Tuning Problems.

[black_nightmare]

I have a 2001 Mustang GT that I recently installed a Procharger P1sc Stage 2 kit on. I am having problems with the tune.

Specs:
Procharger P1SC w/ 10 lbs pulley and 3 core intercooler.
Stock MAF w/ MAFia set on 3.
NGK TR-6 plugs
focus fuel pump
KB Boost-A-Pump
42# injectors
Accufab intake plenum w/ 75mm throttle body.
Magnaflow x-pipe and Magnaflow cat-back
3:73 gears.

The car drives great, but will not put down the power I want. The latest dyno only showed 351 rwhp & 361 rwtq. According to my boost gauge, the car is achieving 11 psi of boost at 6000 RPM.



I data logged the run cooresponding to the blue lines and found

1) According to the my Predator, the MAF_V hits 4.9 volts at 4529 RPM. However, it does not stay that high for long and when viewed in Diablosport's CMR_dat software, it only reaches 848 counts at 4529 RPM and 944 counts at 6000 RPM.

2) The spark advance gets to a maximum of 16.5 degrees at 5700 RPM.

3) The load reading gets to 1.41 at 5700 RPM.


Can anyone give me some answers on why this car is not achieving the power it should be? The tuner claims that this tune made 390 rwhp & 417 rwtq on a similarly equipped 2003 GT. Does the load reading seem a bit low given the modifications and the level of boost the car is making? Is the MAF pegged? What should I expect to see for spark advance?

[Scothew]

I would defintely think the MAF is a problem, but I am not familiar with the MAFia enough to know its limitations or uses. Usually, a lightning MAF would be used in a situation like this since it is calibrated for 42# injectors and can flow more air.

[uvbnhad]

I'll agree with the MAF being the problem. With your AFR you are apparently getting the fuel just not the air to coincide. It's running like a pig pretty much the whole way down the graph.

[Scothew]

Well the a/f ratio is about right for a blower car I think. I just think the car can't breathe and can't adjust for the proper amount of air due to running out of MAF.

[DSkeet]

Hmmm, hopefully I won't have any problems when my D1 goes on... Are you worried about running the 10 lb pulley on stock internals?

[black_nightmare]

Someone else told me that despite the voltage almost maxing out , since the counts value stays below 1023 then the MAF probably isn't pegged. My tuner went ahead and sent me a new tune with the MAFia set on 4, but without some definative explaination as to why it is pegging on the number 3 setting, I am a little nervous changing anything on the intake. I don't want to blow it up. Plus I don't know if I need to take the car directly to the dyno again before getting into boost with this new tune.


According to James @ RWTD the calculation to go from counts displayed in the CMR_dat software that I am using to volts is

(Counts * 5) / 1024 = Voltage

(Go here to see his explaination: http://www.modularfords.com/forums/2...a-25368-3.html)

If I use this I end up with 4.14 volts @ 4529 RPM and 4.61 volts @ 6000 RPM.


Why is this different from what the Predator showed and which to I believe?

[boss96]

The maf is ok in your setup since you are using the MAFIA. The maf will continue measuing airflow beyond 5 volts even though the EEC won't recognize it. With the predator you are reading the maf directly and that is why you see it hitting 5 volts. As far as the eec is concerned though, it is seeing less voltage due to the mafia doing it's job.
As far as hp goes, you don't say what your a/f ratio was. Since you have an intercooler you may be able to run a little more timing advance to gain hp but be careful. Finally, maybe it is just the dyno settings that are different than the example you mentioned.
Your load value is typical for a blown car, what your timing and fuel values make the difference.
Bob

[QWKSNKE]

I say richening it up a hair more and add some timing. With the intercooler you should easily be able to run 18-19 degrees at WOT. That should put you in the 380 range

[black_nightmare]

Originally Posted by boss96

The maf is ok in your setup since you are using the MAFIA. The maf will continue measuing airflow beyond 5 volts even though the EEC won't recognize it. With the predator you are reading the maf directly and that is why you see it hitting 5 volts. As far as the eec is concerned though, it is seeing less voltage due to the mafia doing it's job.
As far as hp goes, you don't say what your a/f ratio was. Since you have an intercooler you may be able to run a little more timing advance to gain hp but be careful. Finally, maybe it is just the dyno settings that are different than the example you mentioned.
Your load value is typical for a blown car, what your timing and fuel values make the difference.
Bob

The air/fuel is shown in the dyno curve in my first post. Could you clarify what you mean by the dyno settings? My car was run on a dynojet. I believe that the other car was tuned on a Dynojet 224xLC. I assume you mean the load factor, since that can be changed with the 224xLC for simulating various road conditions? If that is the case, then the tuner has some explaining to do as to why they are quoting horsepower at a loading other than the weight of the car.

I am seeing 16.5 degrees spark advance at 6000 RPM

[QWKSNKE]

Do you have any exhaust mods?

I may have missed it, is this car an auto or 5-speed?