They tested an '07 supercharged HD this month and the results are pretty disappointing. They didnt have any track numbers but they did get it on a dyno at Livernois. Results were 337rwhp and that is not limited by a speed limiter either. Not sure what type of dyno they have but I would guess a dynojet. They didnt mention a torque number but I wouldnt be surprised if they would have trouble getting into the 14's. I have no idea what boost it is pullied for but im sure it can be increased. This is the same setup thats in the Saleen trucks and look what JDM has done with theirs already.

 

Link?

 

I read it in Truckin magazine p.38-39 of this month.

 

Go to your nearest Barnes & Noble and get a Starbucks and find the magazine and read it...

 

I would have to see it to believe what they say. JDM only posts in the 2004+ section when they are trying to see somthing to us. They are salesmen afterall. Where was the proof to back up anything mentioned in thier Saleen posts?

I hope, truthfully, that they show up and proove me wrong. It won't happen though.

 

That is a little disappointing. 113hp lost from the crank to the wheels. I think they are supposed to have 450hp at the crank. I have seen losses of power in the new 5.4's with autos to be up to 26%. 113 still seems to be alot, but it is right around 25% power loss. To be expected with newer autos that are stock.

 

yeah i heard it was loosing a lot of power to the wheels, is this because of the trans. or is it cause we have such a heavy damn truck

 

Probably slap on some lighter wheel/tire combo and that reading will go up some.

Although this is a totally different case, but when I was working at a speed shop, our shop car on the dyno with slicks would show 50rwhp LESS then if it had normal radial tires on.

I'm sure on that big ol Harley if you took those huge cast rear wheels off. Put on some some nice 1 piece billet 18" wheels with some 30" tires the hp reading would jump greatly. Every 1 lb reduction in rotating mass is equivalent to an approximately 8 lb reduction in static weight. With lighter weight wheels, you will benefit from increased fuel savings, quicker braking, improved tire wear and better acceleration. Switching over to lightweight 18's or even 20's I can guarantee losing at least 20lbs per wheel. That is equivalent of losing 320lbs(on the back two wheels), or .32 in the quarter mile, or 32rwhp!

Which in theory would bring the rwhp rating of the Harley to 370 rwhp or a 18% drive-train loss!

So, just by switching out to a quality light weight billet wheels on these Harley trucks, can in Theory drop over .64 seconds in the quarter mile!

This is why you guys with the lifts and big wheel/tire combo's get horrible gas mileage. Those big ol tires and wheels ad ATLEAST 30lbs per wheel I would imagine. 30x4=120lbs 120lbs*8=960lbs It's effecting performance like you were carrying half a ton of cargo in bed!

 

I know what your saying and I completely agree but I had 40 more hp then they did and with a less-efficient roots blower and 24's. I guess I can see alot of factors contributing to the low numbers but I guess it was just kind of disappointing to see essentially what was stock 2nd gen Lightning numbers with a MUCH heavier truck.

 

FATHERFORD if you're numbers are right. I must of got one hell of a motor from the factory!

 

Like I said it's all theroy.

It is a fact though that lighter wheels and tires will GREATLY improve times at the track. You guys with these massive 4x4's with 35's + were to put on a light weight set of 30" diameter tires and wheels, your truck would feel like a rocket ship! Granted the gearing reduction from the reduced tire size would be a factor, the weight loss would probally still be the largest factor of the speed increase.

 

Ain't that the truth!