So my car would be REAL loud because I would just be running an X-Pipe and Headers, and it just goes out from there... How could I still use an X-Pipe, and have it be legal? Thanks for all your help, Ryan

 

According to federal law.. no car with longtubes is legal. Cats can't be moved from the original location. I have cats in the stock location with my mac midlengths however.

You can go over the axle or under the axle to go all the way out to the bumper, but that setup will run you more than 600.

Oh yea.. my duals with two flowmasters (before cats) was quieter than the Off road ypipe going into a single flowmaster at low rpms.. only got louder when i got on it.

 

Well, how much hp would I gain going with Hooker Long Tubes, and a custom X-Pipe over stock? What would I gain going with Shorty Hooker Headers, an aftermarket Y-Pipe, and a Loudmouth Cat-Back over stock? Thanks, Ryan

 

http://laneswheels.com/images/12inch_flopro_pic.jpg

He put mufflers on after the X-Pipe, could I do that?

 

yes the mufflers go after the X.

SHorty headers won't gain you much at all. The stock manifolds on the Fbody's are pretty good.

Heres a comparison for you.

Flowmaster exhaust i trapped at 106

I went with mac midlengths with off road ypipe. my MPH went to about 108.5-109
opened a cutout on that setup (dumping before the axle) and i went to 110-110.5

I went to a true duals setup (still the mac midlengths) over the axle into two 40 series flowmasters (some of the poorest flowing high performance mufflers around, but they are quiet). I'm trapping at 109.8-110.5ish depending on how i drive that run and the weather of course.

Hope that gives you an idea of the gains... again check out ls1.com when it comes back up and do searches here and there

 

Alright, I kinda get an idea now, but if I ran Long Tubes, and then an X-Pipe and put some mufflers on the end of the X, would I be legal?

 

Not in Houston you won't. You'll need cats to pass inspection.

That another expense to cat delete systems, O2 simulators.

 

Well I guess I am just going to get a Y-Pipe then, I can't not pass emissions. What is the most power you can gain using a Y-Pipe setup? Could I use Hooker Long Tubes with a Y-Pipe? What Y-Pipe is the best? I think I am going to get the SLP Loudmouth Cat-Back because that seems to be what everyone else has, is that the best one? Thanks, Ryan

 

Like I said, pick up the Nov issue of GM High Tech Performance and look at the cars running in the LS1/LT1 shoot out. There are 4 running mid-low 11's w/ long tubes, a y pipe to single pipe exhaust. Look at the GMMG built Camaros and Mechams (even the models making over 400 hp), they all have the y pipe to primary pipe set up. A good single set up flows more than enough for 90% of the cars out there, but then you wouldn't be able to claim you have a "true dual."

 

The reason is cost, not flow. The differences in flow aren't worth the additional cost. If you find me one ypipe setup that sounds better than true duals however, I would like to hear it


To answer his question about legalities.. I repeat, by the letter of FEDERAL emissions laws, no longtube headers are legal. However you can throw cats on just about anything and it will probably pass emissions testing. I have cats on my xpipe in the stock locations (which technically makes it legal)

 

Hooker LTs,y-pipe and loudmouth is one of the loudest setups I've heard.You still are unlikely to pass emissions like that.Duals are deaper sounding and have less resonance.I am running stock manifolds,o/r pipes and a D/D exhaust.I also have a cutout and when it is uncapped it is very loud and raspy.Pretty much what LM is with no cats.When it is capped it sound a little louder than stock.I like this setup alot.I can't wait to hear it with some Pacesetter LTs.