Will An In-Line Fuel Pump Help?

[Jeff Chambers]

Originally Posted by Dark_5.0

I was hoping my stroker would put out over 350RWHP so would you suggest I go with 36# injectors Jeff?

The fuel system analyzer on this site says for 420HP at the flywheel.

24# injectors 63 psi in the safe zone.
30# injectors 40 psi
36# injectors 28 psi over injected

So naturally I was about to buy some 30# injectors.

I know you have seen alot of dyno pulls and I am not doubting what you say. Just trying to better educate myself before I buy more injectors to replace my 24#ers.

I'd go straight to 42# injectors and be done with it. They can be had for less than 36# nowadays and give you the margin to not only be safe, but to grow on down the line. There's plenty of deals out there where you can get the injectors and a 90mm LMAF for less than retail on the 36# injectors alone. Remember, that there's really no such thing as too big of an injector (within reason). When properly tuned, the delivered pulsewidth is only going to be whatever is required to meet the commanded lambda.

[1989GT]

1st run (Base Pull) 326 RWHP/ 311 RWTQ (11.2 A/F) (15* timing)
2nd Run: 346 RWHP/ 320 RWTQ (13.8 A/F) (15* timing)
3rd Run: 353 RWHP/ 319 RWTQ (14.5 A/F) (16* timing)
4th Run (150 Shot) 502 RWHP/ 511 RWTQ (15.2 A/F) (13* timing)

Do you really think the tuner would have pulled fuel if he was seeing the car run lean?

Sure looks like someone pulled fuel out to me My question is if the tuner new the car was running lean and that it was a fuel problem why did he release the car back to the owner in an unsafe condition? Or give some sort of advice as to how to fix the problem, as opposed to having the owner come on here trying to figure out what his problem is? Look Jeff I'm not trying to argue with you, I just posted how I see/understand things and if I'm wrong then by all means help me understand. I have a great deal of respect for you and your opinions.
I had a good friend of mine make 365 rwhp with 30 lb injectors a little while back, combo was a stock lightly ported heads, trick flow intake, stock cam and 1.7rr and a procharger with 8 psi. 40psi base pressure and a 1-1 fuel/boost sensitive regulator. 11.5-12:1 A/F across the board.
Also my point about the fuel pressure is that you can turn it up as high as you want but the computer will shorten the pulse width of the injector to compensate for the pressure increase, because of the commanded A/F ratio, but until the computer takes in all of it readings (o2, MAF etc) the car will run richer, and better in this case until the computer "learns" what is going on. Or atleast that's the way I understand it.

[Jeff Chambers]

[QUOTE=1989GT]1st run (Base Pull) 326 RWHP/ 311 RWTQ (11.2 A/F) (15* timing)
2nd Run: 346 RWHP/ 320 RWTQ (13.8 A/F) (15* timing)
3rd Run: 353 RWHP/ 319 RWTQ (14.5 A/F) (16* timing)
4th Run (150 Shot) 502 RWHP/ 511 RWTQ (15.2 A/F) (13* timing)

Sure looks like its out of pump and injectors to me. That 15.2 with the wet system sure tells me that something is maxed.

Tuned two Porsche cars yesterday heading to the 24 Hours of Daytona. Second car was drifting lean beyond 5200rpm. Replaced the pump with a brand new pump of the same size/type (stock replacement) and the car perked up and continued to make power to 7200rpm. All the MW analyzers in the world can't take in to account all the variables. If this guy is really concerned about the health of his motor, he'd get it back to a professional that can diagnose what's happening.

[Jeff Chambers]

Originally Posted by 1989GT

My question is if the tuner new the car was running lean and that it was a fuel problem why did he release the car back to the owner in an unsafe condition? Or give some sort of advice as to how to fix the problem, as opposed to having the owner come on here trying to figure out what his problem is?

Do you really think the tuner could deny the customer his car because its running lean? Sounds like to me that the dyno shop told Winged that he was out of fuel but HE chose to take the car and figure it out himself. As a shop owner, I know that I can only recommend to the customer. I can't force the customer to do squat. I can't tell you how many times I've had a customer leave the shop with something less than ideal because his buddy has a similar set up or because some internet jockey on the Corral said it was OK. Can't tell you how many times I've seen those same customers hurt their equipment or struggle with less performance than they really have the capability of.

[1989GT]

Sure looks like its out of pump and injectors to me.

So what happened between the 1st and 2nd run? (with the info we have) it looks like the car picked up 20 rwhp and went really lean with no changes. Then with the car running out of fuel the tuner decided to add timing for the 3rd run. Now here's a question for ya, if the car was running out of fuel making 350 at the wheels why would anyone try to spray a 150 shot on it?

[Jeff Chambers]

Good question on the NOS run....only Winged or the tuner could answer that.

[Dark_5.0]

I want to see a dyno graph. First he asked what parts he should buy and a week later hes at the dyno for the second time.

I am sure I am not the only one that thinks this is a little fishy. Especially since a week earlier he also had 24# injectors if you look at his other thread.

I was interested in his results but I am having a hard time finding them credible.

[~The Jester~]

Originally Posted by Dark_5.0

I want to see a dyno graph. First he asked what parts he should buy and a week later hes at the dyno for the second time.

I am sure I am not the only one that thinks this is a little fishy. Especially since a week earlier he also had 24# injectors if you look at his other thread.

I was interested in his results but I am having a hard time finding them credible.

Forgot one of my all time favorite sayings:

"If it walks like a duck, looks like a duck, and flies like a duck, do you really have to wait to hear it quack?"

Someone has some wires crossed, not telling us the whole story, or is just flat out playing games with us.

[Dark_5.0]

Originally Posted by Jeff Chambers

I'd go straight to 42# injectors and be done with it. They can be had for less than 36# nowadays and give you the margin to not only be safe, but to grow on down the line. There's plenty of deals out there where you can get the injectors and a 90mm LMAF for less than retail on the 36# injectors alone. Remember, that there's really no such thing as too big of an injector (within reason). When properly tuned, the delivered pulsewidth is only going to be whatever is required to meet the commanded lambda.

Thanks Jeff,

I have a local guy here where I live that is well known in the modular mustang world that is going to street tune my car so it should be all good.

Is there a plug adapter for the lightning mass air meter. If I remember correctly the plug is shaped differently.

[Jeff Chambers]

mass-air.com has a connector. Motorcraft also has a new style pigtail but I don't have the number handy.