i have a 03 gt with bbk shorty headers, bbk chrome cold air intake ,x pipe , no converters, and a slp loudmouth catback, and a gear.i didnt do these mods i bought it this way. the car seems slow to me, i had a 04 gt all stock except a flowmaster catback, k&n cold air intaks and nittos it went a 8.90 in the 1/8 at 81 mph. my 03 i feel couldnt run a 9.20. i think it lost all of its tq with the cats gone and to free flowing exhaust. any suggestion?

 

Is the car properly tuned?

 

dont know if it has been tuned or not. i bought it at a dealership.

 

What gear was your old car, with driver error both these cars should be the same, catless exhaust and a CAI isn't gonna make much difference power wise.

 

From what i've heard it might be possible that you're loosing a bit of power and torque (especially in the low/mid range) with a full catless exhaust and no tune. Although i can't say that personally since mine was tuned only after a cat back, cai, and gears.

 

Check to see if you have the right MAF in it. I bought an 01 GT a few months ago and the car has similar mods to yours but ran like crap. Turned out someone installed a 90mm Lightning MAF without a tune. I put a stock MAF in it and it drove 100 times better.

 

although the shorty headers flow a tad more than stock, the travel is about the same length, so they should run fine on a stock tune. catless without a tune won't make you slower. you'll throw a code, but you should still gain a little hp/tq.

 

my cobalt ss would destory my mustang,
it put down 322 hp at the wheels. my mustang feels like 200 whp. something just aint right

 

well, honestly, you're probably pushing around 220-230rwhp , so you're not far off. the thing that concerns me though is you said it has gears, but you didnt specify what ratio. if its 4.10s and you dont feel the acceleration, then something is wrong

 

im not sure yet on what gears are in the car . i would say between 3.55 to 4.10.the car just dont pull hard like it should. i know the catless x pipe and the loudmouth catback is hurting me, also the chrome hotair intake ( lol ) it gets hot i mean real hot so im going to go with the k &n coldair intake. so my plans are this

1 take off the crappy slp resanators and install some good flowmasters. that should give me some tq back.

2 get rid of the chrome hotair intake and buy a plastic k & n intake that should give me about 20 hp.lol the chrome one is costing me hp.

3 see if the car has been tuned or not.