Getting 90gt Ready For Dyno/tune Shop

[90GTFIVO]

I have a supercharged 5.0 and have finally found what seems to be a very reputable Foxbody dyno/tune shop in Columbus, OH. Talked to the owner today and gave him my list of mods on my 90GT. He recommended I make some changes/upgrades before I bring the car in. As a few on here already hit on, I need to beef up my fuel pump from 190 Lph to 255 Lph and my 24# injectors to 42# or 60# (if price is comparable). This will allow me to do away with the FMU.

I'm new to all this and he mentioned something about 40# based pressure. No idea what this means, can anyone help?

Few other things I picked up on from reading about the V3 SCi:

I currently have a 75mm mass air meter. If I up the injector size, do I need to have the mass air re-calibrated?

How important is it to upgrade my ignition system?

I read where it would be wise to change plugs to 1 heat range colder than stock. I'll probably go ahead and do this since it will be fairly inexpensive.

If you have any suggestions on what injectors to buy and best places to buy them (cost), please let me know. Thanks!

 

[madspeed]

definitely upgrade to a 255 lph high pressure pump that is meant for boost. I would get 60#ers and maf does need to be calibrated for it. Im running an n/a 333 and planning on boosting it. I coyld get away with my 42# injectors, but probably be near max so i will be getting 60's also

 

[madspeed]

i would also recomend getting an ignition upgrade and definitely at least one heat range cooler

 

[madspeed]

dont worry too much about the fuel pressure, your tuner can handle setting it where it needs to be. if he cant, run away

 

[reldla1996]

Mustang stock factory fuel pressure is 39 psi, or a nominal 40 psi. Sometimes it is advantageous to boost fuel pressure so you can use smaller injectors, but it can cause fuel pump issues (higher pressure can result in less volume from many pumps). Size of injectors required depends on how much HP you plan to run. The MA does need calibrated to the fuel injectors, though the tuner can tune around it (though that means you can't drive the car to the tuner shop with the new injectors installed).

 

[90GTFIVO]

To get the MA calibrated for the new injectors, does that require me sending the unit back to the manufacturer and have them do it?

 

[Noobz347]

To get the MA calibrated for the new injectors, does that require me sending the unit back to the manufacturer and have them do it?

No... part of what your tuner will do is to enter the MAF transfer function into your tune. A "calibrated" meter is not required. You can match any meter to any injector or computer if you tune for it.

"calibrated" meters (I use the term sarcastically) are things that someone buys because they're trying to avoid the tuning process.

Oh... and 42lb injectors are capable of supporting more power than either your fuel rails or your engine block.

 

[90GTFIVO]

Oh... and 42lb injectors are capable of supporting more power than either your fuel rails or your engine block.

But there is no harm in using them (or 60lb), right?

Thanks for saving me a step with the MAF!

 

[Noobz347]

But there's no harm in using


But there is no harm in using them (or 60lb), right?

Thanks for saving me a step with the MAF!

The only harm is that you will be way far away from the ideal injector duty cycle of (roughly) 85%. 60lb injectors are large enough to support 500+RWHP on E85.

Of the top of my head, I really can't up with a reason to NOT run 60's (someone else might have something). If you find an amazing deal on a set of 60's then I'd probably go with it. If they're more expensive, well... your engine combo doesn't justify that expense.

 

[90GTFIVO]

60# Siemens Deka injectors (EV1) for $332. I'm almost convinced this is the best price I'm going to find.

 

[90GTFIVO]

No... part of what your tuner will do is to enter the MAF transfer function into your tune. A "calibrated" meter is not required. You can match any meter to any injector or computer if you tune for it.

Thanks Noobz. So since the tuner can take care of that, I guess the only MAF question I have left is, will my 75mm MAF support my setup (6 lbs of boost)?

 

[Noobz347]

Thanks Noobz. So since the tuner can take care of that, I guess the only MAF question I have left is, will my 75mm MAF support my setup (6 lbs of boost)?

It should. 6 lbs of boost on a stock-ish 302, isn't a ton of CFM. If the electronics on the meter are OEM quality and you run out of head room (max out the meter) then you can always install a Diablo Mafia or something of that nature, to bridge the gap.

 

[90GTFIVO]

If the electronics on the meter are OEM quality and you run out of head room (max out the meter) then you can always install a Diablo Mafia or something of that nature, to bridge the gap.

Maxing out the meter is the same thing as "pegging" I'm assuming. Is there damage that can be done if the meter pegs or will it just be confirmation that I a) need a larger MAF or b) need the Diablo to bridge gap.

I've read through a couple threads where guys were saying they use a 90mm MAF for their boosted setup. I'm assuming they're running a lot more boost than I will, which is why they made the upgrade. Reading through descriptions/specs for the 75mm MAF tends to sound it was made for a cold air 24# setup.

It should. 6 lbs of boost on a stock-ish 302

I'm not sure where the line is before you're no longer sotck-ish. I'll be running 60# injectors with the 6 lbs of boost, a cobra upper/lower intake, cobra roller rockers, 70mm TB, TFS twisted wedge alum heads, etc.

 

[Noobz347]

Maxing out the meter is the same thing as "pegging" I'm assuming.

True

Is there damage that can be done if the meter pegs or will it just be confirmation that I a) need a larger MAF or b) need the Diablo to bridge gap.

I've read through a couple threads where guys were saying they use a 90mm MAF for their boosted setup. I'm assuming they're running a lot more boost than I will, which is why they made the upgrade. Reading through descriptions/specs for the 75mm MAF tends to sound it was made for a cold air 24# setup.

No, you can't damage the unit by flowing more air through it than it can measure. It just lacks the capacity to vary the voltage any further once it's pegged.

Lots of people use the LMAF. It flows a pretty decent volume of air and the resolution is pretty damned good so it offers great drivability in low speed situations.

 

[f8tlfiveo]

if you are getting it tuned you could do what i did. use a 3.5" diameter pipe and put a stock 05 mustang sensor in it. i bought a bung and welded it on the tube so its legit. much cheaper than buying another maf. i got the tube on ebay for 15$ maf sensor on ebay for 14$ bung was 25$ on ebay. and a 90 degree 3.5" intake coupler for 15$... about 70$... then when you max out the stock sensor you can replace with a high performance one and keep the same tube. my tuner told me the 05 sensor is good for 350-375 hp. now that i think about it your setup will prob be over that.. o well, information for someone else then. im putting money on your 75mm maf pegging. i pegged my 70 mm one with gt40 p heads and exploder intake

 

[reldla1996]

I think a 75mm can would fine with 6# of boost and a reasonably stock motor (as Noobz stated). Since you have TF heads, and especially if you have headers and such, 75mm is on the small side. Your tuner can tell you if the MA pegs during the tuning session. Will the MA meter be located before or after the s/c? If the MA is located before the s/c, smaller sizes reduce power and boost (and I would go bigger). If it's after the s/c, it won't impact either as much, and the only concern is pegging. The only negative to using oversized injectors is that sometimes you lose some idle quality because the duty cycle becomes so short at idle.

 

[90GTFIVO]

Lots of people use the LMAF. It flows a pretty decent volume of air and the resolution is pretty damned good so it offers great drivability in low speed situations.

LMAF? Do you mean Larger MAF, as in the 90mm I was talking about?

As for the Diablo MAFia, will this allow me to calibrate my 75mm to compensate for the much larger injectors, which will keep it from pegging? That would then only leave me with the possible problem of not enough air flow for the supercharger, since my meter is before the supercharger. I'm assuming the only issue with that would be I would not get peak performance out of my supercharger, but I could live with that for awhile and save me from having to drop more money on a new MAF.

 

[Noobz347]

LMAF? Do you mean Larger MAF, as in the 90mm I was talking about?

As for the Diablo MAFia, will this allow me to calibrate my 75mm to compensate for the much larger injectors, which will keep it from pegging? That would then only leave me with the possible problem of not enough air flow for the supercharger, since my meter is before the supercharger. I'm assuming the only issue with that would be I would not get peak performance out of my supercharger, but I could live with that for awhile and save me from having to drop more money on a new MAF.

LMAF = Lightning Mass Air Flow sensor

The Mafia does not allow you to tune for X size injectors. What it does is broaden range of the sensor so that the feedback given in (for example) 5 volts at 500 CFM where the meter would normally have given the same 5 volts at 400 CFM.

That's what it means to "peg" a mass air meter. An OEM meter is designed to top out at X CFM. They design them that way in order to provide maximum resolution for the entire CFM range of the intended motor. By installing something like the Mafia, you stretch that voltage range. Instead of 0-5 volts for 0 to 400 CFM, it is stretched, 0-5 volts over 500 CFM. The down side is that small changed in air are not as accurately measured as they were before. The GOOD news is that OEM sensors have are well built and can stand to lose a little resolution without effecting drivability.

 

[90GTFIVO]

What it does is broaden range of the sensor so that the feedback given in (for example) 5 volts at 500 CFM where the meter would normally have given the same 5 volts at 400 CFM.

Is the Diablo a permanent install, where I'd need to mount it somewhere under the hood or is it a flash type application? Either is fine b/c it's the most cost efficient option, so long as I do not have to cut into wires (which I'm not big on doing).

Has anyone on here used one of these devices? If so, what's your opinion on them?

 

[Noobz347]

Plug the Mafia into your MAF harness then plug your MAF into the other side of it.

I've used one before... it does what it's intended to do.