sloppytot

Hey all. Some might have seen a few posts from me this week regarding the purchase of a '97 SS. Anyway, I will be looking to give it a boost in HP as my budget allows. First on the agenda is exhaust. It currently has had the ram air intake changed to SLP cold air intake. Has the SLP 2OTL cat back from SLP, but the muffler was changed out to a Spintech muffler to reduce highway drone. The seller is providing me with Hooker shorty headers that he was planning to install. While it's nice to have the headers included with the purchase of the car, it presents me with some questions that I need to ask myself (and you all). While originally planning to buy an LS1, I am already starting off with less horsepower than I had planned so I want to maximize every bit of horsepower possible. I have two paths I can take. Install the hooker shorty's, eliminate the cats with off road pipe, and be done with the exhaust. OR... I can sell the hooker headers, buy a set of longtubes (maybe Pacesetters unless I decide to spend more money for higher quality), and enjoy the maximum horsepower. Of course, being in NY, I will have to throw the stock headers back on every 2 years for emissions. Someone told me that after 16 years old, the car doesn't get tested for emissions or something. Basically said that I will be fine due to the car being a '97 and not requiring another inspection until 2016. Another issue to keep in mind is that the car is on BMR lowering springs (1.25" but real world, about 1" drop). Was told that some brands long tubes will be scraping very easily.

So what is everyones recommendation? And if anyone has info on NY's emissions testing, feel free to share. I would love to be able to go with long tubes, eliminate the cats and not have to worry about swapping out the parts to pass inspection every 2 years.

Thanks!

Z28Freak86

I would have to do some reasearch into new york state emissions testing, but a good pair of mid lengths (like pacesetter) should be completely fine for emissions testing in any state. They retain all the emissions equipment (EGR, AIR), and also keep the cats in the stock location. Their primarys are a little longer then the shorties, then the y pipe will be at least 3". If you have to pass the visual inspection where the emissions are hooked up and cats are in the stock location, then these headers would work without having to take them off. If thats the way that i understand how your emissions work, then the midlengths would be the largest you could go without moving the stock cats, and also your ground clearance would still be ok (only my clamps hang a little low, but i could turn them to give me some more clearance if i needed to). Just my thought, you could just was well go shorties and have no issues as well, you might again some hp and torque going a little bigger tho. Again not 100% sure about what your emissions requirement is, so dont quote me on that, but i know california is the strictest around and they allow those headers to be left on. I mean why not, they actually reduce emissions according the their carb sheets. http://arb.ca.gov/msprog/aftermkt/de...eo/D-439-7.pdf

sloppytot

Thanks for the info. I officially got the car last night and the Hooker shorties did indeed come with the car. However, if I can safely pass emission testing with mids, then I will just sell the hooker shorties and go that route. I was originally looking for an LS1 but when I came across this LT1, I just couldn't pass up such a find. However, now I am trying to milk every bit of HP I can to make up for the fact that I went with an LT1 instead of LS1. But man, I love this car!

Injuneer

You still need to find out what your local emissions requirements are.

If they require that the headers retain the stock cat locations (this is part of the Federal emissions law, which some jurisdictions do not enforce) you will be limited to the very few CARB-EO certified dual-cat headers, whether they are called shorties or mid-lengths. These can be problematic, producing high heat loads to the engine compartment. I think SLP was the most practical CARB dual-cat header, but I don't know if they even make them any more.

AS&M makes some great mid-length headers (I use them on my 800HP nitrous setup), but they had two designs - a single-cat and a dual-cat. Eventually they stopped making the dual-cat design because they melted everything in the engine compartment. A buddy of mine bought a set of used AS&M dual-cat headers, and they came with the thermal blanket the guy had installed on his firewall to protect things. My buddy added more thermal blankets, and he still melted stuff under the hood. He dumped them for a set of SLP extrude honed stainless steel stock style manifolds (he had a "friend" at SLP). The extrude honed manifolds are very rare.