Hi, Im a new member with a 97 SS and it has Edelbrock shortie headers on it now but Im wanting to go with a set of Mid lengths that keep the egr/air and being in NC I need to keep the cats. What would be a good mid length to look into that come with high flow cats?

 

Any mid or long tubes will move the stock location of the cat, which will technically fail you on the inspection part of smog. If you can find a smog shop that is only interested in the sniffer or has no idea what to look for, then you should be fine with a catted y-pipe. I hear Mac and Pacesetter are very popular brands for mid tubes. Both can be bought with AIR/EGR hook ups.

 

They arnt too technical here, as long as the cats are under the car it will pass our inspections. I had an SRT and it did have a cat but the placment of the resinator made it look like a cat so it always passed. We dont even have to do the sniffer, just need the cats.

 

Are these the mac Mid lenght your talking about http://fasttoys.net/shop/product_inf...roducts_id=476

 

If your inspection only cares that there is a cat located under your car then I would go with the mac's but I would get the 94 style single cat. If I remember correctly the 94's have a little bit longer tube length and flow alot better. I will say that the plug access on those headers is awesome.

 

Will the single cat flow ok? Also is the link I posted above the Mac Mids you guys are talking about? They are all Ive found but it doesnt say mid length.

 

yes those are the mac midlength headers. If you do a search you will find a lot of info on why the 94's are a better design. If you do get them I would recommend getting them from jet hot. I got mine four years ago and with about 30k miles put on them they are still looking as good as the day I bought them. Don't quote me on this but I think that the total price I paid was around 525 coated. I am sure you could probably pick up a set of the headers and y-pipe cheaper used though.

 

The SLP, MAC or ASM are the best bet in a mid length. The ASM are closer to a longtube than the others and will make more power. Here are the ASM headers.

 

THanks alot guys, Does the engine have to be jacked up to get mids on?

 

No

 

Unless your superman.. Yes...

 

The "single cat" MACs don't require the engine to be jacked up. But if you go single cat with an OBDII car (>1995) I think you'll have to do something about the O2 sensors. Eliminators/simulators or reprogram the ECU.

 

Anyone have any info on the eliminators, Im guessing Ill need to extend one O2 to the cat and get an eliminator for the other or just eliminat both of them.

 

JMG97SS:
Since nobody is responding, I'll take my best guess! The OBDI MACs would use your front O2 sensors. Passenger port is at the collector and driver is on the Y-pipe (I seem recall ... I'll take a look later and post if it isn't). You'll use the sims to replace the ones after the convertors that OBDII uses to check the condition of the convertors. I believe some people have said the rear O2 sensors can be programmed out and then the simulators wouldn't be needed. Some have also said the simulators are only resistors (don't know the values) that return the signal of an O2 sensor reading at the exit of a properly functioning convertor. Hopefully one of the OBDII LT1 experts or moderators will clarify. Good Luck

 

Don't go Mac, go AS&M...1 3/4" primaries are better than 1 5/8" primaries...even if you're stock.