No HP gain after costly mods. bad tune or exh?
#1
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No HP gain after costly mods. bad tune or exh?
before latest mods: prc stage I heads, MS3 cam, 42lb injectors, ls6 intake, long tube headers, 3" y-pipe, stock intermidiate pipe, magnaflo muf, stock tail pipes.
Dyno=405rwhp/363torque
today added: Fast 102 with Fast fuel rails, 102 tb, no MAF and running speed density.
todays dyno=406rwhp/360torque
Are these heartbreaking results due to a bad tune, restricted stock intermidiate pipe and tail pipes or could it be something else? This latest mod was very expensive for me to get no results. Can anyone help me figure this out?
Dyno=405rwhp/363torque
today added: Fast 102 with Fast fuel rails, 102 tb, no MAF and running speed density.
todays dyno=406rwhp/360torque
Are these heartbreaking results due to a bad tune, restricted stock intermidiate pipe and tail pipes or could it be something else? This latest mod was very expensive for me to get no results. Can anyone help me figure this out?
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Same dyno?
Do you have the graphs, and can you post them up? You may not have gained any peak hp, but you may have gained some down low or in the midrange.
I would say ditch from the intermediate pipe back because it is a restriction on your setup, or add a cutout after the ORY. Either way you will gain whp.
Do you have the graphs, and can you post them up? You may not have gained any peak hp, but you may have gained some down low or in the midrange.
I would say ditch from the intermediate pipe back because it is a restriction on your setup, or add a cutout after the ORY. Either way you will gain whp.
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#10
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It definitely sounds like something is awry. I'd be curious to know what numbers it puts down through the cutout. That would help answer the question about whether or not its an exhaust restriction.
#13
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Its in the Tune... you should have picked up atleast 10-15 RWHP...
no granted, the exhaust might be holding you back some...but you should still see some difference in the results with a change from a measly LS6 intake to a FAST 102...even if you had a 2" exhaust you would still see some difference
with the exception that maybe the dyno was set to STD instead of SAE....then it could have 2 days the same because of weather...
make sure the Dyno is SAE corrected so that weather doesnt effect the results.
no granted, the exhaust might be holding you back some...but you should still see some difference in the results with a change from a measly LS6 intake to a FAST 102...even if you had a 2" exhaust you would still see some difference
with the exception that maybe the dyno was set to STD instead of SAE....then it could have 2 days the same because of weather...
make sure the Dyno is SAE corrected so that weather doesnt effect the results.
#14
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Its in the Tune... you should have picked up atleast 10-15 RWHP...
no granted, the exhaust might be holding you back some...but you should still see some difference in the results with a change from a measly LS6 intake to a FAST 102...even if you had a 2" exhaust you would still see some difference
with the exception that maybe the dyno was set to STD instead of SAE....then it could have 2 days the same because of weather...
make sure the Dyno is SAE corrected so that weather doesnt effect the results.
no granted, the exhaust might be holding you back some...but you should still see some difference in the results with a change from a measly LS6 intake to a FAST 102...even if you had a 2" exhaust you would still see some difference
with the exception that maybe the dyno was set to STD instead of SAE....then it could have 2 days the same because of weather...
make sure the Dyno is SAE corrected so that weather doesnt effect the results.
and fwiw...I think what was said above about the FAST intake being the "same" as the ls6 intake is just a misinterpretation of expected gains. I know alot of people that think they'll gain 50 hp from ANY fast intake they spend a GRAND on, only to net 5-10hp, or not even "feel" a difference. People have to understand that some mods are NOT POWER ADDERS, but better yet compliment setups that would otherwise be restricted by "less-capable" components.
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Just to update, I havent been back to the dyno yet but I will post the dyno numbers as soon as I get them. I had developed an oil leak with the last dyno run and have it apart waiting on knock sensor grommets. The catch can was connected backwards also.
#17
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You don't "tune" a FAST intake. Unless it flows significantly more air to cause a lean condition. It either makes power or it doesn't. If the A/F is in range, the tune is pretty irrelevant to whether it makes power or not. You should be able to bolt it right on and make power.
Some engines do not benefit from a FAST intake simply because they do not require the additional airflow the intake is CAPABLE of flowing. The engine is the pump, you're just trying to help get the air in. There can be several reasons for it to not need, or want more air. The intake, by itself, does not make power.
Some engines do not benefit from a FAST intake simply because they do not require the additional airflow the intake is CAPABLE of flowing. The engine is the pump, you're just trying to help get the air in. There can be several reasons for it to not need, or want more air. The intake, by itself, does not make power.
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I would take a closer look at the before/after dyno graphs and look for gains in the 2000-4500ish range. The tune should not make a huge difference, gains would be seen regardless of the tune, provided it was good from the start.
Maybe you have some mechanical issue hindering power? It would seem ironic that its holding you back to the exact same power you made before the intake swap though...
I say if no issues are found and you have no future plans for the motor, you might as well put the LS6 back on and sell the FAST to recoup some funds. I've heard of them not gaining much or any power, but i thought that was on square port heads? I would expect gains on your setup, but if the heads weren't restricted too much by the LS6 intake before then it might not gain much peak power.
Maybe you have some mechanical issue hindering power? It would seem ironic that its holding you back to the exact same power you made before the intake swap though...
I say if no issues are found and you have no future plans for the motor, you might as well put the LS6 back on and sell the FAST to recoup some funds. I've heard of them not gaining much or any power, but i thought that was on square port heads? I would expect gains on your setup, but if the heads weren't restricted too much by the LS6 intake before then it might not gain much peak power.