sleeper setup (itr/ls)

[siciliani]

i did my homework, and spent the last several hours using search and looking at old threads. here i stand with, as far as i can tell, an original thread.

here's what i learned: all exhaust elements make some power, but none are magic, so don't expect miracles (and hp accounting doesn't work). if you're gonna do it, do it all. itr stuff will fit an ls.

now for my question: i'm planning on running a n/a sleeper LS with moderate gains (minor future mods only), weekend autox, but daily driver. NOT TOO LOUD IS CRITICAL! before my research i was thinking of an itr catback, but now i've decided i need a header and cat, too. i recently found a full itr header/cat/catback for sale. so, along with my intake, would that itr header/cat/catback be a good setup for my needs? it appears that itr parts are the best of both worlds for me (good flow and not too loud). what kind of change can i expect: more low end pull, higher top end power, etc? will i lose power anywhere?

sorry this is so long, but 1greyteg always wants to know people's expectations, and tuan always bitches about newbie's not doing their homework and using search.

thanks,
p

[drPheta]

glad you did you homework.

the itr catback (which i have on my ls now) is pretty decent. Junk the header and cat since they're only 2 inches (which will be pretty restrictive for your hp needs down the road).

additionally, the beginning of the b pipe on the itr catback is 2 inches (like only a 1 or 2 inch strip). go to honda - tech . com and search itr catback and you'll see what i'm talking about.

as far as gains are concerned, i couldn't tell you cause the butt dyno lies from day to day. however it is definitely a boost from the tiny straw the ls comes with. the itr catback is 2.25 inches all the way through (minus that little bit in the beginning).

to make the stainless steel piping even better, get a muffler shop to chop off the beginning of the itr b pipe and weld on a 2.25 inch piece and flange. get a carsound cat (part # 94005) that's 2.25 inches, and get a good quality header.

now the muffler...it's an ok muffler, and nothing to pay much money for. if you can get it cheap, go for it...it's still freer flowing than stock gsr, or stock ls...but it's not like the big boys...once again, enough for your hp needs.

keep in mind though, if you aren't expecting more than 200 hp out of your car, this is fine...once you get near 200+ hp, better start lookin for 2.5" exhausts for n/a and 3" exhausts for turbo.


anybody else have to add to this...be my guest...and correct me if i'm wrong anywhere in there.

[1Greyteg]

If you plan on staying @ or below 180 to 185 WHP then the stock R's catback should do nicely and fit your requirements. Be advised though that it Does have a bottleneck that will impair the highest flow possible.

As per the ITR header, I would suggest the JDM OEM header instead of the USDM model, for 2 reasons; The US model is heavy as HELL and the The JDM has shown nicer gains across the board and especially up high in the RPM. You may lose a little low end Tq but, you can afford to lose a few. You could also use the OEM heat shield for the JDM header for a nice clean stock look but, still having gains. The Cat, I would toss the OEM cat, and go for a Carsound. It simply has better flow, may be a little more expensive but, you get what you pay for.

If you are planning on exceeding the 185 mark and you MUST seriously decide this before embarking on your project, then:

Toss the OEM/ITR stuff and step up to the Big boy Toys IE: Well designed header with longer primaries and a 2 1/2" collector to mate to an equally sized Carsound cat and then mated to a matched well designed catback;"Hytech, SMSP, Kakimoto-R!"

You also really didn't mention cams or the like but, if you are really going for a sleeper N/A Ls then cams will be knocking on your door soon enough. Just remember the exhaust piping diameter/power rating rules... Don't go too small now and need to upgrade in the future. Seems though that you are starting to plan nicely.

Good luck,

A.

[siciliani]

thanks guys. per your advice, i'm going for the itr catback for now. how will i be able to tell how far back the 2" bottleneck goes? is it inherently obvious for me (or the redneck at the muffler shop) to spot and take out? i couldn't find that link on honda- tech.com

this will be fine for my current plans, but you mentioned cams...would this exhaust be too restrictive in case i DO decide to think about cams? again, 185whp is fine. would cams be the next logical step?

lastly, will the carsound cat give me more noise or emissions? we have to get tested here in the land of beautiful horses and fast women.