F.I.T. #20 Dyno'd.....?

[Seneca]

Alright I've got some questions. I had my car Dyno'd today I dont have my scanner hooked up so i cant show the graft. My car made 438 HP at 5800 rpms. The shop said it was running out of fuel from 5000 to 6000. And recommended the fallowing before the finall tune..

60LB high Impedance Injectors,
Boost-A-Pump
Mafia Harness Sensor


Does this seem right? Any input is needed. Thanks Guys!. Seneca

[HwyCruiser]

What size pulley / how much boost are you running? The stuff you got should be fine for a 3.70" pulley / 10 psi but the headers might be making it borderline. I made 465hp at 6200 rpm with a 3.70" pulley and Cobra manifolds and still had plenty of injectors / pump and MAF but was told it would be getting close to maxing out on a cold day. I'm running a 3.80" pulley and who knows what hp now though.

[MarauderTJA]

Like JD stated, need to know what pulley you are using and the boost. I ran a 3.60 pulley making 12 lbs boost and had to upgrade to 60 lb injectors, a Mafia MAF extender and dual Cobra fuel pumps. And then a proper tune to put it all together. I do not care for BAP on our applications. The hot set up is GT 40 pumps for more fuel. That is the way I would go first, prior to injectors etc and see how that works out for you. They should give you plenty of fuel. My above application made 475 RWHP. Your numbers are still very good.

[Seneca]

What size pulley / how much boost are you running? The stuff you got should be fine for a 3.70" pulley / 10 psi but the headers might be making it borderline. I made 465hp at 6200 rpm with a 3.70" pulley and Cobra manifolds and still had plenty of injectors / pump and MAF but was told it would be getting close to maxing out on a cold day. I'm running a 3.80" pulley and who knows what hp now though.


I've got a stock procharger setup. I think it's the 3.80 pulley 8 pounds of boost.
The Tuner told me that he could tune it as it was but it would be border line and come fall with cooler temps A/F would be lean, He said the 42lb injectors were running 98% of their max load at 438hp Does this sound like he's in the right ball park?
P.S. He did tune another procharged MM for this board again it was a stock setup with headers to stock exhaust. I believe he got 410 hp from that car he told me it was my full exhaust that's making it starve for fuel.
Thanks Seneca

[HwyCruiser]

It's a tough call but I'd believe that your probably marginal on good air. I'd go with the GT pump vs. a BAP too, but at this point you're going to have to let your tuner do what he needs to do to square you away - lean isn't good. I'm surprised the SW headers had that much effect though. Did you go with a full 3" exhaust? You might actually have the stock 3.70" pulley but the exhaust is causing the reduction in boost.

[sailsmen]

I would look elsewhere for a cause of the lean condition.

Check the fuel system and the MAF.

[Seneca]

It's a tough call but I'd believe that your probably marginal on good air. I'd go with the GT pump vs. a BAP too, but at this point you're going to have to let your tuner do what he needs to do to square you away - lean isn't good. I'm surprised the SW headers had that much effect though. Did you go with a full 3" exhaust? You might actually have the stock 3.70" pulley but the exhaust is causing the reduction in boost.
Yes i do have the 3" system with high flow cats. Thanks for all the info guys!. I'm going to run the GT pump pass my tuner and see what he says. I'd rather go that route if you guys recommend it. Thanks again, Seneca

[Marauderjack]

Replace your fuel filter and check it!!:confused::cool:

[Haggis]

Where did you go to have it tuned?

[RF Overlord]

Seneca, my understanding is that Greg did a thorough job putting together the F.I.T. kits; you shouldn't need to re-engineer the fuel delivery system to get it to run right. No offence to your tuner intended, but maybe he's trying to get more power from the kit than it was designed to deliver?

Contact Greg and see what he suggests.

[magindat]

+2 on the clean/new fuel filter. That's a common stopper and often overlooked.

[HwyCruiser]

Hey Seneca, did you check the fuel filter? :dunno:

[TooManyFords]

I suspect the fuel filter?

[Zack]

39# injectors are good to 550rwhp.
Your Walbro pump is good to about 520rwhp.
Your MAF is good to about 460-475rwhp.

+ 1,000,000 on the fuel filter.
If your filter has been clogged for a while, it can damage the pump.

You could also have a loose connection in the tank, or ive seen the sock on the pump catch the basket during install and fold over, causing the problem you describe.
Welcome to a blower car!

[Seneca]

I guess I'm going to pull the fuel pump and have a look inside. My fuel filter was changed 2000 miles ago i dont think it's that. heck as cheap as they are i'll change that again too. P.S. Had the car Dyno'd at JPC racing. Thanks again for the info guys. Seneca

[MarauderMark]

Nice numbers Sen :up:

[ctrlraven]

I guess I'm going to pull the fuel pump and have a look inside. My fuel filter was changed 2000 miles ago i dont think it's that. heck as cheap as they are i'll change that again too. P.S. Had the car Dyno'd at JPC racing. Thanks again for the info guys. Seneca

Wish I would of know you were having it done at JPC would of loved to come over and watch it all. Nice numbers btw! :banana: