True gains of basic mods

I say those values are a little high. Every car is different, but I gained about 30-35hp with: Pullies, T/A, FIPK, Aluminum D/S, 4.10, Long Tubes, O/R X, Mufflers and a stinkin shifter. However my car is a little light with its CM K-Member w/ coilovers, no hood liner, no trunk carpet, no back seats and no spare/jack.
 
Pulleys, T/A, Longtubes, O/R X pipe, 4.10 or 4.30 gears should be the first group of mods.

Then go with a Bullitt intake and some cams.

That setup with using VT's Stage 1 N/A cams should get you at least 280RWHP, and that's without ported heads. If you do the cams, you can forget about the timing adjuster. You'll have to get the idle adjusted, so you might as well retune the whole car while you're at it.
 
40th GT said:
Would one gain about 3-5hp from a Magnaflow catback?

Yeah, that's about right. Unbolting the cat back and leaving just the stock h-pipe only nets 7 or 8 rwhp. The biggest gains are in the h-pipe, but without a good cat back you can't realize all the gains of an aftermarket mid-pipe. So other than for better sound I would save my money and get a mid pipe & catback. Should be good for about 20 rwhp.
 
Jackie Chan said:
i think i'd rather have a little more mph than 100 instead of a 280rwhp dyno sheet

It's a 2003.

The 13.5 @ 100 was BEFORE the u/d pullies & predator. So that was with 262 hp. I suspect I should be in the low 13's with a couple mph more now. You might want to pay attention a little more when you read the posts. Bone stock the car ran [email protected]

The numbers ARE real and are SAE from a superflow dyno. And all runs were done on the same dyno.

The break down was about 35 from the exhaust & cai, 8 from the pullies, and the rest from the diablo tune.

Believe what you want. I have the car, the dyno sheets and the timeslips.
 
mad4mods said:
It's a 2003.

The 13.5 @ 100 was BEFORE the u/d pullies & predator. So that was with 262 hp. I suspect I should be in the low 13's with a couple mph more now. You might want to pay attention a little more when you read the posts. Bone stock the car ran [email protected]

The numbers ARE real and are SAE from a superflow dyno. And all runs were done on the same dyno.

The break down was about 35 from the exhaust & cai, 8 from the pullies, and the rest from the diablo tune.

Believe what you want. I have the car, the dyno sheets and the timeslips.
sorry all i have is timeslips