LS6 intake manifold restriction?
#1
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when does the intake manifold become a restriciton?i was doing some math on non boosted cfms and boosted cfms at diff boost levels and with my setup ill be well over 1000cfm's so when DOES the intake become the restriction?
#4
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FWIW our shop car ran 8.9 @ 153 with the FAST intake, 78mm throttle body (the 90mm tb would be of no gain). The base of the FAST intake cracked, so we installed an LS6 with the same throttle body and the car ran 8.9 @152.
So, it seems on our car at that level the intake was worth about 1mph.
So, it seems on our car at that level the intake was worth about 1mph.
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#8
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Originally Posted by Pro Stock John
I read or heard somewhere that running a TB/Intake setup that is bigger than the pipe coming from the intercooler does not make any sense.
#12
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thats interesting.im only looking for 600rwhp so its not like i could justify spending >$1000 for a 90/90 but has anyone infact flowed or found at what cfm it is a restriction.Smoking Hawk im suprised they could make that much on an LS6....i wont even be near that lol.Guess im just super curious when it is the next restriction in line.
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Originally Posted by ddnspider
thats interesting.im only looking for 600rwhp so its not like i could justify spending >$1000 for a 90/90 but has anyone infact flowed or found at what cfm it is a restriction.Smoking Hawk im suprised they could make that much on an LS6....i wont even be near that lol.Guess im just super curious when it is the next restriction in line.
To try to answer your question, the fact that you are pushing air through the intake via boost, you will likely never find a point that it stops flowing enough to make more power with added boost. You will eventually find a point where it will become worth while to upgrade, but I bet it wont be until you reach way beyond anything anyone is willing to try. One thing you will eventually find is the forward facing TB style intake will start to lean out the back cylinders at higher boost levels, I would imagine this is why the Ohio boys are using the diffrent intake.
-Bryan
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the reason smokin hawk listed is why I plan to run a single plane intake. I am willing to sacrifice some down low to get better air distribution and not have to worry about the back cylinders leaning out.
#19
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Originally Posted by black_z
What about the LS1 intake for a mild (500-600) HP street setup?
trying to remember but i think i made my 512rwhp on the mustang dyno with the ls1, i didnt get it redynoed after that. so i dont know what all gains i made.
#20
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i made the swap way back when from an LS1 to first an alum Weiland LS6 but didnt like the fact that it got as hot as it did at operating temps so i switched to an LS6...basically made money from the switch and its much cooler now.And that was what $300?that seems to make more sense than $1000 for a FAST thatll net me another 20-30 hp,especially on a street car.SmokinHawk ,I have heard alot about what you experimented with about the back 2 ports.But if you have a sufficient fuel system i would think or at least hope you could get around those 2 cylinders being lean especially with a good tune.So what i gather is that even though itll never get to the point that the intake itself will become a big restriction itself, there is a point where itll stop being capable of flowing all the air that your trying to push especially at higher rpms.Good discussion.