Hp guessing

[PowerSlideGT]

Alright so i will start looking for a new cam, I am buring a k&n cold air induction breather, 350-400 hp is good though i think, how much hp will i have with the e303? What about 24lbs or is 30lbs better?

[Unit 5302]

Egads. Nobody that knows their way around an engine would suggest that a roller cam setup wouldn't offer a great deal more power potential, especially with the popular cam grinds today, than a flat tappet setup. Unless of course danistanggt was confused and thought you meant roller rockers?

The E303 is functional and offers decent peformance but has a reputation for idle surge. It's not the best cam you can buy, but it's not like you're going to pick up much by going away from it with your combination. Interestingly enough, the 280/280 duration danistanggt seems to be recommending is just shy of the E303's 282/282, not that advertised duration means anything whatsoever in this case, anyway. It's even more important to have a roller setup because of the rest of your combination. You should be producing max power in the low 5000s, and the heads you've chosen flow better above .500 lift than the GT-40 Irons or GT-40 P heads. Even so, the SVO heads are not as aggressive as Edelbrock, TFS, AFR or other aftermarket manufacturer products. This would allow you to run a cam with moderate lift while keeping the duration in the low-mid 220s in order to keep the drivability and mid range power by making the most out of the relatively long GT-40 intake runners. Make sure if you go with a higher lift camshaft that the valve springs you have will be okay at the new lift height.

The GT-40 intake is okay. It makes good midrange power, but doesn't have the flow or runner length the highest performing EFI manifolds offer. Do not expect more than 275-285rwhp with the setup you plan on running, and the estimate above of 260-270rwhp based on the stock intake is probably a little high. You'd more likely be in the 240-250rwhp area with the stock intake manifold. The stock 5.0HO intake manifold is the weakest component in the HO's setup and it should be the first thing that gets replaced. Next the heads and last the cam.

Stick with 24lb/hr injectors unless you plan on adding forced induction or nitrous oxide. The stock 19lb/hr injectors would probably be sufficient with your setup assuming you add an AFPR, which you should be doing anyway. Even so, it's better to be safe than sorry. 30lb/hr injectors are massive overkill, and they're likely to cost you fuel efficiency and horsepower due to the very low pressure you'd be running at the rails (around 25psi to maintain stock injector cycle.)

The 75mm T/B is overkill on a N/A car with your specs, and it will probably make the engine a little sluggish on the low end. In addition, the 80mm MAF is unnecessary as you could easily get by with a 73-77mm unit without a problem.

Even with a custom grind cam, I don't expect your combination would make more than 290-300rwhp without head porting and possibly extrude honing the GT-40 intake since it's not an easy intake to port due to the thin wall design.

Just my .02