my engine is starving for fuel!

futureacrowner · Apr 21, 2006

Freddy- I saw your last dyno graph, you have NO BUSINESS even being in this thread.

Few things to straighten out:

You DO NOT need a rising rate fuel pressure regulator. FMU's are lame, and best left to 10yr old mustangs.

Boost is boost, it's nothing but pressure. It doesn't matter if it comes in at 2k rpm or 5k. And how it is produced has nothing to do with the fuel system requirements.

Don't listen to a single thing FF says. His own N/A car is dangerously lean and he had no idea till we poped him on it. IDIOT

BNI- Did you have a fuel pressure gauge on it at all? Is it keeping a steady 45-49psi?

Can you post the maps from the VEC2? I'm curious to see if you have just maxed out the injectors, or if there is a mechanical issue somewhere in there.

First I would talk to who ever did the install/tuning and see if they have any suggestions.

Second- smack the dyno operator. He should have aborted the run when it got to 14:1, let alone 17.

First thing I would suspect is the stock injectors are maxed out, that is if the vec is tuned properly.

DEVILDOG · Apr 21, 2006

b)Stock injectors are good for about 480rwhp, at stock fuel pressure.

Gee...wonder how I got 560 RWHP with A/F at 12 with above.

big-n-italian · Apr 21, 2006

just to clear the air a bit, my tuner is an authorized roe dealer and installer. they are listed on the roe website. we have been in contact with them, and they are offering great advice from what i understand.

<< If I were you the first thing would be to get bigger injectors >>

i believe we all agree that i need bigger fuel injectors. so let me ask this. from what i have read, if i go to bigger injectors, i need high-flow fuel rails for bigger top feed injectors. i have read rumor after rumor that the only bigger side-feed injectors are off of a subaru, or to have my current ones re-sized. subaru injectors would be cheaper, but nobody seems to know the truth behind the subaru rumor, or even better, exactly which subaru injectors work.

does anyone know, or should i just get rails and top feed injectors?

99 R/T 10 · Apr 21, 2006

I have heard that same rumor, and I believe they are made by siemmens(sp).

TOOOFST · Apr 21, 2006

You don't have a Fuel problem.
You have a Tuner Problem.
The good news.
If the plugs are not to blistered or gone your pistons are probably OK.
A good dyno operator/Tuner would never complete a run with an A/F over 14:1
Jack your a genius again,call Larry at Sound Per.or SVS.
Now fix that thing and come on down so I can give you a spanking TOOOFST style.

Chuck 98 RT/10 · Apr 21, 2006

I have heard that same rumor, and I believe they are made by siemmens(sp).

Injectors made by Siemmens? Anybody else find that amusing?

big-n-italian · Apr 21, 2006

<< If the plugs are not to blistered or gone your pistons are probably OK. >>

the plugs we pulled looked fine.

<< A good dyno operator/Tuner would never complete a run with an A/F over 14:1 >>

we never completed a run.

big-n-italian · Apr 21, 2006

<< Injectors made by Siemmens? Anybody else find that amusing? >>

me! :2tu:

Jack B · Apr 21, 2006

To use side feed injectors it is not a drop in. You have to buy fuel rails, the plumbing, an adapter to the oem line and a modification of the throttle. Some make this seeem simple, unless you are very lucky it is not.

Back to the injectors, I have to agree and disagree. I have seen stock injectors put out over 530hp NA. The problem is they go static at about 500 hp or you lose control of the duty cycle, they are always on. Your a/f just goes south too quickly, there is a major problem, an injector issue would show more slowly. On the other hand the problem might be major, but, the fix could be as simple as an adjustment on VEC.

One thing that would cause this is the vec control wire for the injectors. There are two sides to the Vec system, perhaps, one side is broken/loose at the connection point. Once again we are all guessing.

RichieSRT10 · Apr 21, 2006

You're an idiot. It's best that you quit now, while you're behind.

(edit: directed to freddy, in case there was any doubt.)

How can Fast Freddy type his ******** in ******* is beyond me.

Fast Freddy · Apr 21, 2006

lets see i own a supercharged truck, a supercharged boat, a turbocharged car and a turbocharged motorcycle. yea you guys are right........ i dont know anything about boost. what was i thinking? i guess i will just have to put nitrous on my viper and blow all you retards away :nana:

BIG-n-italian > find yourself a good tuner to help you and good luck :2tu:

Makara · Apr 21, 2006

lets see i own a supercharged truck, a supercharged boat, a turbocharged car and a turbocharged motorcycle. yea you guys are right........ i dont know anything about boost. what was i thinking? i guess i will just have to put nitrous on my viper and blow all you retards away

BIG-n-italian > find yourself a good tuner to help you and good luck

Post a pic of you riding that motorcycle again. That should shut them up!!

Russ M · Apr 21, 2006

b)Stock injectors are good for about 480rwhp, at stock fuel pressure.

Click to expand...

Gee...wonder how I got 560 RWHP with A/F at 12 with above.

One of several ways,

1) You have fuel pump or a booster pump upgrade.

2) You are using an A/F analyzer that is giving you faulty reading perhaps a tail pipe sniffer.

3) The dyno you are getting your numbers from is lying. I would bet this one is it since dyno's lie alot and I seem to recall that you use the same dyno as another infamous person on this board that makes 100more rwhp than he should be. But I could be wrong on this one, am too lazy to do a search. If I am wrong I appologize.

Its simple math, 29lb injectors are only good for so much at a certain a/f. My fuel map is the one that comes with every AEM unit shiped so I am fairly certain that its not just me.

Jack B · Apr 22, 2006

How about this:

1. For an NA car at 12.8 a/f the BSFC is 2 hp per pound.

2. 29 X 10 = 290 or 580 fwhp.

3. 580 hp X.88 is 510. hp.

On the other hand I saw MOJO's car do 530 NA at approximately 12.9. In his case the injectors were maxed out and we could not change the a/f at peak hp. He did have the voltage booster, so he was operating right at the top pressure of fuel pressure regulator. That 2-3 psi difference would difference would translate into approximately 5% more volume at the injectors.

In the stock mode our fuel pressure goes down to about 50-51 psi at 500 hp, with the booster it stays at about 53-54, I have been logging the fuel presure for about three years.

Alan has a good case on the injector capacity, one thing I will debate is that the dyno will read rich. This would have to be a bad sensor, a dynojet operating perfect reads lean. It will average about 1/2 point at peak hp and 1 full point at 3000 rpm. My last comments are only after they totally turn off the a/f smoothing and start the graph after the pull starts. For some reason dynojet throws in a lot of averaging (smoothing) even when it is turned off.

Russ M · Apr 22, 2006

Jack with 91 octane being the best available here that is way too lean for wot. We had to do about 12.0-12.2 to 1, or we would get detonation with timing being at no higher than factory levels.

The car in question here seeing 10lb's of boost on pump gas even if its 93 octane would need to be 11.9 or richer to 1 to be safe.

On a side note would you happen to know how much the factory pump can flow if you bump the pressure to say 80-90 psi?

RockStar · Apr 22, 2006

lets see i own a supercharged truck, a supercharged boat, a turbocharged car and a turbocharged motorcycle.

You must be registered for see images

RichieSRT10 · Apr 22, 2006

LMFAO Rockstar I can even imagine Freddy talking like Elmer

JGK95 · Apr 22, 2006

lets see i own a supercharged truck, a supercharged boat, a turbocharged car and a turbocharged motorcycle. yea you guys are right........ i dont know anything about boost. what was i thinking? i guess i will just have to put nitrous on my viper and blow all you retards away

BIG-n-italian > find yourself a good tuner to help you and good luck

Cut Yer Mullet!

:headbang:

DEVILDOG · Apr 22, 2006

b)Stock injectors are good for about 480rwhp, at stock fuel pressure.

Click to expand...

Gee...wonder how I got 560 RWHP with A/F at 12 with above.

Click to expand...

One of several ways,

1) You have fuel pump or a booster pump upgrade.

2) You are using an A/F analyzer that is giving you faulty reading perhaps a tail pipe sniffer.

3) The dyno you are getting your numbers from is lying. I would bet this one is it since dyno's lie alot and I seem to recall that you use the same dyno as another infamous person on this board that makes 100more rwhp than he should be. But I could be wrong on this one, am too lazy to do a search. If I am wrong I appologize.

Its simple math, 29lb injectors are only good for so much at a certain a/f. My fuel map is the one that comes with every AEM unit shiped so I am fairly certain that its not just me.

1. NO.
2. Yeah, I'm sure everything is faulty except what you use.
3. Wrong. Velocity Performance in Dallas.

Anaconda · Apr 22, 2006

I had 523 RWHP with the stock injectors and fuel system at 12:1.

Granted, that was with a hundred shot of nitrous....

Russ M · Apr 23, 2006

I had 523 RWHP with the stock injectors and fuel system at 12:1.

Granted, that was with a hundred shot of nitrous....

Anaconda,

Nitrous systems use their own solynoids to deliver fuel which bypass the injectors. A friend of mine makes 669 with stock injectors/pump and a nitrous system.

Shelby3 · Apr 23, 2006

I had 523 RWHP with the stock injectors and fuel system at 12:1.

Granted, that was with a hundred shot of nitrous....

Click to expand...

Anaconda,

Nitrous systems use their own solynoids to deliver fuel which bypass the injectors. A friend of mine makes 669 with stock injectors/pump and a nitrous system.

Wet nitrous systems do, dry don't.

big-n-italian · Apr 24, 2006

i would like to let everyone know that Paolo spent time on the phone the other day with my tuner, and has been advising us on my car. I wish to publicly thank Paolo for his generosity!

Paolo, thanks again!! :2tu:

you guys are the best!

my engine is starving for fuel!

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