cfgioja

iTrader: (2)

I have seen some of the threads for this 90mm ls6 intake. I can not get the link on the page that describes how to modify the ls6 manifold to work.

does any one have it, this is the only thing left that will be restricting my engine. I have headers, ls6 heads, dual springs, 90 maf but the air will still be bottled necked at the intake.

any help would be nice

Mike Morris

iTrader: (55)

Don't know how to do it but these guys sell it

www.tpis.com

SOMbitch

iTrader: (8)

TPIS cuts the snout off an LS6 IM and epoxys a 90mm opening on it. I think this is what you are asking>>>> http://www.tpis.com/parts/view/39

david vericker

iTrader: (1)

Has anyone ever done a dyno comparison between the stock LS6 manifold and the modified 90mm LS6 manifold? You would think that if the gain in HP is all that great,then the manufacture would be publicizing this to the hilt.

BIG_MIKE2005

iTrader: (116)

I'd say its basically pissin in the wind IMO. Especially with the mods the OP listed. With those mods a ported stock TB or aftermarket 85mm would be plenty on a stock LS6 intake. That intake is only gonna flow so much. I wouldnt waste my time making that a 90mm, if you want a good 90mm intake buy a used Fast & sell your LS6 intake.

Did you swap LS6 heads on & leave the stock cam? Or is there a cam not listed on your mods? I'm not seeing enough there to make your LS6 intake be the bottle nack of your combo. Well except your tryin to use a 90mm MAF. What TB are you running? Do you have one yet to bolt to a 90mm intake?

Darkman

iTrader: (2)

I picked up 15 hp with the TPIS 90mm intake with a stock LS2 90mm throttle body over a stock 78mm LS6 intake. My LS6 had a PatrickG spec'd EPS cam (218/230/.600” 116L SA), and stock exhausts.

(I have since added Trickflow 215s among other things and will be going to a FAST 102 intake keeping the same 90mm throttlebody.)

cfgioja

iTrader: (2)

I still have to purchase a cam.

If 15 hp is all the difference is I will just keep my regular setup. I was looking into this to see if it was even worth the trouble to do. But I believe with the car I am running it wont make much difference.

Thanks for the advice.

09camaro383

iTrader: (2)

agree with BIG_MIKE2005!! and to Darkman the only difference between the ls2 and ls1 intake is the opening but they both have the same plenum volume they both suck!! and you gain 15hp because you change to a ls6 intake that has more plenum volume, the larger opening doesn't help because the intake only gonna flow so much. Why do you want a 102mm intake and a 90mm throttle remember is all about the flow and you going to have more intake volume but a restriction in front??

SOMbitch

iTrader: (8)

Here is a compare with several intakes including an unported FAST 90>>>>> http://www.tpis.com/pages/2_17_06

Blow it up bigger to read it....

Darkman

iTrader: (2)

Perhaps I was not clear. My motor is an LS6. The 15 hp gain was an LS6 90mm intake with a 90mm LS2 throttle body (the after) versus an LS6 78mm intake with a 78mm LS6 throttle body (the beofre). Thus, the gain came not from any change in intake design or capacity, but purely from the increased throttle body size.

Before the change, extensive dyno testing (wtih PatrickG doing the tuning "on the fly") indicated the 78mm throttle body, in and of itself, was a restriction such that I was making the same horsepower at 6,500 rom that I was making at 5,200 rpm with the 78mm throttle body. The power curve carried well after 6,500 rm, it was just "flat". The 90mm throttle body showed the 15 hp gain entirely between 5,200 rpm and 6,500.

headed-ws6

iTrader: (34)

OP I have had the intake for about 6 months with a NW 92mm TB and it is awesome. I am on stock heads and cam but the throttle feels more responsive then it did with the ported TB. I am very impressed with the intake and it was 3-4 hundred less then the fast. But as stated the ls6 can only flow so much in the end.

david vericker

iTrader: (1)

What is your set up (combo)? There's nothing in your sig to indicate the power potential of the engine. How is a power "curve" consider flat at 5200 rpm to 6500 rpm?. Obviously it is no longer a curve and thus indicates a maximum power level has been achieved. Something wacko is going on here,because I posted earlier in the day on another thread about a 383 with a LS6 intake that flat lined at 5300 rpm and he also blamed the intake.

As I stated in that thread My 78mm FAST with a TB that is compatible with LS6 intake (see my sig) pulls to 6600 rpm with a steady gain in HP (41) 440 to 481 from 5300 rpm to 6200 rpm then flat lines until 6600 rpm where it starts to fall off. The LS6 78mm intake cannot be that inadequate,something else appears to be wrong here. I would say that the cams are highly suspect in both of your cases...no way in hell is it your TB...if that was truly the issue then my engine wouldn't make it to 5000 rpm without flat lining.

Red99TA

iTrader: (11)

I think the TPIS gains are close to an unported FAST 90 but its not really cheaper if you buy used parts. You pay $350 for the intake modification and $350 for a 90mm TB ($700) whereas you can get the FAST IM/TB for $1000 (used intake plus new TB) and sell your LS6 intake and TB for say $300 and you're also out $700. So technically you could end up paying the same for the FAST setup which has more potential with porting.

NemeSS

iTrader: (127)

spend your $ on FAST intake if a ls6 intake wont cut it for your application. price range will be the same when it all totals up

garygnu

you can get a fast 102 mm intake for $850.

Darkman

iTrader: (2)

The "combo" was an LS6 (in a 2005 CTS-V), with Random Technoolgy high-flow catalytic converters, and the cam mentioned in my first post above.

The horsepower curve, which is actually the product of a decreasing torque curve multiplied by an increasring rpm/hp factor, was not merely "considered" to be flat, it was in fat, "observed" to be flat (with the usual minor flucations). We tested various changes to the intake system upstream of the throttle body, none of which alleviated the flat-lined results. The assumption at that point was simply that the combo was exhaust restricted (no headers) and the 90mm intake/throttle body change was actually just an experiment that happened to net an increase in hp.

I have not tested a ported 78mm FAST and therefore cannot speak to whether it is "compatable" (or comparable) to and LS6 78mm intake.

Darkman

iTrader: (2)

A $200+ change in fuel rails can also be required.

LaBLKv6Z

iTrader: (13)

A 92 MM TB will fit on the Dorman LS2 intake also.

wannafbody

iTrader: (2)

DLS2 is the best bang for the buck and has supported at least 522 documented hp. Not shabby. The Fast 102 might make 12 hp at peak more for a another $850.