Fresh 331 Oil Issue Help


Jul 23, 2017
Hello, I used to have an account here but I havent had a fox for a bit and forgot my password...

I really need help, I just finished a 331 stroker on my 88 notch ex georgia police interceptor. When I purchased the car it was a 306 with edelbrock performer intake and heads, 24lb injectors with matching maf, bbk shorties and 5 speed with a A9M and older chip.

I dropped the new motor after having it honed and boiled by the machine shop, I rebuilt the heads with new valves (due to damage after the 306 gave way), it has new bearings and I have the scat 331 kit, I put a set of long tubes on. After dropping the motor in and getting it all buttoned up I was able to start the motor and it ran strong however there was alot of smoke and oil smell, at first I thought it was the rings seating but it has not gotten better. I went through 2 qts of oil in the past day just running it to set the timing and take a run around the block. I have done some searching and realized I have oil in the vacuum lines, I took off the upper intake and found about a half quart of oil in the intake. The pcv valve also had oil and no screen, the only modification I did to the intake was a bbk half inch intake spacer but it has no egr hole in the center, the egr has been bypassed on this vehicle, any idea if the center egr hole would make more vacuum to the intake? Thank you!
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SN Certified Technician
Aug 27, 2012
In the garage
you need the PCV screen
what are your bearing and ring gap tolerances
Who did the machine work
Are the heads or intake milled
what cam- hyrdraulic- roller, solid
New valve seals?
Any other vacuum leaks?


Jul 23, 2017
In the process of getting the pcv screen, I cannot remember what the bearing and ring gaps were but they were all within spec of the scat kit, all lower end is brand new. Machine work was done by a very reputable local shop, the cam is an f-303 that i reused from the 306, valve seals were all perfect and no other vacuum leaks, I did not have this problem prior to the rebuild/ stroker.

edit, I was very meticulous about this build because I want this to last, I followed the manufacturer instructions regarding ring placement to a T.
Last edited:


Jul 1, 2017
Could be the rings didnt seat properly.What valve covers are you using?If there are no baffles,maybe oil is being sucked into the TB.


New Member
Jul 20, 2017
Do a compression leak down test. This will tell you if the ring seated correctly or not. To me sounds like they didn't bc from what your telling use it's using a lot of oil which I would say is blow by from the the rings.


Jul 23, 2017
Compression test on a cold engine was between 150 and 175 psi. I'm taking the intake back off to do a baffle similar to the explorer intake to see if it's pushing past the stock baffle do to the high volume oil pump. My vacuum is pulling 14 psi off the tree, I may reroute the vacuum line to under the upper intake runner instead of at the back and see if it helps.


10 Year Member
Mar 2, 2003
Greenville, NC
My dad had a 302 rebuilt several years ago and it sucked down oil like crazy after the rebuild. The engine builder tracked the issue down to the PCV system on the Chinese Cobra intake he was running. Like yours it was pulling tons of oil through the PCV. They fixed it by removing the PCV valve from the lower intake and installing it in the drivers side valve cover.


I leave the horn on while driving
5 Year Member
Apr 26, 2010
Is there supposed to be a freeze plug in the oil valley under the intake at the rear? I did not put one in but it appears to have a place for one.
Yes, if that is missing, you will shoot oil straight into the pcv valve. A buddy had the same thing happen to him.

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