DRAG cast mani boost spike?
#1
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DRAG cast mani boost spike?
I'm having some boost spike issues and gone over everything only thing i can think of is teh mani and the WG placement anyone else have this issue? i thought it was my boost controller @ 1st but i unpluged it and just running WG ( 10lbs ) then goes to 12 then 15 pounds.
#3
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Re: DRAG cast mani boost spike?
Yes, due to the wastegate placement on the DRAG manifold, boost spikes do occur. I've experienced 2-3psi spikes when using a DRAG manifold. Try to find a manifold with a wastegate that is centrally placed, like a Blox, or better yet an InlinePro.
#5
Honda-Tech Member
Re: DRAG cast mani boost spike?
Where is your vacuum line from the wastegate coming from? If it's coming from the intake manifold to the WG move it to the turbo nipple. I ran mine this was and didn't have any creep or spike issues.
#6
Re: DRAG cast mani boost spike?
Check your vacuum lines for a crack or a leak. Mine got slightly torn and would overboost. I thought it was the wastegate placement but I was wrong. Keep in mind this is a revhard cast manifold but the wastegate is in the same place (on one runner). I was able to hold 7psi with no creep on a 38mm gate
#7
Honda-Tech Member
Re: DRAG cast mani boost spike?
also be aware that boost spike and boost creep are two different things. poor wastegate placement can cause both.
creep - boost continues to increase in upper rpms (past your wastegate setting). or in other words the wastegate isnt releasing enough exhaust gas so boost continues to increase
spike - boost jumps up past your wastegate setting before settling down to the regulated pressure. basically the wastegate opens late causing a breif spike in pressure
the drag mani would be more prone to spiking IMO because the one runner does not have enough pressure to open the wastegate until too late. but also as stated above a quality wastegate and good boost reference and you should be fine at lower psi
creep - boost continues to increase in upper rpms (past your wastegate setting). or in other words the wastegate isnt releasing enough exhaust gas so boost continues to increase
spike - boost jumps up past your wastegate setting before settling down to the regulated pressure. basically the wastegate opens late causing a breif spike in pressure
the drag mani would be more prone to spiking IMO because the one runner does not have enough pressure to open the wastegate until too late. but also as stated above a quality wastegate and good boost reference and you should be fine at lower psi
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