bent1

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?

2000Hawk#317

iTrader: (3)

I have heard before that the FAST intake is very simular to the LS6 intake. I have never had a tune before so sorry that I can't help you there. WTF am I talking about....I haven't helped at all. lol My bad

lemons12

iTrader: (71)

I actually laughed at this post.. Almost sig worthy.


The ls6 and the FAST intakes are nothing alike, especially the 102. They fit the same motor and that is about where that ends. LOL

dtsti

iTrader: (6)

Was it the same dyno?

Stippy17

iTrader: (5)

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.

lemons12

iTrader: (71)

Same dyno, same tuner... Graphs looked similar throughout the curve. He is adding a cutout in the Y.

Old Geezer

iTrader: (3)

Quik test: Drop the exh off of the LT's and test again.

oange ss

iTrader: (50)

that stock I-pipe is def not helping the cause

2000Hawk#317

iTrader: (3)

Yea I try...lol But I really have heard that the LS6 was very simular to the FAST. I said it backwards last time. When you said FAST 102, you did mean TB right? You said it twice if thats the case. Just curious. Good luck with the gains though.

Midnight02

iTrader: (8)

Not sure we understand what you're trying to say. To clarify, the stock LS6 in nothing like the FAST 102mm intake....night and day difference between the two. The FAST intake would also be mated with a larger throttle body too, however that's a separate part from the FAST intake.

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.

bent1

yes Fast 102 with a 102 throttle boby

bent1

ordering cut out today

soundengineer

iTrader: (16)

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.

Nemesis350

iTrader: (11)

I agree with this^^^

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.

bent1

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.

My90Iroc

iTrader: (26)

Dumb question but when the fast setup was installed did they adjust the throttle cable properly and ensure you're getting 100% throttle?

edcmat-l1

iTrader: (10)

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.

edcmat-l1

iTrader: (10)

This is a legitimate question, although I would think if it wasn't opening all the way, the power difference/loss would be more.

soundengineer

iTrader: (16)

I have never had a FAST intake not make more power than an ls6 intake...and I've tuned hundreds of them...

Even if you have a restrictive stock exhaust, you still make more power with a FAST intake than you do with an Ls6 Intake

2000_SS

iTrader: (24)

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.