2002 GT - Goal - 300rwhp N/A

[BD5034]

I am looking to put 300 rwhp down with the 4.6sohc naturally aspirated. I think this is a pretty modest goal, but the part that complicates it is that I want to keep this car as a daily driver, so I don't want to do anything that is going to drastically increase fuel consumption.

I have the 78mm throttle body+plenum from BBK and a BBK chrome cold air kit getting shipped to my house, and will be installing it this week. Those are going to be the first mods to my engine, although I have a borla after-cat already installed. The computer still has the stock tune.

Suggestions on where I could go from here?

[ASUSMC]

In order to get 300 N/A out of a 2 valve you need cam's, longtubes, possibly ported heads, and a tune. The cams are going to hurt your fuel mileage.

[Ruckus46gt]

to be honest your not going to hit your goal unless you throw a set of cams in. I've seen a full bolt on n/a 2v stock heads and stocl cams with a p51 intake throw down almost 295 to the tire, but without cams thats about as close as your going to get. To hit your 300rwhp goal your going to loose fuel mileage. Here is my list of mods that got me 300 on a predator tune...a real tune I would have had more in it(probely 305-310ish area). Car currently has a p51 intake and ported heads and it pulled 328 on a mustang dyno
mods when it pulled basically 300 were
Vt stage 2 cams, Densecharger, C&L plenum, Accufab 75mm t/b, steeda pullies, mac lts, mac prochamber, bassani catback, Fidanza alum flywhee, frpp alum driveshaft, pro motion built t45, steeda triax, frpp 4.30 gears, detriot true track, moser 31 spline axles, arp 3.5" studs, Eibach drag launch kit, Tokico illuminas, hpm mega bite jr lca, steeda hardcore double adj uppers, Pa racing mild steel kmember with stock a arms and spring perches, mm c/c plates

Car ran mid low 12s easily at etown and atco. Sold it a little over a year ago.

the 93 octane compared to 91 will also help a little, but you will see much batter track times with the cams. Cams will make your top end hp curve much diff. I picked up 45rwhp at redline and above with cams

[AZSaleen04]

You can always throw on a Saleen Type IV blower to get that HP over 300. I was able to get 327RWHP on a bad day with the setup.

I do have the entire motor assembly for sale here and I would split up the blower if interested.

[jjmatheson]

N.o.s.

[BD5034]

Ok. Prepare for a long post. Sorry, but I have tons of questions running around in my head and hopefully I can find some answers and get a good plan together.

From what i gather, 300 rwhp is going to be very tough to get without forced induction or nitrous. I'll lower my expectation to 285 rwhp to make it more realistic, since I want to avoid F/I and nitrous (for now - when I don't need it for daily driver duty any longer, I will likely supercharge or nitrous).

So far what I have purchased is the intake plenum/throttle body and cold air kit from BBK, so I was thinking about a new intake manifold next. Do i need a new mass air? Or is that only if I change the fuel delivery system? (what is the P51 intake??)

This car will NOT see track duty, so I'm not worried about the gearing, the shifter, the trans or axels. I want to keep the car as highway friendly as possible since I commute every day in it. I just want to put some more power down for fun factor. I might run it once just for fun to see what it can do.

What is the difference between LT and shorties in terms of HP/TQ gains? My car is very low and scrapes on certain speed bumps already, I'm afraid to put LT's on it. Also, since this is a street car i'll need to do a high flow cat x-pipe... does having the cats hurt much?

[ASUSMC]

I would do an intake change as a last resort. The P-51 is a lot of money and I have heard mixed reviews.

Longtubes will make a difference, they do hang lower and will scrape. Cats don't really make much of a difference at all but if you are going with longtubes not having them is going to make it VERY loud.

[Ruckus46gt]

you should be able to pull 280ish with full bolt ons with stock intake. Since you have a plenum and t/b you'll loose a little money going with a p51. I've seen mixed reviewso n the p51 online, but know 3 n/a 2v's running them and 2 had the intake without cams for a while and there was a very nice gain. If your kmember scrapes then i'd be worry about lt's hitting, I doubt thats the case so lt's are def worth it. Lt's were probely one of the most night and day differences for my car besides cams. I'd focus on full exhaust (lt's not shorties), intake, pullies, plenum, t/b and you should be in the area i stated above. Might hit yoru goal without cats. Your stock maf and fuel system are more then enough for any n/a combo you'll throw at it including heads cams and intake.

[BD5034]

Ok. I'm embarassed. I have no idea what a K member is, but my car definately scrapes on speed bumps and "speed humps" frequently. I don't mean little tiny scrapes either, the car screams bloody murder on the speed bumps near schools and hospitals, even at 5 mph. Will scraping the long tubes affect them in any way besides making them look ugly while the car is on the lift?

Are shorties really THAT much worse?

[AZSaleen04]

Go Supercharged