What power will this combo make?
#1
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Join Date: Apr 2010
Location: Newcastle, Australia
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What power will this combo make?
Guessing game.
Build:
Lightly ported otherwise stock BP4W Head
1,900cc
NA8 Inlet manifold, ported cnc spacer to match port head
Absurdflow low mount style manifold 1.25" runners
GTX2976r 0.86
Full 3" straight through exhaust
8.6:1 forged bottom end
Boundary pump
Enough fuel, intercooler, intercooler piping, intake, gearbox, diff, clutch etc for 500whp
Premium Unleaded.
What do you all think?
What will be the limit, detonation or outright flow? Valve seat pressure? RPM?
Dann
Build:
Lightly ported otherwise stock BP4W Head
1,900cc
NA8 Inlet manifold, ported cnc spacer to match port head
Absurdflow low mount style manifold 1.25" runners
GTX2976r 0.86
Full 3" straight through exhaust
8.6:1 forged bottom end
Boundary pump
Enough fuel, intercooler, intercooler piping, intake, gearbox, diff, clutch etc for 500whp
Premium Unleaded.
What do you all think?
What will be the limit, detonation or outright flow? Valve seat pressure? RPM?
Dann
#3
I wouldn't waste your time with the NA8 manifold, not sure I've ever heard of it being an upgrade. Spend your time and money on converting a Honda short runner intake.
Hope you have a transmission solution in mind cause it'll make more than the 6 speed can take. BMW trans solution should be out some time this summer I would think.
Hope you have a transmission solution in mind cause it'll make more than the 6 speed can take. BMW trans solution should be out some time this summer I would think.
#10
I would guess 350-370whp on 93 with a perfect tune, if everything else is perfect as well. If you added some meth injection, I think you could add another 50-80whp depending on how much meth you spray. You would be octane limited is my guess, and I would highly recommend valve springs. If the exhaust valves float, it can cause hot exhaust gasses to dilute and raise the temps of your air/fuel mixture during the intake stroke, and that can quickly cause detonation.
#12
I don't have part numbers for you, but someone makes valves springs that have a changing diameter. Springs with a constant diameter have resonate frequencies that can cause problems. Running 2 or 3 different size springs together helps, but a spring with a varying diameter is the best solution, and I have read post/seen pics of them here. I'm going to swap to better springs next time my cylinder head is off for service. I haven't run aftermarket cams, so no experience. They are not cheap is all I've really found in my research.
#14
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Join Date: Apr 2010
Location: Newcastle, Australia
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The easy button is just ST light doubles, about the cams, I think we will try without running new ones.
Hopefully we can just do ignition, water/meth and springs and just run 30-40 psi.
Dann
Hopefully we can just do ignition, water/meth and springs and just run 30-40 psi.
Dann