bad news/ good news

[QWKSNKE]

Went to the dyno today.

Bad news

Pegging the Univer at 5200 rpm and seeing 97% duty cycle on the 42's.


Good news

515rwhp/534 rwtq :banana2:

[94five0]

sick numbers, Lee. :nice:

were yall at Walker? i dropped by round 1 and asked blake if yu were dynoin?

[Wall96cobra]

Hmm that's wierd, I've never heard of anyone pegging a univer. Wonder if you could take care of it with the tweeker? Congrats on the numbers though!!!

[QWKSNKE]

sick numbers, Lee. :nice:

were yall at Walker? i dropped by round 1 and asked blake if yu were dynoin?


yeah. my appointment was at 4. Blake told me you came by but he didn't know that I was on the calendar

[Shorty]

nice numbers Lee. looks like you need some bigger injectors. :nice:

[slvrbullit]

nice numbers man. get those injectors worked out and see what it will do.

[natedawgg94]

:jester: good numbers lee congrats and hope ya get the bugs out :chug:

[EZ SPEED]

Put some 60#'s in it like I have :D

[Wicked]

Nice numbers.
Strange that you are running out of everything, MAF and injector.

What size univer are you using? Is it Jonathan's old one?

Just curious, what is your WOT fuel pressure?

[QWKSNKE]

3.5 univer off a blown 01 cobra.

I would guess I am seeing around 55 psi of fuel press @ WOT

[Wicked]

3.5 univer off a blown 01 cobra.

I would guess I am seeing around 55 psi of fuel press @ WOT

Does your AFPR react to boost? i.e. a lb of fuel pressure per pound of boost.
I think they may all do this. What is your vacuum off fp at idle?

I guess I wouldn't have expected the 42's max out so soon since at 55psi they are basically the same as 50's at 38 psi.

[Craig K.]

what were your old numbers Lee, finally see a big improvement?

So what do you need to do to correct this, through a Holley 1050 dominator on it...
Just kidding, just need bigger injectors?

[NightHawk756]

I've talked to several tuners that have all told me the same about 42's. They'll max out somewhere between 450-500rwhp. That's why I went with 55's. ;)

[QWKSNKE]

I've talked to several tuners that have all told me the same about 42's. They'll max out somewhere between 450-500rwhp. That's why I went with 55's. ;)


Flashbang is right. 42's are only good for about 475-490rwhp at the correct duty cycle.

I am going to 60's later on this summer.

How is a fuell press regulator going to up the pressure after 1 lb of boost. I have never heard of that.

[QWKSNKE]

what were your old numbers Lee, finally see a big improvement?

So what do you need to do to correct this, through a Holley 1050 dominator on it...
Just kidding, just need bigger injectors?


My old #'s were 525/532. I figure that the car will gain another 10-15 rwhp after a few more thousand miles are put on it.

[Italian LX]

How is a fuell press regulator going to up the pressure after 1 lb of boost. I have never heard of that.
The boost pushes against the diaphram and increases pressure similar to how vacuum decreases pressure. The regulator would have to be deigned to work this way and I'm not sure that Kirbins are set up like that.

[Italian LX]

Hmm that's wierd, I've never heard of anyone pegging a univer. Wonder if you could take care of it with the tweeker?
No, there is no way to change the output voltge range of a MAF in the ECU. The only solution would be to have the meter recalibrated.


Btw, this goes back to my arguemnt earlier about not being able to use a MAF calibrated for smaller injectors with larger injectors. ;)

[Wicked]

The boost pushes against the diaphram and increases pressure similar to how vacuum decreases pressure. The regulator would have to be deigned to work this way and I'm not sure that Kirbins are set up like that.

Exactly. I didn't think regular AFPR's worked like this, but my friend's Aeromotive does and so we had to take this into account when tuning. Wasn't sure if yours(Lee's) did as well.

I was merely asking out of curiousity.

[asilver2001gt]

what about a MAF x-tender or would that require you to switch to a draw thru setup

[EZ SPEED]

On the topic of FPR's.....I ran across this information the other day:

Posted by James @ Running with the Devil.com
The Lightnings are return style fuel systems. The rail pressure on them is set to 39psi from the factory, is non-adjustable from the factory, and non adjustable in a tune. On '99 and up Mustangs with the returnless fuel system, you can adjust fuel pressure via the tune, but this is an entirely differently situation, and IMHO one should *never* raise rail pressure above the factory delta, regardless of vehicle (Lightning, Cobra, Mustang GT, etc.). If they are doing this, they are most likely doing it in an attempt to compensate for undersized fuel injectors (i.e. '03-'04 Cobras with the factory 39# injectors running a KB), and shouldn't be running that much power with the factory injectors in the first place, nor even attempting to tune like that.

Lemme further explain for everyone:

The stock fuel pressure regulator is set to increase fuel system pressure by the same amount that boost pressure increases. With this being said, if a system is running say 8#'s of boost, fuel rail pressure will have increased by 8#'s, but only while the system is actually experiencing this additional boost pressure. The reason for this is simple, in order to maintain the same flow rate through the injectors, the pressure across the injector (aka the delta p) must remain the same. So, if intake pressure has increased 8#'s, then fuel system pressure must also increase by 8#'s. i.e. a Lightning at 39#'s of fuel pressure and making 21#'s of total boost, should have a total delta of 60#'s while at 21#'s of boost.

Kevin, your base fuel pressure should be 39psi. You don't even need an adjustable regulator, but having one will not hurt (nor really help). The Lightnings have fuel rails which can handle approx. 800 rwhp from the factory, and you already have 60# injectors and twin 255lph fuel pumps. That's all the fuel system you will ever need to support your combination. If you have any further questions concerning your tune, please ask me directly

[ChipR4cam]

It's got less timing in it doesn't it now, Lee? Please. :D

[Italian LX]

It's got less timing in it doesn't it now, Lee? Please. :D
I believe the total it is commanding is 20.8* at WOT. :nice:

[QWKSNKE]

:yup:

[ChipR4cam]

What was it before? I can't remember exactly.:think:

[QWKSNKE]

it has always been around 20-21

[93Cobra#2771]

No, there is no way to change the output voltge range of a MAF in the ECU. The only solution would be to have the meter recalibrated.


Btw, this goes back to my arguemnt earlier about not being able to use a MAF calibrated for smaller injectors with larger injectors. ;)


As long as the meter is not pegging, that is the route you actually want to take. Gives the meter more resolution during normal driving conditions.

Lee, you do know that the old ProM is up and running and doing recalibrations, right? Same employees, but new company name and new management.

[QWKSNKE]

Lee, you do know that the old ProM is up and running and doing recalibrations, right? Same employees, but new company name and new management.


:yup:

[Italian LX]

As long as the meter is not pegging, that is the route you actually want to take. Gives the meter more resolution during normal driving conditions.
Yeah, I know that, but I seem to remember a little while back some people sying that you could fix a pegging MAF through software. :rolleyes: I'll have to do a search and see if I can find it.

[93Cobra#2771]

:eek:

[Wall96cobra]

I still think something is not right here, univers don't peg this easy. I seen amny people run more hp and boost and still not peg them, why wasn't he pegging it before?

[Italian LX]

I still think something is not right here, univers don't peg this easy. I seen amny people run more hp and boost and still not peg them, why wasn't he pegging it before?
He may have been. I never checked the datalogs before. . . I trying to remember if we even datalogged the pulls for the first motor.

Did we, Lee?

[Wicked]

Yeah, I know that, but I seem to remember a little while back some people sying that you could fix a pegging MAF through software. :rolleyes: I'll have to do a search and see if I can find it.


You can A) peg the MAF(exceed the range where it recognizes increasing airflow)) or B) Peg the MAF input to the ECU(4.99 volts is usually the peg point).

If you are only pegging the MAF itself, you need a bigger MAF. You have exceeded the airlflow the MAF will recognize.

If you are pegging the ECU. You can scale the entire MAF curve down(using a MAFExtender) and then tune the injector slopes and displacement using the scalar that you scaled the MAF by. This brings the scaled MAF voltage back below the 4.99V peg point but since you have scaled the injector slopes and displacement your tune is still the same. The only drawback(although small) is you lose some low-flow resolution in your MAF curve.

Tim at MPH has used the MAFX a lot and made 700rwhp from 90mm LMAFs that usually peg at 500rwhp.

[Disney Lincoln]

Is your meter draw thru?? Are you running it in draw thru or blow thru?? A draw thru meter will peg fairly early if used in blow thru configuration.....

I agree, You should haev not pegged a 3.5" Univer at 500hp. And the 42's should be good to 600 to the tire.

[QWKSNKE]

Is your meter draw thru?? Are you running it in draw thru or blow thru?? A draw thru meter will peg fairly early if used in blow thru configuration.....

I agree, You should haev not pegged a 3.5" Univer at 500hp. And the 42's should be good to 600 to the tire.


Its a blow thru..

Nope, there isn't a tuner or anybody else out there who will recommend 42's on a 500 rwhp supercharged mustang (or lightning). Turbo cars can get away with it though

[Wall96cobra]

I was also thinking the univer could have been calibrated for a drawthru rather than a blowthru because the univers can be calibrated for either but it could be something else. I saw where you can raise the max voltage on the maf from 4.75v to 4.99v with the tweeker, have you done that yet? Did your car go lean when it pegged?

[QWKSNKE]

no. it did not go lean

[Italian LX]

no. it did not go lean
Yeah, that was the weird part. The A/F stayed fine even after the MAF pegged. I even went back through and looked at the datalog and the PW went from 22ms @ the MAF pegging (around 5200rpm) and dropped to 20MS by the end of the pull. The only thing I can think is that the fuel pressure was increasing at the same time due to the regulator. :think:

[93Cobra#2771]

When the MAF pegs, you don't get "instant lean". If it is only barely pegged, the a/f may not change much at all. It is a progression of less air being metered. In other words, when you peg, you don't get any extra fuel added past the max amount of meter air.

And if you have a good safe/rich tune to begin with, you may still be OK and safe in a/f. Make sense?

[Italian LX]

When the MAF pegs, you don't get "instant lean". If it is only barely pegged, the a/f may not change much at all. It is a progression of less air being metered. In other words, when you peg, you don't get any extra fuel added past the max amount of meter air.

And if you have a good safe/rich tune to begin with, you may still be OK and safe in a/f. Make sense?
It makes sense, but the MAF pegs at 5200 and the pull was up to 5700 (if I remember correctly) and during that 500 rpm, the pulse widths actually decreased. I guess it went through the 500 rpm pretty quickly. :shrug:

[93Cobra#2771]

Yep, I say it was quick.

[TheJeanyus]

Little late getting to this, but those are nice numbers. I agree that with some mileage the numbers should come up a little. Not that 10 rwhp is noticeable when you're talking about 520. :metal: