Compression test results

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Think while I have the plugs out I'll continue down the path of replacing valve seals, then seems like alot of diagnostics are in order
 
TT5.9mag said:
Not a bad plan. But, those plugs are so sooted up it’s hard to tell if they’re burning oil. Hell it could be fuel fouling that one plug the PO was talking about.

Holley 37-485 Renew Kit Carburetor Rebuild Kit
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Hmmm, I'm not gonna lie the idea of not having to do valve seals now is very enticing. . .so maybe a better path would be to figure out what's going on with the carb
 
If it were mine I would yank the valve covers and have a look at the valve seals closely and see if I could visually spot a problem on all of them. That would determine which path I’d take.
 
GREEN GHOST said:
Right now it actually sounds very "cammy" at idle which I like. .maybe the 750 is way jetted up or timing retarded
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it sounds cammy because the idle mix is too rich. the plugs point that direction too.

do what PRH said, rebuild the carb. stock jetting as a starting point. read alot about tuning carbs. set the idle mix after the motor is at running temp.
 
So to mix things up and add even more confusion another thought was to convert to sniper EFI . .
 
Also a good chance that either the power valve or valves are blown or they have been plugged and the carb is running 8-10 jet sizes larger.
 
GREEN GHOST said:
Think while I have the plugs out I'll continue down the path of replacing valve seals, then seems like alot of diagnostics are in order
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Good plan.
Reading plugs is a tricky deal. You don't want to read plugs that have a lot of idle time on them. The plugs need to be fresh and the car run at wide open full load to sort out the main system( main jets and power valve circuit). Same for timing at wide open throttle. Not a simple task. And you have plenty to figure out before you go there.
Your fouled plugs could also come from the idle circuit set incorrectly. Assuming the carb is working as it is supposed to. The timing at idle could be incorrect. This would be a good place to start after you replace the plugs and check the basics.
There are many other problems that could cause your plugs to foul out. I don't know your experience level but you may need to have a reputable "tuner " have a look at it. Do all that you are comfortable doing first and see where you end up. Check and confirm the basics first before you start replacing expensive parts. Good luck
 
GREEN GHOST said:
So to mix things up and add even more confusion another thought was to convert to sniper EFI . .
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I would make sure the motor can be made to run properly on a "good" carb before you try fuel injection. It will be handy to know that the engine is sound before converting. You may also find that you are perfectly happy with how it runs with the carb weighed against the cost and extra work of installing fuel injection.
 
Do you have blue smoke out the pipes (especially when it's cold!) or any other indicators that the valve guides or seals are bad? Do you know if the heads were purchased ready to run and bolted on or were they purchased bare and assembled by an experience builder who checked guide to stem clearance, did a proper valve job, checked and equalized the spring pressures and set the springs to the proper installed height? If I see a relatively fresh build and it's burning enough oil to make the plugs look like that, I would have already pulled the heads off to see what was happening. But it sounds like you have a reason to change the fuel tank and other parts of the fuel system besides them being 12 years old that you may not have mentioned. Is it fouling fuel filters? Is it possibly gacked out to the point of having stuck the floats open? If your not seeing any major signs of oil consumption, then I would go ahead and go through the fuel system before doing anything else. Also, what brand and what number of spark plugs? It looks like you have an MSD distributor and a blaster 2 coil, are you running an ignition box with that? MSD recommends .050 of plug gap with a 6AL or Digital 6 box now.
 
I wonder if having the breather plumbed into the air cleaner can be making the engine ingest some oil through carb. . .
20211228_150657.jpg
 
Garrett Ellison said:
Do you have blue smoke out the pipes (especially when it's cold!) or any other indicators that the valve guides or seals are bad? Do you know if the heads were purchased ready to run and bolted on or were they purchased bare and assembled by an experience builder who checked guide to stem clearance, did a proper valve job, checked and equalized the spring pressures and set the springs to the proper installed height? If I see a relatively fresh build and it's burning enough oil to make the plugs look like that, I would have already pulled the heads off to see what was happening. But it sounds like you have a reason to change the fuel tank and other parts of the fuel system besides them being 12 years old that you may not have mentioned. Is it fouling fuel filters? Is it possibly gacked out to the point of having stuck the floats open? If your not seeing any major signs of oil consumption, then I would go ahead and go through the fuel system before doing anything else. Also, what brand and what number of spark plugs? It looks like you have an MSD distributor and a blaster 2 coil, are you running an ignition box with that? MSD recommends .050 of plug gap with a 6AL or Digital 6 box now.
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Doesn't seem like excessive smoke, how ever on start up I noticed some oil resude from the exhaust pipes. Haven't started the car in a couple weeks. It's running an msd 6al, billet distributor, & msd coil. I also noticed the plug wires are 12yrs old and look like garbage, some cracking in boots & 1 terminal came off. See plugs below
20211227_070252.jpg
 
Those are the plugs I ran in my nitrous motor. My car runs better n/a on a 5 or 6 extended plug. Also running that rich will trash rings. Ask me how I know.
 
aaronk785 said:
Those are the plugs I ran in my nitrous motor. My car runs better n/a on a 5 or 6 extended plug. Also running that rich will trash rings. Ask me how I know.
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So the part number for the extended tip plug is either 4096 or 4095 . . . .come to think of it previous owner said "nitrous was supposed to go on the car" but he didn't want to run it
 
It doesn’t need the race plugs(R series).
Just get some BCPR6ES from the parts store.

Before you commit to changing all the seals, you may want to test the waters on how much fun that job is by replacing the one that’s theoretically bad first.
 
PRH said:
It doesn’t need the race plugs(R series).
Just get some BCPR6ES from the parts store.

Before you commit to changing all the seals, you may want to test the waters on how much fun that job is by replacing the one that’s theoretically bad first.
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My thoughts exactly going to start with supposedly the bad cylinder and see how it goes.
 
@GREEN GHOST you're going in 15 different directions. Sit down, clear your head, come up with a plan and focus on one thing. And that one thing should be making what you have work properly. That engine in that car should meet (or exceed) your goals as it sits. Forget about a cam change, an intake change, and efi for now. Bolting on parts doesn’t fix problems.
 
From your picture in post 47 it looks like you have a pcv valve in the driver side valve cover. If that’s correct and it’s working the breather connected to the air cleaner is correct and is filtering the air ENTERING the crankcase. It’s plumbed correctly, and not causing the engine to injest oil.
 
TT5.9mag said:
@GREEN GHOST you're going in 15 different directions. Sit down, clear your head, come up with a plan and focus on one thing. And that one thing should be making what you have work properly. That engine in that car should meet (or exceed) your goals as it sits. Forget about a cam change, an intake change, and efi for now. Bolting on parts doesn’t fix problems.
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Yeah, I realized that earlier today. I have to divide and conquer. . Just seems like everything is intertwined & I don't want to spend money twice . . I'm going to tackle the valve seal, then new plugs / wires, then look into carb & timing
 
TT5.9mag said:
From your picture in post 47 it looks like you have a pcv valve in the driver side valve cover. If that’s correct and it’s working the breather connected to the air cleaner is correct and is filtering the air ENTERING the crankcase. It’s plumbed correctly, and not causing the engine to injest oil.
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Got it
 
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