[pmr2000]

How many are on the V6's? Are they very restictive, does anyone make performance versions or is the exhaust upgrade good enough for a V6?

Thanks, have not had a chance to get underneath the front yet, too cold and cramped in the garage!

[psychobenz]

dont know about HP cats, but I have been to at least 15 shops in the last week (shopping) and about 11 of them were honest and said I did not need to change the cats because they do a pretty good job,the most restrictive part is the muffler and that i would only need to change them if I went FI.

[hotshot]

The V6 muffler is known to be restrictive. Thats why a lot of people upgrade to a simple GT take-off muffler than flows extremely well for an OEM part.

[fishingjts]

I picked up some nice gains by going to a custom off-road y-pipe... LOL!

The problem is the car sounded TERRIBLE!!! The nasty buzz from 3000 to 4000 was just plain WRONG! I highly recommend leaving the stock cats in place! There was a nasty buzz even when i stock high-flow cats back in...

[DevilNBluDress]

You don't need to remove the CAT if you go to the vortech web sitehttp://www.vortechsuperchargers.com/ they have a video and a article on a car called lil 6 it has 500hp with a stock engine and with the CATs on it is street legal too.

[stlwagon]

The cats actually flow very well on both the GT and V6.

[fishingjts]

Originally Posted by stlwagon

The cats actually flow very well on both the GT and V6.

I did get a descent gain taking the cats out... helped in the low to midrange... didn't help on the upper range:

http://www.v6john.com/Main/Performan...ypipe/dyno.jpg

I was stuck at 13 flat until we took the cats out.. then the car went 12.8...

[fishingjts]

Originally Posted by DevilNBluDress

You don't need to remove the CAT if you go to the vortech web sitehttp://www.vortechsuperchargers.com/ they have a video and a article on a car called lil 6 it has 500hp with a stock engine and with the CATs on it is street legal too.

Yeah... 500RWHP with a BIG SHOT OF N20! Watch the video again and you'll see the nice Zex kit installed! Look for the purple Zex nozzle in the top of the after cooler right before the exit!

They are also running 16 PSI on race fuel... don't try this at home kiddies! LOL! And yes, the motor is stock... but what they leave out is that it is not the original motor... they have popped more than one 4.0L...

And in case your wondering... I have seen "Lil 6" more than once... Paul runs FFW... so I know what i'm talking about... LOL

[stlwagon]

Originally Posted by fishingjts

I did get a descent gain taking the cats out... helped in the low to midrange... didn't help on the upper range:

http://www.v6john.com/Main/Performan...ypipe/dyno.jpg

I was stuck at 13 flat until we took the cats out.. then the car went 12.8...

I picked up a little across the entire band when I swapped mine for race pipes.