My buddy wants to run an x-pipe on his 03 cobra. If we run the catted one will you be able to hook up the rear stock 02 sensors and will it keep the check engine light off or will we need to run MIL eiliminators.
An X-pipe will not yield any performance gains. The stock cats flow surprisingly well and from our experience with our blown 99 GT the X-pipe caused us to lose 1 lb/ft of torque and gained 0 horsepower.
That's very interesting...I just read in either MM&FF or 5.0 Mustangs. (can't remember which one) that they tested the stock H-pipe on an '03 and found like 16 psi of back pressure. Odd that offroad pipes didn't make more power on your 99...
I agree with Chris...mostly....I run cats on my car. I don't think cats hurt much in the 400-500 RW (or more) range. I've seen a lot of cars on the dyno set up similar to mine, and I can't tell they consistently make more HP and TQ than my car. Some do and some don't. Even if cats did hurt you 10 HP or so, that's not noticeable or meausrable for hi hp street cars. It sure smells better with less noise also with cats.
I went from stock 6-cat H-pipe to Bassani 2 Cat X-pipe.
Now, if you're going with off-road X-pipe you may gain some. I don't recommend off-road stuff for a number of reasons.
1) It's illegal. If a state trooper wanted to be a jerk you can suffer serious fines for removal of emissions equipment in most states. The offense is Federal and is up to $5,000 per disabled emissions device. This just gives them one more thing to hassle you about.
2) It's environmentally unfriendly. Todays catalytic converters flow extremely well compared to their early 70's couterparts. They are also extremely efficient at what they do.
3) The smell. Personally I get real tired of the raw exhaust smell getting on my clothes, the interior of the car, etc.
Now, to each his own, but personally I'd recommend anything with catalytic converters on it.
I run 1 5/8" Ford shorties, 2 1/2" Basani X with cats, and 2 1/2" Bassani exhaust, I've seen 572 RWHP and 460 RWTQ (uncorrected) on cool day. That corrected to about 550 RW. I have seen a few cars with my approx set up and no cats make a little more, and a few make a little less. That's why I think running cats on the street just doesn't hurt. And if it did hurt a few HP, you won't notice the loss. And...it quieter and smells better. Plus some of the other reasons Chris mentions.
Call Ron Short. 817-798-7667. He offers both the bassani and magnaflow x with or with out cats. He also sells dr.gas offroad x pipes and makes a custom dr. gas x with cats. You will pick up around 10-15rwhp depending if you go with the cats or without. You will need mils if you go without cats, or a chip to turn them off.
I run the Bassani catted x-pipe on my '03. If you run cats you won't need MIL elimiators, as others have stated. I gained 22.7 rwhp / 14.4 rwtq when I put the x-pipe and JBA headers on. You guys can argue whether that gain was in the headers or the x-pipe .
A forum community dedicated to Ford Mustang owners and enthusiasts. Come join the discussion about performance, production numbers, VIN decoders, modifications, troubleshooting, power adders, DIY tutorials, and more!