So I got the truck baselined this morning, (03' 2500 HD 4x4, ProCharged 9psi 6.0L w/35" tires) as I mentioned in my other post it made about 330HP and 360TQ at the wheels. The thing I am concerned about is the A:F ratio, you can see in the graph that it is all over the place, I am ready ditch the FMU, and go with larger injectors and then have the shop tune it. So what size injectors should I get? and do I need a different aux fuel pump or will the inline Procharger supplied pump do the job? What do you think the cost of this will be? I am already about $4500 into the supercharger, if it's gonna be another 2-3K I may just ditch the truck and buy a D-max, I need a reliable tow vehicle, but not quite ready to give up on it yet (I've got a lot of money into it other than the blower, & would lose my a$$ on a trade in)

 

I would definately say that FMU is not working properly.. You would need a set of 8.1 42# marine injectors to ditch it. ASM and Racetronics both sell them for about the same price. You could use different ones but that it the largest direct fit choice you have.

 

Thanks, went to ASM's site and found these 43lb injectors looks like they are what I need, now I am gonna call Fast Chips and see if they will reflash my PCM for the injectors, if so I think I can can get away from the FMU for under 500 bones.

 

You should still get it tuned. Do you have a Fast Chips tune in there now? The reason I am asking is, you should be DBW. Looking at the dyno graph, it looks like some timing is being taken out up top. Just my .02

 

Yes there is a Fast Chip tune now, specific to the procharger, but for stock injectors and FMU, I think a reflash is only the cost of shipping and like $50, I'll have to check. If I'm keeping the truck I want to do gears (4.56's) and remove the speed limiter, so it's gotta go back anyway. DBW?? Help the acronym challenged....

 

drive by wire throttle body. no throttle cable.

yeah that fueling if not right at all. the 42's and some custom programing(probably not mail order) would help a lot. really a procharger in not the best set up for towing. if you want a killer towing set up about anything beats a procharger. turbo, radix, whipple, or for sure a dmax would kill a procharger for towing with that rig. with a procharger you probably are down on horse power till you are over 3000rpm and idealy you wont ever see those rpms while towing.

 

I second that. My truck doesn't really tow any better than stock with my procharger.

 

A Procharger it not made to tow anything. Maybe a Radix or a Whipple. I never used the FMU on mine, but it looks like the problem.

 

[QUOTE=StupidFast]My truck doesn't really tow any better than stock with my procharger.QUOTE]

Really?? Mine is worlds better over stock, I had the lift on for a few months before the charger and it sucked bad towing. The charger made it pull like it did when it was factory, I see 3-4 lbs pretty much any where in the RPM band, but for sure it really wakes up after 3K, these motors are pretty soft below 3K when stock too, so really what I noticed with the charger was the same power curve but just more power throughout it, the TQ curve in the graph is pretty flat. At this point I really wish I had looked into the Radix more, but oh well, it is what it is. So anyway the current plan is the injectors from ASM (43 #'s), lose the the FMU, get some gears 4.56's (Possibly 4.88's the shop is gonna check into that on Monday), then a reflash from Fast Chips to get me on the road and in the ball park & remove the speed limiter so I can get a good 3rd gear run. It will then go back to the Dyno, and if need be fine tuned there. I'm thinkin' after all this the thing may actually even be able to pull a respectable 1/4 mile, I may have to get down to ol' Infineon Raceway for a couple runs, havn't done that in daaaaaays and it's only 15-20 minutes away. Thanks for the responses, I know you guys know your sh*t so please tell me if I'm crazy to keep messin' with this thing.

The way I see it, I would lose about 2 yrs of payments, 5K straight up on trade in value vs loan balance, plus about 10K I got into it (unless I strip it), and on top of all that a Diesel is gonna cost about 10K more than I currently owe. I got quite a bit of room to play with it before I am "losing" money.

DBW - Drive By Wire... got it. TBW (Throttle By Wire) I would have figured out, cuz that was the main reason for the tune in the first place, I was told when I bought the kit that the TBW would freak out if not tuned.

Thanks Guys, sorry for the novel.......

 

The truck's back on the road with the 43lb injectors, no FMU, 4.88's and a new tune. Man what a difference!! I need to get back to the Dyno after I get some miles on the tune and new gears. I had the top speed removed (tested that this morning it's gone) so now I can get a dyno pull through 3rd gear. SOP performance is better but I am attributing that to the gears, however I did notice that my EGT's have dropped by about 200deg. I was a consistant 1200 deg with 1400+ at WOT. Now it is about 1000deg and 1200 at WOT. That alone is telling me the fuel ratio is much better, can't wait to get a few miles on the gears and tune and get back onto the Dyno again.