fouled plugs

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hiapolikana

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Hi all, i recently had a set of 906 heads reworked and since installing i noticed my plugs on my pass side are fouling very badly. Before i had the heads done i didnt notice the fouling but i honestly cant really remember. my question to you all is...How can i verify what is causing the fouling? i am guessing a leakdown test, going to order it this week. I already did a compression test and all cylinders are between 170 and 175 psi.

Forgot to add this is a 383
 
SOunds to me like it's running fat. Let's see what the leakdown test says. Your CC looks good.
 
Bob: yes everything is new. i am hoping it is something simple but i am worried after finding a very bad review of work done by this particular company...
 
that's looks like oil fouling to me. you might have oil coming down past the stem seal. see if he put the proper seals on. the seal should be tight on the guides and not the umbrella seals on the intake, the exhaust doesn't matter. the proper seals will have a noticeable edge on the top and the umbrella seals are rounded at the top. the umbrella seals do no fit fight to the guide and are only used on the exhaust.
another thing is oil maybe coming down pass the guide where it was pressed into the head after drilling for it. if the bit gets too hot the press fit will be wrong and not as tight as it needs to be.
 
If you are running manifolds and the heat riser valve is stuck closed, there's your huckleberry.
 
RustyRatRod said:
If you are running manifolds and the heat riser valve is stuck closed, there's your huckleberry.
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Agreed.

One other thought would be a mismatched intake to the heads sucking oil past the gasket.

Just saw the headers post, sorry.
 
#6 & #8 plugs look almost identical, 2 and 4 are fouled but not as bad. dont have pics of the other ones. if i get out of work early enough today ill take pics of the valve area and other plugs
 
a 906 head is a big block right? so I don't think its a intake problem If it has a alignment problem it will suck air not oil so that leaves only 2 problems . a leak down test won't show either. oil control rings or valve seals only way oil can get into cylinder.(unless your fuel pump is putting oil into the fuel but not likely)
 
TrailBeast said:
Agreed.

One other thought would be a mismatched intake to the heads sucking oil past the gasket.

Just saw the headers post, sorry.
Click to expand...

this may be your problem since it's all on one side or at least the gasket didn't seal. remove the intake and have a look see. oil can come up from the valley under the steel shim gasket real easy, use plenty of glue.
 
What valve stem seals were put on and are you running an aftermarket cam? I've seen the stock umbrella type get smashed up with larger lift cams. Dual or single plane intake? PCV system?
 
Thank you for all the replies, got voluntold to work this weekend so trouble shooting will have to wait till next weekend.
 
So i finnaly had a chance to diagnose the old girl. From the leak down test i am getting oil past the rings. Looking at doing the rebuild i have come to the conclusion that i will be building another short block instead of doing this one.

Question to you all is i have spoken to a engine builder and he quoted to build me a 400 zero decked with the following
Machine work; bore/hone, square deck, align bore, resize and shot pen rods, kb-240 pistons, moparperformance 7qt pan, meling hv oil pump, an ATI dampner and solid flat cam (specs up for debate) for 4k. Does this seem reasonable?
He is also telling me with my current heads (906 stage 1 port, standard valves) and a .550ish lift cam i can look at 500+ HP and torque. Is he blowing smoke up my @ss?
I am undecided on whether to do this or a 451 Stroker from Musclemotors. cost wise is within $700 of each other. This is my daily driver, and i would like to run low 12s in street trim and slicks.

What do you all think?
 
451 from MM's. No brainer there and it'll go low 12's with ease in an a-body
 
A 400 cubic inch daily driver with that big of a solid flat tappet cam (252-256 @ .050) will not be very pleasant. It is also doubtful that the 906 heads in a stage one configuration will support 500 HP in a 400.

Here is a 440 dyno run on line #25 with stock heads in about a Stage 2.23343 port job with stock size valves. Notice it doesn't crack 500/500.

http://www.forabodiesonly.com/mopar/showthread.php?t=261378

I too am thinking the Muscle Motors is the better choice of the two choices you are asking about.
 
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