98MustangSTL

I have a 98 Mustang GT, it's a 5 speed, flowmaster cat back exhaust, and ford racing underdrive pullies. That is all I have done to it now. My goal is to build this car up to 300 hp, while keeping it emission legal. I was just wondering if anyone knew of any ways to do this or what parts I might need to buy to make this happen. The only thing I really don't want to do is install a nitrous kit. Also, I was wondering what is the benefit of having long tube headers over having shorty's, or if there is even one.

XxphantomsnypzxX

if you want 300 hp at the crank, you can alot closer with aftermarket PI heads. Go to steenracing.com they have stage II headswap kit for 1600. Should get you around 270 bhp. Get some cams too, maybe get you to 280-290ish at the crank. Then you can do the common mods, such as tuner, CAI, etc.

Emann0007

Indeed. a PI swap with some mild cams and a full exhaust and intake mods should get you very close. You'll have one hell of a time getting 300RWHP on a NPI GT.

Go for the longtubes, they offer more HP over the shorties which give give you minimal gains at best over the stock Ironcast manifolds. Most shorty headers will net you somewhere between 4-8rwhp, whereas the longtubes should net you 12-20HP. But if you can afford it, just get the basic intake mods, a full exhaust and a SC.

Lucidus

Heads, intake, and cams should put you DAMN close if not over 300 crank for sure.

Emann0007

his 98 GT stock is putting down 215-220HP stock at the CRANK. That's about 190-195RWHP in stock trim. He has a catback kit and pulleys. We'll generously grant him 10rwhp for those mods. That puts him at 200-205RWHP. I doubt that with a full PI swap and even some VT stage 1 cams you will gain 95+RWHP. I think 50-60crank HP is a more reasonable estimate. Add to that a set of longtubes, a midpipe, and a TB/Plenum combo and he might be close to 300crank HP

GTnAZ

just as a quick side note.. i have wondered since i bought my 02 GT.. what is the RWHP on a stock 02 GT.. and then approx. what is the RWHP with a Magnaflow x-pipe w/converters, full magnapack exhaust, and a cone K&N air filter.
Thanks!

03sonicgt

Probably 235 rwhp.

MustangMafia

They dyno about 220-225RWHP stock. With your mods probably about 235-240ish?

Lucidus

I think a good set of CNCd heads and a nice cam would put him close to 300 crank, if not over. Figure 99+ Gts make 260crank with just Ford PI parts. If he where to take stock PI parts of a 99+ he would be making close to 270 with stock parts and raised compression. I think he will be VERY close to 300 if he goes with a nice set of heads.

Idk, maybe I'm wrong.

GTnAZ

thanks guys!
so to get around 300RWHP all i would need to do is a TB/Plenum combo and intake tube and a set of long tubes?