fast intake vers. ls2 90/92
Ok how about this one Dave:
The LS2 intake can be ported in 2 ways: porting the runners to match the heads and porting the guts of the intake to allow for more volume within.
Now people have ported the runners and gotten 5-10 rwhp. Then they ported the guts of the intake and got another 5-10 rwhp. Yet they did not touch the runners the second time, so where did this power come from? If what you're saying is true, as in you can cram as much air in the intake as you want, it's still going to be limited by the runners, then this idea would not work. But people have done it, keeping the runners the same size and shape, and only improving the volume of air in the intake and they gained power.
So the same works for the LS6 with the bigger TB opening. Sure that doesn't improve the actual flow thru the runners, but it allows for more air to enter in the bowls of the manifold that then is available for the runners to take.
The LS2 intake can be ported in 2 ways: porting the runners to match the heads and porting the guts of the intake to allow for more volume within.
Now people have ported the runners and gotten 5-10 rwhp. Then they ported the guts of the intake and got another 5-10 rwhp. Yet they did not touch the runners the second time, so where did this power come from? If what you're saying is true, as in you can cram as much air in the intake as you want, it's still going to be limited by the runners, then this idea would not work. But people have done it, keeping the runners the same size and shape, and only improving the volume of air in the intake and they gained power.
So the same works for the LS6 with the bigger TB opening. Sure that doesn't improve the actual flow thru the runners, but it allows for more air to enter in the bowls of the manifold that then is available for the runners to take.
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Besides volume one has to take into account velocity.
same issue when it comes to heads. many thought for awhile that larger runners meant automatic increase in power, while the truth of the matter, shape of runners and ability to increase velocity as well as volume is the key. That is also why not all valve jobs are the same.
same issue when it comes to heads. many thought for awhile that larger runners meant automatic increase in power, while the truth of the matter, shape of runners and ability to increase velocity as well as volume is the key. That is also why not all valve jobs are the same.
First of all David, you're the one that came out talking smack because you simply do not understand it.
you're even unwilling to read info from people who have done it and seen improvements.
There was even way back an article in a magazine that swapped various TBs and intakes, the best (not by much) was a 90/90 FAST, then came TPIS 90/modified LS6, then oval TPIS TB with LS6, then just plain LS6.
There is plenty info on Corvette Forum as well.
BTW the graph above was from a stock internal Z06 and Crane 1.8 rockers (1.8 rockers were on before intake swap and after).
As I said I used a prototype BBK 85mm and my intake modified by TPIS and I saw a good 15rwhp across the curve. So it does work.
you're even unwilling to read info from people who have done it and seen improvements.
There was even way back an article in a magazine that swapped various TBs and intakes, the best (not by much) was a 90/90 FAST, then came TPIS 90/modified LS6, then oval TPIS TB with LS6, then just plain LS6.
There is plenty info on Corvette Forum as well.
BTW the graph above was from a stock internal Z06 and Crane 1.8 rockers (1.8 rockers were on before intake swap and after).
As I said I used a prototype BBK 85mm and my intake modified by TPIS and I saw a good 15rwhp across the curve. So it does work.
OP,sorry for mucking up your thread...end of subject for me.
Can't say that agree with what you stated,but you have a right to your opinion. Now if the method of porting the "guts" as you call it was actually that effective then wouldn't all of the major porters of manifolds do that as a standard practice on the FAST and LS6 as well? There comes a limiting point where porting is no longer going to be a benefit,but will actually become detrimental to the flow of the manifold,that's why it takes a expert porter to know where that line of limitation exists.
Yes there is a limiting point to this, I agree there. But I don't think the limiting point of LS manifolds is 78mm and anything more than that is not going to really do anything.
Can't say that agree with what you stated,but you have a right to your opinion. Now if the method of porting the "guts" as you call it was actually that effective then wouldn't all of the major porters of manifolds do that as a standard practice on the FAST and LS6 as well? There comes a limiting point where porting is no longer going to be a benefit,but will actually become detrimental to the flow of the manifold,that's why it takes a expert porter to know where that line of limitation exists.
What?
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