LS1GTO.com Forums

**vegitaGTO** · 03-14-2009, 12:56 AM

Pretty soon I'll finally be getting some Kooks headers. My question is would I need to close my cutouts before I get the Kooks installed and the car tuned or can I leave the cutouts open? Or does it really matter? I already have some Magnaflow mufflers installed.

**JETNITRO** · 03-14-2009, 02:04 AM

Tune it for which ever way you will be running the car most of the time,This way you will get the best HP gains.

**vegitaGTO** · 03-14-2009, 07:57 AM

Ok, with that being said, has anyone picked up any real gains with there cutouts fully open because I run mine open 99.9% of the time.

**Lothar-[Tech Spec]** · 03-14-2009, 11:10 AM

I just had my car on the dyno yesterday to test this! I had won a GC for two free dyno pulls to I had them do one with the cutouts open and one closed (the car was tuned before I had the cutouts).

The car made about 6hp and 8ft*lbs more with the cutouts open, and that was from about 3500rpm on up.

**corvetteandsilverado** · 03-14-2009, 10:07 PM

I don't have cutouts but my buddy has an 98 t/a and he dyno'd more hp and tq with them open I think with just his cutouts he made 312rwhp and 328rwtq I can't remember what he made with them closed but I know it out dyno'd my vette when I had a cat-back system

**ShoddyHog** · 03-15-2009, 04:31 AM

All this talk about cutouts. You guys are going to get me divorced.

Gerry

**vegitaGTO** · 03-15-2009, 10:19 AM

Quote:

Originally Posted by corvetteandsilverado...


	I don't have cutouts but my buddy has an 98 t/a and he dyno'd more hp and tq with them open I think with just his cutouts he made 312rwhp and 328rwtq I can't remember what he made with them closed but I know it out dyno'd my vette when I had a cat-back system

Yeah some buddy's in the West TN F-Body Association were the ones that put me on to cutouts because I use to have an 02 Z28. Not sure if this is true I was told the F-Bodys' got more hp/tq gains because they weren't true dual systems to begin with. But with the current info from here, I'll probably leave them open when I get the Kooks on and the car tuned.

**vegitaGTO** · 03-15-2009, 10:19 AM

Quote:

Originally Posted by ShoddyHog...


	All this talk about cutouts. You guys are going to get me divorced. Gerry

Why a divorce? lol

**pharmdgto** · 03-15-2009, 10:25 AM

I need to get my cutouts tuned. I put them on last year and always run them open at the track so I have no clue the differences when they are closed. One this next round of mods, we will do the SD tune with the cutouts open.

**vegitaGTO** · 03-15-2009, 10:31 AM

Well, this will be my first time getting the car tuned. Combined with just my K&N CAI, Kooks and cutouts I hope to get some desent numbers.

**PirateGoat** · 03-15-2009, 10:44 AM

Quote:

Originally Posted by ShoddyHog...


	All this talk about cutouts. You guys are going to get me divorced. Gerry

I agree

Quote:

Originally Posted by vegitaGTO...


	Why a divorce? lol

I think he means he is wanting to spend alot of money on the car, and its gonna cost his wife getting pissed at him.

I have a cutout on my camaro and it put down 9 rwhp more with the cutout open compared to closed.

**6.0L rice eater** · 03-15-2009, 10:50 AM

UPS is bringing my DMH low pro cutouts tomorrow