[L78toLT1]

Originally Posted by steelheadrob

I saw those cat delete pipes similar the CA performance ones. Not sure I want to go catless due to noise as you point out and some other have complained about a gas smell in the car. I think am going to get headers with hi-flow cats, probably texas speed. Just debating between the 2" and 1 7/8".

Is the noise noticeably different for connection pipes vs. High flow cats? I have kooks headers / cats. Just by looking at the cats, it does not seem like they would quiet things down much, if at all.

[Lemosine]

Its very noticeable for sure night and day difference.

[oldman]

Originally Posted by L78toLT1

Is the noise noticeably different for connection pipes vs. High flow cats? I have kooks headers / cats. Just by looking at the cats, it does not seem like they would quiet things down much, if at all.

I'm M6 like you. I have had two combos:
factory headers with CA pipes... stock rear cats
Long tube no cats
long tube with high flow cats

The last is by FAR the best sounding setup, the M6 really sounds terrible with no cats say 6th gear 55 MPH.. just BAD. With cats it sounds fine and pulls fine. I was always going to run cats, but wanted to tune it no cat incase I kill the cat with a bad tune.

[Joe's_cool_1le]

I destroyed my kooks hiflow cats in 4 months with my setup.

[oldman]

Originally Posted by Jhunsberger

I used the new era performance cat delete pipes, bought them thru weaponX.

http://www.neweraperformanceparts.co...ete-pipes.html

Nice quality and fit, the top 2 nuts on the driveside were close to the pipe making them harder to tighten than the others.

With all stock exhaust and the cat delete pipes it is REALLY loud and raspy, don't really care for how loud it is. Just ordered Borla atak axle back with their mid pipe kit and the resanators, hope I like the way it sounds with the borla stuff installed. I knew with all the cats deleted it would be louder but, geez it's alot. Should of just did headers and full exhaust from the start.

I did both the CA front cat deletes to the factory system and then LT without and then with cats to the factory system. I really think the M6 cars do sound better with front cats, or basically any cat very close to the header collector. Since I'm running the factory system cat back (single outlet pipes) I don't think the Borla mid mufflers aka x pipe is going to do it. The M6 to my mind just does NOT sound good without a cat bolted onto and directly after the collector.


Long story short, the only good sounding M6 setups to me are:
1) factory shorty and factory front cats
2) LTs and cat bolted to and directly after the collector


Any other combination sets up a strange mechanical resonance within the exhaust system.

[80sMetalDude]

I've been gone from forum for quite a while but after seeing this thread I really want to do something to my build.

Thinking Spring 19.

I have the Whipple and been enjoying the hell out of it but this thread is making me get the itch.

[Jhunsberger]

As posted in the 1/4 V8 fast list:

First passes with the Whipple. Pretty much left off idle and rolled into the throttle. Was fighting tire spin and wheel hop, this best pass was the only smooth pass I was able to make out of 4.

2017 1SS M6
Tires used on the pass: Continental Extreme Contact Sport 305/35/20
Performance Mods (if any): Whipple SC, LT4 Fueling, Roto-Fab Dry, stock headers, full cat delete, full Borla ATAK, tuned by CSP.
Race Weight: 3975# with 1/2 tank of 93 fuel
Category submitted for: Please List the Category or Category #5 M6
R/T.......... .252
60'............. 2.098
330'........... 5.107
660'........... 7.558
660’ mph... 101.49
1000'.......... 9.646
1320'.......... 11.409
1320’ mph… 128.18
Name of the track: Maple Grove Raceway
Date of pass: 09/20/18
Weather conditions: 69deg, 87% humidity, 29.97 Baro, 541.3 Elevation, 1533 DA.


https://youtu.be/fz65A5-YASM


I am ready for some drag radials now!

[steelheadrob]

Respectable time considering street tires and an M6. Drag radials will make a big difference.

[Jhunsberger]

Originally Posted by steelheadrob

Respectable time considering street tires and an M6. Drag radials will make a big difference.

What tire setup are you running? front and rear.

[steelheadrob]

MT ET Street SS 305/45-17 with 17x10.5 RaceStar DarkStar Wheels on the rear. Front is stock tires and wheels. The MT et street R are a better choice for weight and grip. I got the SS due to the better handling if I get caught in the rain on the way to or from the track
But will likely switch to the Rs once I wear these out.

[Jhunsberger]

Just bought a wheel and tire set-up for the track:

Front
Wheels: Race Star 92's 17x4.50 5x120BC 1.75"BS GLOSS BLACK
Tires: M/T ET FRONT 27.5/4.0-17

Rear
Wheels: Race Star 92's 17x10.5 5x120BC 7" BS GLOSS BLACK
Tires: M/T ET STREET R BIAS 28x11.5-17

This should help ALOT. Gonna take some getting used to letting it rip off the line, yet hopefully not break anything in the drive line.

Rear tires alone are 18lbs lighter each.

I called Race Star and they recommended I talk with Mike @ Kents hot rod garage for a wheel and tire package. He certainly took care of things.

[18ss376]

Great job, I plan on putting a Whipple on mine.

[steelheadrob]

Originally Posted by Jhunsberger

Just bought a wheel and tire set-up for the track:

Front
Wheels: Race Star 92's 17x4.50 5x120BC 1.75"BS GLOSS BLACK
Tires: M/T ET FRONT 27.5/4.0-17

Rear
Wheels: Race Star 92's 17x10.5 5x120BC 7" BS GLOSS BLACK
Tires: M/T ET STREET R BIAS 28x11.5-17

This should help ALOT. Gonna take some getting used to letting it rip off the line, yet hopefully not break anything in the drive line.

Rear tires alone are 18lbs lighter each.

I called Race Star and they recommended I talk with Mike @ Kents hot rod garage for a wheel and tire package. He certainly took care of things.

This should make a big difference in both grip and weight. I have debated going with a similar skinnies set up on the front but I have a 30 mile drive to the track. Let me know what you think after you are able to run the set up some.

[JANNETTYRACING]

Originally Posted by Jhunsberger

As posted in the 1/4 V8 fast list:

First passes with the Whipple. Pretty much left off idle and rolled into the throttle. Was fighting tire spin and wheel hop, this best pass was the only smooth pass I was able to make out of 4.

2017 1SS M6
Tires used on the pass: Continental Extreme Contact Sport 305/35/20
Performance Mods (if any): Whipple SC, LT4 Fueling, Roto-Fab Dry, stock headers, full cat delete, full Borla ATAK, tuned by CSP.
Race Weight: 3975# with 1/2 tank of 93 fuel
Category submitted for: Please List the Category or Category #5 M6
R/T.......... .252
60'............. 2.098
330'........... 5.107
660'........... 7.558
660’ mph... 101.49
1000'.......... 9.646
1320'.......... 11.409
1320’ mph… 128.18
Name of the track: Maple Grove Raceway
Date of pass: 09/20/18
Weather conditions: 69deg, 87% humidity, 29.97 Baro, 541.3 Elevation, 1533 DA.


https://youtu.be/fz65A5-YASM


I am ready for some drag radials now!

Congrats good Job driving.

Ted.