Cam and valvetrain longevity....??? low duration high lift...
09-28-2016 | 07:14 AM
#582
Frank's Marine Service
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From: Elkton, MD
What carb and intake are on the engines?
09-28-2016 | 07:20 AM
#583
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From: bel air, md
lots of things to ck over without out question but given both engines nearly identacle I still say intake manifolds assuming cams degreed correctly but it sounds like you confirmed that. Not enough spring pressures and or lifter failure woulda showed up on dyno. What springs are you using? Johnson lifters correct?
09-28-2016 | 08:13 AM
#584
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From: bel air, md
Actually I think Tim could keep his carbs. They should have a dual bolt pattern. I think the 4150 intake is killing the signal to the boosters of the carbs. Usually when the large 4150 style carbs are used for "class racing" with the 4150 intake flange they end up opening up the entry of the intake.
09-28-2016 | 08:21 AM
#585
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From: cleveland ohio
We used a dominator intake with a 4150 carb.
We cut an inch off the brodix HVH 2002 manifold and drilled and tapped it for a 4150.
It had a "cast in place" spacer, so to speak, so we had plenty of material to work with.
I also have hatch clearance issues.
We cut an inch off the brodix HVH 2002 manifold and drilled and tapped it for a 4150.
It had a "cast in place" spacer, so to speak, so we had plenty of material to work with.
I also have hatch clearance issues.
Last edited by vintage chromoly; 09-28-2016 at 08:38 AM.
09-28-2016 | 08:24 AM
#586
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From: Central IL
What would Zul do for induction? I'm seeing scoops under the Christmas tree this year. 
09-28-2016 | 08:28 AM
#587
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From: bel air, md
That's exactly how I would go about it if I had clearance issues to deal with.
09-28-2016 | 08:31 AM
#588
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From: chicago
How much power you think he will gain from just an intake swap?
09-28-2016 | 08:42 AM
#589
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From: Olmsted Falls,Ohio Marblehead,Oh
09-28-2016 | 09:01 AM
#590
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From: bel air, md
My guess is 20-30. I think you could also get the same results with a lot of grinding on the opening of the intake. To the degree of what was done to Rob's intake in the picture. But I think the motor would be much happier throughout the rpm range... I really believe a 4150 intake does not belong on a 500"+ motor. Neither does a Vic. jr. or 454r/o.
