drill MAF for bigger injs?

[painster]

I have a set of 8, 26# hi-imp injectors I was thinking about putting on my 95 stang, but I cant find a MAF that will work with that size. Someone told me that if you drill out the tube in the MAF where the sensor wires are, it will tell the comp that i have 26#ers. is there any truth to this or not, or is there more to it that just drill the tube bigger? if so, does anyone know the size of drill bit i would need to make the 26# work?
i tried searching but didnt find anything that helps me.

Thanks in advance.

 

[Noobz347]

I've never heard of drilling a meter to try and fool the calibration. I would imagine that if you had a flow bench you could alter the housing so that the transfer function was correct but I doubt that you have one.

Before all of that though....

Why do you need larger injectors?
Why are you trying to run high impedance injectors?
Do have a high impedance driver to run them with?

 

[painster]

I have the set laying around from a different project. I looked on summit and these came up for replacements (part # 150826).
I don't need them as of now, but I'm building in stages working towards boosting (hopefully next year). I'm going to be getting long tube headers, underdrive pulleys, smog delete, and intake manifold and maybe different rocker arms (already have CAI). Also I plan on hooking up my NOS kit.
I'm still in the research stage looking for what I want, and what will work together. Any tips and pointers are welcome. I'm not going to claim I know what I'm doing completely, that's why I am still looking around and asking questions.

 

[Noobz347]

Ok... I'll start with your stated plans:

Throw your 24# High Impedance injectors (if they are actually high imped) in the garbage or sell em on ebay.

Long tube headers.... check They're always a good mod and will scale well with your other plans. Plan on getting a Mini-Starter to go with that if you want the option of ever replacing the starter without having to jack the engine and drop the headers.

Get yourself a wideband O2 meter and an EEC tuner (your choice on brand but make sure it's something that YOU will be able to use).

Go straight for 42# injectors. That way you only have to buy them once. 42# injectors will scale with your mods all way through block splitting HP territory.

I wouldn't waste a whole lot time and effort in an intake until you know what heads you're going to run. Price out a good set of aluminum heads in the 185cc territory. Get some roller rockers, match the new combo to a good intake, and purchase a cam to tie it all together.

To hell with underdrive pulleys. For what? If you take the serpentine belt off completely, you'll gain 6-7 RWHP and likely cause cooling and charging problems. For a 20% under drive? Meh.

If you decide to eventually run NO2 with boost, then you'll need to tune for NO2 and boost. Otherwise... BOOM. You can pick up the remains of your motor after you've come to a complete stop.

 

[painster]

thanks for the input. ill hold off on the underdrive pulleys.

with the 42# injs, would I just need a MAF callibrated for 42# and be good or how exactally would I go about that upgrade? thats how i was told to upgrade to 24# from 19, is it the same for 42#s?

good idea with the wide band, didnt think of that. do u have any sugestions on what EEC tuner to run?

i already have the complete NOS setup, i just need to install it. i will keep the shot low, 50, maybe as high as 75hp. that should be alright without a tune, wont it?

the heads I have been looking at are AFR-1388, and thinking of a set of 1.72 roller rockers with the stock cam (for now).

next stage would be replacing pistons, .030 over, and rods with forged pieces. also, i will be installing them in a mexican block. while i have the engine apart, i would install a new cam and get my heads. along with a few other odds and ends that will come along like motor mounts, oil pump, etc.

any other tips i may be missing? i hope to get the parts early January and work thru the winter and have it ready by spring.

 

[Noobz347]

Folks occasionally get away with installing 42# injectors and a meter calibrated to work with the stock EEC but I wouldn't count it. Regardless of what MAF you run, the EEC has no idea what the minimum and maximum pulse with is for a 42. As a result, you usually end up really rich down low when you adjust FP so that the AFR is correct at WOT.

To do it right, you need MAF meter and the transfer function to go along with it (you would input that transfer function into your tuner).

The wide-band is a MUST if you plan to do all of this yourself. If your running a dry shot, you have no way of knowing if you're even in the ballpark under spray. With a wet system and the recommended jets you're probably in the ball park but you won't know how close you are. The wide band takes all the guess work out.

I don't know what the AFR-1388 is but I can tell you that cam selection is the lynch pin that pulls your combo together. Personally, I would not toss an OEM cam underneath a new set of heads, intake, and MAF. I'd get with someone that really knows cams (i.e. Ed Curtis), fill out his combo sheet, and have him select the cam that will maximize your combo. We're talking about a LOT of lost HP when you run a cam that doesn't suit your build.

Pistons and internals... I'm with ya. Especially if you're planning boost and/or nitrous.

As for a tuner well... There are as many flavors as there are in ice cream. Determine you level of experience and ability to tune. One of the easier tuners I've dealt with is the Anderson Ford Motorsport PMS. You can have your buddy drive the car for you while you read your AFR meter and add or subtract fuel on the fly for your RPM and throttle position, etc. Version 4 will also allow you to input the MAF transfer function and adjust min/max injector pulse width for the size injectors you have. The downside... it's pretty expensive.

The alternative would be to put the mods together and have it chip/dyno tuned. They can always reprogram your chip for your next mod (for a fee +dyno time) but it's the best solution if you have no idea where to even start with digital tuning.

 

[Rick 91GT]

The only meter you could do that so with any success with some tech advice from Lee is a C&L....but I wouldnt advise it. I would use a properly sized Pro-M meter calibrated for your application, especially since you have a SN car, those computers are touchy.

The 1388 is a non emission AFR185 with a 58cc chamber, the 1422 would be the emissons legal version. If you tearing the motor far enough dwon to put heads on the stock cam makes no sense at all, you will not see the gains you could see. If I can help let me know.

 

[revhead347]

The only meter you could do that so with any success with some tech advice from Lee is a C&L....but I wouldnt advise it. I would use a properly sized Pro-M meter calibrated for your application, especially since you have a SN car, those computers are touchy.

The 1388 is a non emission AFR185 with a 58cc chamber, the 1422 would be the emissons legal version. If you tearing the motor far enough dwon to put heads on the stock cam makes no sense at all, you will not see the gains you could see. If I can help let me know.

You can always tell the old farts like me when they used words like Pro-M. Pro-M has been out of business for ages now. The new company is called PMAS. Drilling a MAF is old school as it gets. It's a very inaccurate way of doing things, and has generally been disregarded. We used to do that back in the day when there weren't too many aftermarket MAFs available. If you call PMAS, they can calibrate the meter for whatever you want. I agree with Rick on C&L, I have never had any luck with them. We also used to drill out nitrous jets back in the day, because NOS didn't make jets big enough.

Kurt

 

[Noobz347]

I gotta say though... C&L <appears> to have gotten better over the last year or so. I just inherited a C&L meter (haven't tried it yet) that has a housing that looks like a REAL housing! No sample tubes, gimmicks, or crap... It's just a bare housing that you put your OEM sensor into with a permanent sensor tube that is fixed to the housing. All the years I spent bad mouthing C&L, I'll be sure to post a writeup if this thing ends up being anything near accurate. It actually looks like it could work (but I could be wrong LOL).

 

[Rick 91GT]

Kurt hate to break it to you but PMAS is out of business, Pro-M reopened a few years back...I'm a dealer www.promracing.com

I had a long talk with Lee B owner of C&L with the issues I had seen on the dyno over the years with C&L. I learned alot and have always respected Lee. If the meters are used in the right application with the right parameters they will work properly

 

[painster]

i have a PMAS HPX (6-pin) meter i baught about 4 years ago i never used. but i dont know how to program it or how to use it. would i need a chip or something to plug into the computer or do i need a tuner to reset the whole thing? all i got with it is a cd that shows flow lbs/hr at x.xxx volts.
originally it was going to be used with a 2.3T project i was doing, and going to use a megasquirt. but in the few years since then, i forgot i had it (til revhead brought it up).

 

[Rick 91GT]

Call Sean @ Pro-M he can help you with PMAS meter