Where is the Restriction
#1
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Where is the Restriction
OK I was at a car show this past Saturday and I saw a guy with the Fast 90/90 setup and a stock MAF. How are you going to see a big gain with the Air is still going through 75mm MAF? I don't see a point in the Fast 90/90 unless people upgrade the MAF and LID with bigger opening. What am I missing?
#2
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You're missing that it's a series of "soft" restrictions,
not trying to fit a hard object through a fixed hole.
Remove what you can and leave what you can't.
The MAF (minus the "screen", which sucks) is a short
bit of smooth pipe and doesn't drop much pressure
at flows where it's still a useful instrument.
With manifolds you have each cylinder drawing a
big narrow pulse so it needs runner size during the
pulse, and otherwise it's wasted volume. But out in
the plenum and forward it's a smoother, averaged
flow and one 75mm hole can "support" 8 75mm dia
runners pretty much if each is drawing 1/8 of the
time (or effectively).
not trying to fit a hard object through a fixed hole.
Remove what you can and leave what you can't.
The MAF (minus the "screen", which sucks) is a short
bit of smooth pipe and doesn't drop much pressure
at flows where it's still a useful instrument.
With manifolds you have each cylinder drawing a
big narrow pulse so it needs runner size during the
pulse, and otherwise it's wasted volume. But out in
the plenum and forward it's a smoother, averaged
flow and one 75mm hole can "support" 8 75mm dia
runners pretty much if each is drawing 1/8 of the
time (or effectively).
#3
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Also remember as the air goes thru the MAF the airflow velocity will increase so the flow rate will remain pretty constant.
Bigger MAF's tend to show a cripser throttle response as opposed to massive HP gains.
480rwhp from a 75 to an 85mm MAF would probably see ~5rwhp +-3rwhp.
Bigger MAF's tend to show a cripser throttle response as opposed to massive HP gains.
480rwhp from a 75 to an 85mm MAF would probably see ~5rwhp +-3rwhp.