Stem Pocket Lines on 502 MPI Intake
#1
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Joined: Jan 2009
Posts: 721
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From: Algonac MI
Considering running -8 lines from the rear of the intake to the front to eliminate steam pocket in the rear of the heads. Has anyone ever done this to a 502 Mag MPI Intake? It looks awful tight on the starboard side to drill and tap in the rear of the manifold.
#6
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Joined: Aug 2011
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From: bel air, md
Sounds like it needs more fuel. What does the cylinder look like? If I was going to run lines of the back of the intake I would use -4 definitely not -8. But I think you have a problem with your tune-up
#7
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Joined: Jan 2009
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From: Algonac MI
Thanks guys wasn't sure if the water lines would help or not. I believe my main problem was I was getting up to around 10 lbs. boost on the stock iron heads. Replacing heads with dart aluminum 325 and see where that puts me.
#8
Id like to see how that injector flows compared to the rest , you will prob find your prob there. I have seen severe differences on both used AND new maggeti marelli/fiat style 502/454 injectors. I flow and clean injectors and Im local to you, Smitty
#9
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Joined: Oct 2010
Posts: 922
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From: Hemlock, MI
Hadley, I would have Smitty look at your injectors if they haven't been tested in a couple years. Couldn't believe how bad mine were after I roasted a BONE STOCK 502 MPI this summer. Had 4 real bad and 2 more not acceptable. We replaced with Siemens/Deka 63 lb/hr and re-tuned to compensate. Did a quick patch up on the engine and beat the crap out of it rest of the summer.
#10
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Joined: Aug 2011
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From: bel air, md
Hadley, I would have Smitty look at your injectors if they haven't been tested in a couple years. Couldn't believe how bad mine were after I roasted a BONE STOCK 502 MPI this summer. Had 4 real bad and 2 more not acceptable. We replaced with Siemens/Deka 63 lb/hr and re-tuned to compensate. Did a quick patch up on the engine and beat the crap out of it rest of the summer.




