Cjaiceman

Hey all, I have a question about how much power the stock input shaft on a 47RE can handle? I have a 2002 Dodge 2500 with the 47RE and some toys on it. I don't haul any trailers, but it does have power.

I have an Edge COMP, modified waste gate that allows the stock turbo to push 29PSI at WOT, billet Torque Converter, New stronger flex plate, AFE stage 2 intake and 4" open exhaust. I have 33" tires on the truck with 4.10 gear ratio, and on the Dyno it pushed 248rwhp. The guy I work with on the truck stated that I need more fuel, but I don't know how much more power I can get out of the 47RE without hurting it. The truck just hit 62,000 miles yesterday.

Also, I know with the stock 30" tires I could figure a 19-20% loss through the drive line to get the engine hp, but with the 33" how high do I need to figure to get the engine hp? Thanks

Link to dyno run video:
http://youtube.com/watch?v=hSUrVArphIE&fmt=6

http://youtube.com/watch?v=zwWH_Uk0aBg&fmt=6

My friend said the sputtering is due to a lack of fuel, he recommended a FASS fuel system with some larger injectors and that should clear up the issue. He explained it to me as the Edge COMP is putting almost too much demand on the fuel system, and the fuel system can't deliver that much fuel, so the engine is not getting as much as it should. A larger fuel system and injectors would clear that up.

hink

I'm no dyno expert, and I mean NO disrespect, but those HP #'s seem a little lame for your mods. I would think that the Comp would at least put you close to 300hp.

JPR Ram

I agree with you, but as he stated, he is lacking in the fuel department. Maybe those HP numbers reflect that?

dieselrob

Put a fuel pressure gauge on it asap and see how it read. I bet you lift pump is shot. Hopefully you can save your vp from harm, and get a fuel pump setup on there quickly.

Cjaiceman

Cool down a bit dieselrob

I should state that this truck is not driven daily. Its driven MAYBE 50 miles a week, one or two days. I have a company car I drive on the weekdays. Also, the VP44 was replaced at 32,000 miles due to it had already failed. I am in the market to get a real fuel pump on the truck, which is why I am here, but I wanted to make sure that the inputshaft on the trans will not snap if I add 30-60 more HP.

JPR Ram

Your stock input shaft should be fine as you climb up to and maybe a little over 300hp. But keep in mind, "boosted" launch's, "power braking" and sled pulls will put more strain on that input shaft at those HP numbers. If you're easy on the throttle at take off's, it'll ok for now.

As for dieselrob's reply, he's just trying to help you. We've all seen more then enough VP-44 failures due to low fuel pressures. He's just trying to save you in the long run.

Cjaiceman

I know, and I am thankful for it. I sometimes do a boosted launch in 4wd, but not a lot.

If we take the 248rwhp, and times it by roughly 22% to account for drive line loss, I get about 302 engine hp. Considering the factory was 235hp, and I am short in the fuel department, I would say I need more fuel. How much power could I get out of a larger fuel system, with say.... some stage 2 injectors? If I do that should I also get a shaft done, or just run with that for a while?

hink

Wouldn't the Comp be enuff fuel to reach at least 300hp??
Or by the term "more fuel", do you mean a better lift pump?? Doesn't matter, I just thought those #'s were a little low which could point to a problem elsewhere.

JPR Ram

You're backwards. there is no driveline loss when you measure RWHP. You only factor in the driveline loss when you're talking about flywheel HP. So if your making 248rwhp, that means your truck is making 248 Horsepower at the rear wheels.

Cjaiceman

I meant a better lift pump as mine is original and I don't think its doing enough.

Cjaiceman

I think I am straight on this, rwhp is not the same as flywheel hp. I was talking about 302 as flywheel hp, but 248 is what the wheels are putting to the pavement and making the truck move. although, I could be wrong

JPR Ram

Well, if the Comp HAD the fuel available, yeah, the HP numbers would be more like 300HP. But if the liftpump is weak, there will NOT be enough fuel available. So the result will be low HP numbers.

BigB82789

Is it me or does that truck sound like its popping on the dyno? And they didnt seem to load it up very much. I was waiting for them to lay into it and then they were done??

JPR Ram

I do see where you're going. You're not wrong. I was confused on what you were trying to ask. But as for the driveline loss, I beleive it's only about 15%. But I could be wrong.

hink

That's kinda what I was thinkin. As you stated, factory rated at 235, you dynoed 248 with a box that claims 120hp. Now if you only gained 13hp with a fueling box that claims 120hp, and you think that the fuel delivery system is the problem, I would think that the truck would be spittin and sputterin and wouldn't even run right if you only gained 13hp and the fuel system is poor/bad. Get my point??
No denying that a fuel system is in order, but personally, I think you have problems elsewhere too. A wire tap issue maybe??
Anyway, if you put on an aftermarket fuel system, I agree with JPR Ram, as long as you don't abuse it insanely, you should be fine on the stock input.