Thanks for the info. I knew some of what you said but not all. I'll talk to him about it next Wednesday when I return to the shop, as I will be staying away from that place for the next 5 days.
 

SirRobyn0

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Update:

Change of plans. I decided not to install the colder plugs after pulling these plugs and seeing what they look like. I pulled them all out and they do not look to hot, maybe a little on the hot side but not anything terrible, no fouling, and no oil deposits. While it is likely that I will return to the colder plugs in the next month or so I'm thinking the current ones look fine and the slightly hotter plug might help to burn off any carbon deposits in the cylinder. So keeping them in the short term.

Also figured out the WOT, pinging issue, and why I was thinking it was making a little bit better power after the intake gasket change. Spec for initial timing is 4 BTC. My notes say that when I bought it, it was timed at TDC, and that when I set it to the specified 4 BTC that it wanted to ping at WOT. So I backed the timing back to TDC, the ping is gone and so is that little bit of extra power it seemed to have which is disappointing, but at least I know I'm back to where I was (or maybe I should say I'm in a better place than where I was) back in flickin' February when the plug fouling started.

Also put a can of sea foam in the gas.

Ok this is just more encouragement for me to get my ESC system working, a project that I began back in February before the fouling issues started up and that had to become the priority. So probably no more spark plug updates, unless something unexpected changes. The ESC thread if your interested in here: https://www.gmsquarebody.com/thread...-knows-more-about-esc-system-than-i-do.33216/
 
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Redfish

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@SirRobyn0 thanks for taking us along on this journey. I learned a lot and of course we all love a Happy Ending. I personally would not have thought about the intake gaskets as a likely culprit but that is a big part of why I joined this forum, to learn from the "experts".

Hopefully you get the ESC working properly and we all get a good lesson from that too.
 

SirRobyn0

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@SirRobyn0 thanks for taking us along on this journey. I learned a lot and of course we all love a Happy Ending. I personally would not have thought about the intake gaskets as a likely culprit but that is a big part of why I joined this forum, to learn from the "experts".

Hopefully you get the ESC working properly and we all get a good lesson from that too.
I'm glad you enjoyed the Journey and learned something from it too. I knew it was possible for an intake gasket to suck oil, but didn't think it was what I had going on. I've been a mechanic for a lot of years and one thing I've learned is none of us know it all and we never will. The ESC thread link is in my last post and you should go check it out even though your 350 won't have one. It's well underway since I was working on that before the oil issue happened. Anyhow I've got a solid plan on the ESC and I think it will go smoother than the oil issue. With any luck I'll have it working before I go back to work on Wednesday.
 
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SirRobyn0

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Ok this will likely be my last spark plug update. So to summarize from the ESC thread, I've discovered my module behind the glove box is gone and the harness cut off. So I'd still like to get that going, but for now I installed an adjustable vacuum advance unit and tuned the overall timing a little bit better. It's happy at 16 degrees vacuum advance. With a base timing of 2BTC I'd get a little light pinging during a long hill climb at higher RPM, but was ok otherwise and the 2 degrees is noticeable vs TDC in the power department. Knowing that I haul with the truck, and tow the trailer, I decided to go ahead and go back to the colder plugs, primarily to give me a little bit of ping protection when pulling hills loaded. I did that all last week. Today I did a feed haul. This is about 2,500LBS of grain in the bed of the square. I'm happy to report that she did great. This is a route I've run many times before, and there are a couple of good hills on it, and it's still a 305 obviously but improvement in power was noticeable, especially part throttle power probably a combination of a working vacuum advance and an intake that seals up properly.

So that's it, unless something goes south I consider the spark plug issue solved.
 

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