[blackmustang285]

I have the saleen 475 HP Kit. I felt like my car didn't have the same down low so I had a dyno run done. The A/F was a little lean so some timing was pulled. The stock fuel pump is not working properly, so the car is parked until I can get the GT 500 fuel pump kit. However, I was curious what you think about the graph because I thought that the torque line should be much flatter than it is. It starts very low according to what I thought it should be. Anyways here is the graph at 12.5 A/F.

[beefmobile]

ya man that seems a little low...

and that sheet is when the fuel pump is defective?

[blackmustang285]

Originally Posted by beefmobile ya man that seems a little low... and that sheet is when the fuel pump is defective?

Yes, it is not getting the pressure that it should. I am hoping that once I put in the GT 500 pump that it will be better. I thought the graph should look more like this.


The torque line is much more consistent in that graph with the same mods. Does anyone know if the fuel pump would cause my results? The pump help pressure, just not enough to get A/F down around 11.5

[NastyFX4]

The dyno graph wasn't even done in SAE ...

[Emay]

The other thing to remember is some motors are factory freaks and others never come alive.

Added parameters can sway HP and torq numbers in a big way. Weather and elevation being just two.

Pile in a bad fuel pump and you won't see anything real impressive.

[blackmustang285]

An SAE graph would just cause the overall numbers to be higher or lower depending on conditions at the time of the dyno run right? I am more concerned with the fact that my torque line starts so low. It should start out higher than it does and be fairly flat until it starts to drop off in higher RPMs. I am trying to figure out what could cause this. I am hoping that the fuel pump is the only issue. The temperature at the time was 57 degrees with 9% humidity, 30.30 in-Hg and STD 0.97.

[blackmustang285]

Originally Posted by Emay The other thing to remember is some motors are factory freaks and others never come alive. Added parameters can sway HP and torq numbers in a big way. Weather and elevation being just two. Pile in a bad fuel pump and you won't see anything real impressive.

I am not concerned with the peak numbers. I am worried that maybe there could be more problems because of the messed up torque line. Would the fuel pump cause this? or do you think there could be other issues?

[NastyFX4]

SAE numbers would be more realistic and are generally the industry standard.

The fuel pump duty cycle is probably maxing out from the very beginning if you say it's bad. What size injectors are you running? Get the GT500 fuel pumps and see what happens than.

[blackmustang285]

I am running 39lb injectors. I definately plan on a trip to the tuner once the new pump is in, but until then the car is not going to be driven. I don't wanna risk the fuel pump going to crap while driving.

[NastyFX4]

When you say it's bad, do you mean it's just maxing out? .. or do you mean there is something else wrong with it?

[blackmustang285]

I don't think I ever mentioned it, but this is an automatic. Could the torque converter be going bad to cause the poor torque line?

[blackmustang285]

Originally Posted by NastyStang113 When you say it's bad, do you mean it's just maxing out? .. or do you mean there is something else wrong with it?

It is maxing out. However the tuner said that usually the stock fuel pump is good for these power levels and that it must be a weak factory unit.

[NastyFX4]

Originally Posted by blackmustang285 I don't think I ever mentioned it, but this is an automatic. Could the torque converter be going bad to cause the poor torque line?

How was the dyno pull done? Do you know? Automatics are a little funky to dyno if you don't know what you're doing. I've seen a lot of guys do some odd stuff with them.

Originally Posted by blackmustang285 It is maxing out. However the tuner said that usually the stock fuel pump is good for these power levels and that it must be a weak factory unit.

Correct. The factory fuel pump should be good for 400-450rwhp usually. Who is the tuner? It could very well be a weak factory unit.

[blackmustang285]

The tuner is Fastlane Inc. in Houston. I know the pull was done in 3rd gear. I know 4th is more ideal but would that cause the torque line to look the way it does?

[kenneth]

For the Auto's 4th gear is a must (1to1 ratio)
unless it's a defictive pump you should still be OK with your power level.

I would bet the torque is so low at the start because of operator error.

[kenneth]

Did they tell you the fuel pump was maxed out or did you datalog and see a problem?

[NastyFX4]

Torque value may be off.

[blackmustang285]

Originally Posted by kenneth Did they tell you the fuel pump was maxed out or did you datalog and see a problem?

They said that the fuel pump duty was having to be pushed to high to get proper amount of fuel. They said that I needed to get the GT 500 fuel pump in order to add more timing and get the A/F down to 11.5

[blackmustang285]

Originally Posted by kenneth For the Auto's 4th gear is a must (1to1 ratio) unless it's a defictive pump you should still be OK with your power level. I would bet the torque is so low at the start because of operator error.

Do you think that the graph would look different had the pull been done in 4th gear? and is the pull in third gear what you mean by operator error? Looking at the graph the horsepower side goes up in increments of 50 and the torque side goes up by 25. Is that supposed to be that way?

[07stanggt]

Originally Posted by blackmustang285 An SAE graph would just cause the overall numbers to be higher or lower depending on conditions at the time of the dyno run right? I am more concerned with the fact that my torque line starts so low. It should start out higher than it does and be fairly flat until it starts to drop off in higher RPMs. I am trying to figure out what could cause this. I am hoping that the fuel pump is the only issue. The temperature at the time was 57 degrees with 9% humidity, 30.30 in-Hg and STD 0.97.

Yes you are correct. But most people on here seem to think that if its not sae corrected its somehow automactically high, and automatically less accutrate. THE STD 97 is your correction factor and those are corrected numbers, what that means is that basically your car dyno at %3 higher then what the sheet says. So really it already subtracted 12 hp.


My dynos with SAE correction and STD correction have always been the same number basically, im not sure where the notion that std correction is always higher. SAE could actually read higher like you said. Heck i went from a 374 dyno to a 399 without touching the car, mustang dyno, sae corrected. None of them are the "accurate" dyno so to speak IMO. The good thing about dynojets and std, it always seem to be consistent. Sae corrected on mustang and dynamics dynos, i see huge swings.