I just installed an edelbrock cat-back and now I want to finish the exhaust up with pacesetter headers and had a few questions. First off, I will need them to be emission legal due to NYS emission inspections. I also want to go with the ORY and have cats welded in somewhere and have cut outs put in before the cat. I'm not worried about the location because out of all the places I've brought my car to get inspected, they have never looked under the car. I'm not sure if it would be better to get one big cat and put it in the I-pipe, or get something like 2 pypes mini cats and weld them into the y-pipe. Any suggestions on what the best cat to use is and where exactly I should put it? Also I've read that the coating on the pacesetters is known to flake off after a while. Once i'm back in NY, this car will not see snow. This car was clearly not designed to be driven in the snow. I had a new aluminized steel y-pipe put on my maxima before I moved to FL which was about a year ago and there is not one spot of rust on it even from driving it in the rain down here. I know there is a huge difference in weather between NY and FL but my point is this car really won't be seeing any type of weather that will rust the exhaust out faster such as rain or snow. So is it REALLY necessary to get the coating with the headers? Will it really serve a purpose besides reducing the rust rate?

 

Headers will almost always rust if uncoated.

I would get magnaflow cats. They carry a new metallic line that flows extremely well and you will probably see little difference. I would put them right after the longtube collectors in a custom y-pipe.

The 3" cats flow about ~570 cfm which is enough for about 260 hp before you see any significant power loss. Double that is 520 (for 2 cats, one on each header)... so that should be plenty.

The magnaflow part # is 59959 for the 3" versions. The only place I really know to get them is eBay. You can also try froogle (summit is backordered).

 

The coating will not only add some more power, but it will also help to maintain some value to your headers if you ever decide to sell them. I had a pair of the 3" Pypes mini-cats welded into my y-pipe. The passenger side is very forgiving, you can weld just about any length cat in there. The drivers side however, is very tricky as you have the fuel lines, brakes lines, and torque arm in the way. That is where the mini-cat proved beneficial as it snugged right in there.

 

I also forgot to ask. Does the stock single cat on the 93-95 have that fitting on the side of it? My girlfriends 91 camaro had it and I wasn't sure if the single cat lt1s had it. I think it's for the AIR system but i'm not sure. Either way, do single cat lt1s have it?

 

Nope, the AIR system is built into the headers, not the cat.

BTW... those magnaflow cats are tiny and run about 115 each. So they wont kill your wallet.

 

Thanks. I'll probably go with the magnaflow as long as they will allow me to pass emissions.

 

I have a couple more questions. I was searching around to find out about the exact gains that LT's and an ORY will give you and the opinions seem to vary greatly. Some say it won't do much for a near stock motor and to spend cash elsewhere and others say it made them 20-25 rwhp and dropped them .5 in the 1/4 mile and is well worth the time and cash. The mods I currently have are a moroso CAI, edelbrock cat-back, TB bypass, and a hypercrap power programmer. My main question is will I REALLY notice the gains? What rwhp gain can I expect? Approximately what should I expect to run in the 1/4 mile? BTW unfortunately I have an A4.

 

You will see a difference. The stock log manifolds are pretty crummy and the long tubes really open it up and allow for better resonance tuning in the exhaust.

As far as gains... you should see 15-20, maybe more RWHP. Especially combined with a good catback and good high flow cats.

A bolt on LT1 should be mid/low 13s. With some sticky tires, you might take home an 12 sec slip.