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Spark plug read and recommendations???

2K views 13 replies 7 participants last post by  boyd66k20 
#1 ·
Hi guys

My car wouldn’t start so I pulled the plugs. The rebuild 461 engine has about 350 miles on it with a lot of garage idoling prior to being road worthy.

I’m using AC R45TSX plugs gapped at 0.045. The engine has a Voodoo FT 60203 cam and a Holley 780. I haven’t yet tuned the Holley so that may be a cause too (running rich?). Engine oil consumption is about 1/2 Quart since changing after cam breakin. Plugs 5,7, and 2 appear a little oily?

Thoughts on plug choice? Oil consumption?
 

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#6 · (Edited)
I Understand that. Does it appear to be a timing or carb tuning issue? Forgot to mention, it’s also has a Pertronix II with there coil as well
 
#9 ·
It is possible to have a blown power valve.

Just my opinion but I try to avoid resistor spark plugs (not at all saying that is why they are showing rich) but you might consider NGK 2817 non-resistor spark plugs {for open chamber heads})
 
#10 ·
Looks like oil-fouled from here. Plug will smell like engine oil. The oil can come from the piston rings, valve stem seals or the positive crankcase ventilation (PCV) system. Leaking piston rings can be diagnosed with a leak-down test. If it's fuel, you'll smell the gas on the plug.

I see you are using oil 1/2 a quart in 350 miles is excessive. Maybe the rings need to seat yet???. See or smell oil burning smoke out the exhaust? If so when? If during deceleration, it can be valve seals.

What type of valve covers are you running and do they have a baffle to help keep the pvc valve from sucking in oil?

Are the oil return holes in the heads clean and free of debris?

Also smell and look at your oil, does it seem to smell like gasoline or appear thinned-out by gas?
 

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#11 ·
If the only time the engine has run is just cam break in and extended idling in the garage then those plugs readings aren't really a good example of the engines health or what's happening with your engine.I think extra run time idling in the garage doesn't really do as much good as driving it would do.A newly rebuilt engine NEEDS drive time to seat the rings, plain and simple.
If you're ready to drive it then put new plugs in drive it and then pull them to check em.BUT if you ain't gonna drive it for some months then just clean the old plugs and put them back in temporarily till you're ready to drive it.New plugs are just going to fowl out again so why ruin a new set ? JMHO
 
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#12 · (Edited)
Thanks for the feedback and support. I’m away this week, but plan to proceed as follows:
1. Install new plugs ???? Use same plugs??? AC R 45TSX?????
2. Inspect PCV and tubing.... replace if required.
3. Check timing
4. Tube Holley
5. Get some road miles on it
6. Will also get oil

Hopefully the rings are still breaking in. Oh, it has factory valve covers with baffles. Since all plugs look pretty similar, I’m hoping it’s simply breaking, idoling, and Holley tuning

Will pull the plugs at another 250 miles after some road time.

Again. Thanks for all the help.... I appreciate it.
 
#13 ·
Thanks for the feedback and support. I’m away this week, but plan to proceed as follows:
1. Install new plugs ???? Use same plugs??? AC R 45TSX?????
2. Inspect PCV and tubing.... replace if required.
3. Check tuning
4. Tube Holley
5. Get some road miles on it
6. Will also get oil

Hopefully the rings are still breaking in. Oh, it has factory valve covers with baffles. Since all plugs look pretty similar, I’m hoping it’s simply breaking, idoling, and Holley tuning

Will pull the plugs at another 250 miles after some road time.

Again. Thanks for all the help.... I appreciate it.
Check your pcv valve by rattling it. The valve inside, sort of bounces around when you shake it.
 
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