hey guys i know its probably in the search menu but thought I could just get a quick answer!

I have a 99 LS1 T/A and I really want a set of Headers. I know I want Coated Pacesetter LT's, now i just need an exact list of what i will need with the headers.. I know i want to keep the cats so will i need like high flow cats or something? please help

1) Set of Pacesetter Coated Long tubes
2) My choise of ORY
3)
4)
5)

 

Search would help but try the stickies here first: https://ls1tech.com/forums/forumdisplay.php?f=6

This site usually claims car sounds has a cheap and high flow cat.

I like the 'thunderbolt' that I got at Mr Muffler because it is high flow, small in size, and made of shiny stainless steel.

The Y - Pipe is debatable.

The cat back will be something you will want to hear different exhaust notes and such. I chose the Magnaflow and when I had Cats it sounded sweet. I am actually put cats back on with C5 O2 sensors since my stock O2 sensor were always throwing codes. Right now the O2 are delted and runningORY.

 

ORY = off road pipe, meaning no CATS.

Check out TSP (Texas Speed & Performance), thay have great deals on Pacesetters.

What you need:
-Coated Pacesetters 98-99 model year
-Emissions fitting if you plan on keeping EGR and AIR, if not race headers (they are the same thing minus emissions fitting, no performance difference)
-New GM metal exhaust gaskets, the paper ones supplied with the headers are junk
-O2 extensions, becuase the O2 bungs are further back
-The rear O2's are not present with LT's and will throw a SES light. You either need to have them deleted via a tuning software package (rolling road dyno shop) or you need to buy O2 Sims.
-TSP offer their own catted Y pipe, its well made and uses good high flow cats

Running aftermarket Y pipes like the TSP one sometimes result in the pipe banging on the underside of the car. Usually the fix is easy and should be done at the same time.

-Poly motor AND tranny mounts (available from Thunder Racing). These stop the engine torquing which causes the Y pipe to bang. They are also a great mod and will sharpen up the car also. The engine mounts are WAY easier to fit at the same time you do the headers, but a PITA afterwards
-Mufflex Y pipe hanger (Thunder Racing) this is an additional bracket for the Y pipe, it's not always needed, but for ~$40 it's worth getting.

Then all you need is a catback, which there's lots of choice. Check www.ls1sounds.com for sound clips/vids.

 

thank you for the post! that helps me out.. I don't feel so clueless into what i need for the project.

Right now i'm running kinda a dynomouth setup.. i cut off the stock muffler and had them weld a pipe there. and then before the pipe goes over the axle i had them place a dynomax bullit resistor muffler in its place. Would it be best to just buy a cat back? Or i could buy that tsp setup and have the 3inch piping all the way back with the bullit muffler. cause right now its stock piping

PS, where can i find a new gm metal exhaust gasket? The dealership?

 

Most of the parts are available from the sponsors, there's a list of them on the right when you are in the main forum page----->

Personally I'd want to up the tubing diameter to 3" for the catback, as smaller than that will pose a restriction, even more so with the more mods you do.

There's lots of choice for catbacks. Personally I like the SLP LM, it's really well made and is stainless steel. Its also very loud. Not to everyones tastes and it tends to be a love/hate setup. But with cats it should sound mean.

TSP offer the Rumbler, this is basically a LM knock off but in mild steel using a Dynomax bullet. But it is cheap and a greart alternative.

GMMG and Stainless Works both offer a very nice chambered exhaust in stainless steel. Not as loud as a LM but more toned.

Other popular setups include, Borla, Corsa, Hooker and Maganflow. Generally if you like the sound of the GMMG and LM types exhausts you may not be too keen on these, and vice versa.

But there are a lot of other exhuasts out there. The only one to probably avoid is the Flowmaster as it is quite restrictive.

There is one final option, which is dual exhausts. The Fbody floor pan isn't really designed for duals though so custom fitting is generally required. In short to get a stainless steel dual exhuast with cats is going to cost you more than a catback + Y pipe. If you're interested do a little searching or post up a question.

The biggest advantage to duals is sound. They do sound different to a Y pipe, but in all honesty the Y setups can still sound very good

Performance will be very similar between them until you get to around 420+rwhp IMO where the duals will be able to flow more than the Y pipe setup. But the HP varience is probably only minimal in most cases.

 

Thank you for all your help, i guess the next step after all that would be thinking about the installation..

 

It's all possible to do at home provided you have the correct tools. There are several articles on this site and others covering the installation.

Remember safety first, don't go crawling under your car with only a jack supporting it, you'll need axle stands, but access to a high lift will make it a lot easier. Might be worth getting a quote from some local shops and see how much it'll cost for the install.

 

good deal, where can i find those gm gaskets? and what is a good size for those extentions? 24" thanks again for all your help

 

I think Thunder Racing has most of the gaskets listed on their website, although I'm sure most of the sponsor are able to supply them. Failing that there's always GM dealers.