Myths that were busted today...

[stangliter04]

!st- While I agree you should always check your tune after modding the fuel system... switching from stock Cobra pumps and a BAP to Ford GT pumps and duel FPDMs does not change your tune.

2nd- Royal Purple does not add 10HP (But we all knew that) I just happened to do a RP oil change lastnight so I thought it would be fun to post that.

3rd- Running straight water in the intercooler does nothing over a mix of coolant/water

This was all on the same dyno and my car was sitting for 5 hours before it was pulled. Temps were actually 5degrees cooler today.

Just some FYI from my experience. :beer:

 

[03 Whippled Cobra]

I'm not an expert but I think #1 could be false. I've seen and heard many times that the GT pumps draw a different voltage then the stockers and the tune needs to be updated for this. But I'd like to hear what others think about this one.

 

[03Cobrra]

Wow I thought changing pumps would need a tune also...

 

[TwinTurbo4vGT]

it does...

 

[waltd20012002]

add 1 drop of dawn dishwashing liquid to the straight water mix. it may not change temps any at all but reduces the surface tension of the water thus providing better cooling...

 

[fire_4_effect]

so #2 is false? no way... lol!!! i feel that running such expensive oil is probably better for the ride but we all must admit that it also contains a hint of mind games; we thinking that it is better. IMO the additives help protect and coats better than conventional oil. whatever though, i will probably run mobil 1 until my rides fall apart. lol!

 

[twhitey]

Who checked your tune and a/f? How is your drive ability with the gt pumps and tuned for stock with a bap

 

[LuDamiKE81]

hmmm...

 

[stangliter04]

it does...

oh it does??? Mine must be special...

Mike from Superchips did the tuning at Lamotta performance in Orlando. I thought it would need it too thats why I took the day off and went up there. He pulled the car on the dyno and ran it one time and it made the same power as last time... He looked at the data log/ MAF counts/ fuel duty cycle and it was all about the same except my fuel pump duty cycle it a lot lower now. He had both files side by side and he didn't have to change anything at all.

 

[04sleeper]

He had both files side by side and he didn't have to change anything at all.

He might not have changed anything, but the GT Pumps have a different voltage table than the stockers.

If he left them unchanged then it was tuned incorrect.

Edit: And I agree with the other 2.

 

[stangliter04]

He might not have changed anything, but the GT Pumps have a different voltage table than the stockers.

If he left them unchanged then it was tuned incorrect.

Edit: And I agree with the other 2.

Okay now you have my attention... Is this a big problem? I am scanning my dyno sheet now and i'm going to post it.

Aug Dyno RED

Todays BLUE

 

[04sleeper]

Okay now you have my attention... Is this a big problem? I am scanning my dyno sheet now and i'm going to post it.

I would not say its a "big" problem, just that the fuel pump voltage table is incorrect. Which I suppose could cause issues.

It is a value file that can be easily loded into the tune. I'm not sure why you wouldn't want the correct voltage table for the pumps. :shrug:

 

[Avenger]

Yes, unstable fuel pressure issues for one. The pump voltage is controlled by a PID loop. Having the correct base voltage to start with will reduce the pressure fluctuations because the PID loop won't have to constantly make big corrections to chase the proper pressure drop across the injectors. The fact the you have the same AFR only means the PID is still able to correct the incorrect voltage table that it is working with. You might not see it, doesn't mean it's not happening...

As for #3, my track testing shows otherwise...

 

[stangliter04]

Yes, unstable fuel pressure issues for one. You might not see it, doesn't mean it's not happening...

As for #3, my track testing shows otherwise...

You wouldn't see unstable fuel pressure on a W/B? I just figured something that had to have a retune would show some kind of different results... My A/F is a line over the top of the other line 11.5 straight across. Two different fuel setups same lines. Judging from my dyno sheet would you say my car is unsafe? :shrug:

As for #3 on the dyno it didn't show any different... but the track is where it matters! :rolling:

 

[stangliter04]

Yes, unstable fuel pressure issues for one. The pump voltage is controlled by a PID loop. Having the correct base voltage to start with will reduce the pressure fluctuations because the PID loop won't have to constantly make big corrections to chase the proper pressure drop across the injectors. The fact the you have the same AFR only means the PID is still able to correct the incorrect voltage table that it is working with. You might not see it, doesn't mean it's not happening...

As for #3, my track testing shows otherwise...

I see after you edited your post explaining... Thanks :beer:

 

[Avenger]

I don't think your car is unsafe, I just think you might have issues with the fuel rail pressure sensor later down the road. Your AFR stays the same because the PCM sees (through the FRPS) the fuel pressure fluctuations and adjust injectors pulse widths accordingly. The lower the pressure, the longer the injector must stay open to flow a certain amount of fuel. Opposite is true for higher pressure. There is a lot going on inside a PCM. Injectors pulse widths are constantly calculated to take into accout desired target air fuel, air mass entering the engine, battery voltage, fuel pressure, etc... You're basically making your PCM work "harder" to compensate for the fact you have an incorrect fuel pump voltage table. All these fluctuations might end up puncturing the diaphragm that separates the fuel rail from the manifold boost / vacuum reference on the FRPS, leaving you stranded on the side of the road.

I've always carried a spare one in the glove box while I was still on the returnless fuel system... ;-)

 

[stangliter04]

Okay got ya! Thanks again for the info!

 

[Avenger]

No problem, glad I could help !

 

[04SVT_COBRA]

Wasn't the claimed "10 more hp" with RP done by using more than just motor oil? I think they also used transmission and diff oil as well. Not saying it would have made a difference, but your test would not be valid if that is the case.

 

[Tractionless1]

oh it does??? Mine must be special...

Mike from Superchips did the tuning at Lamotta performance in Orlando. I thought it would need it too thats why I took the day off and went up there. He pulled the car on the dyno and ran it one time and it made the same power as last time... He looked at the data log/ MAF counts/ fuel duty cycle and it was all about the same except my fuel pump duty cycle it a lot lower now. He had both files side by side and he didn't have to change anything at all.

Get it retuned right this time with VMP's Justin also in Orlando.