Maf Info

[final5-0]

I know this is an old post. We are thinking about using the stock maf for 95 gt with 30 lb injectors using tweecer rt. We have been using a summit calibrated meter but we think it is toast. So for an experiment we want to try the stock meter and see if the car will run with all
given parameters being the same in scalars and injector offset ,etc. Mind you we are running a v-2. So pegging this meter wll probably be a no brainer. However for an experiment and wanting to see if it will run and do low rpm acceleration and fatten up calibration . Grady what do you think since you have done more research on this than others?
Thanks,
Fritz

Holy Cow

This is old stuff

But ... never the less ... still VALID stuff

Fritz ... since this old post was done ... many others have stepped up to the plate
and have surpassed me in knowledge

I've not kept up all that much in the past year or so as I've needed not a lot of
tuning on my little GT

however

I do believe I can give you the basic info you desire

If I understand you correctly ..........

You wanna bolt on the OEM meter
and
NOT change anything in the pcm
yet
Run 30 pound injectors

NO ... that just won't work ... for several reasons

First one that comes to mind is .........

The blower is gonna peg the little meter

Then there is this as well

You got the pcm thinking 19 pound injectors
but
In reality, you're running 30 pound injectors

In round about thinking

Each pulse width is now 1/3 more than it needs to be due to injectors that
are approximately 1/3 in size larger than the pcm thinks it is using

If you go in there and up the inj values accordingly ......

Then all will be good ... EXCEPT ... when you reach 5.0 volts on the meter

Seems like a waste of time since you would peg the meter


Grady

 

[fkloss]

Okay,
here we go.
I installed the stock meter. The engine started right away. We had the surging idle syndrome. I changed the MAF table on the 1st 8 points and leaned it out. It took about 10%. Vola the car idles betterthan ever. It did not stumble at all up to 3000 rpm and than... forget the boost interferes and the MAF is done. So yes it will work since we already programed RT that we have 30 lb injectors.
The whole reason I did this because we have been fighting the evil gremlins for 3 weeks. The engine has been cutting up right around 3k right when boost starts.
I checked everything. Starting with plugs,wires,dizzy,cap and rotor all new now.
Ignition module it is new too. Fuel pump took it out and checked to see if it worked, it is new too. MSD coil is new. The thing we fixed in the meantime,
new headgasket on pax side. The list goes on...
So now we thought heck it has to be the MAF?? Since this is what started this whole mess to begin with. It disconnected itself from the plug or shall we say was not seated correctly and the problem started. Car would stall ,it would not start,etc. So when we realized 3 weeks ago, there is our problem,Plug the plug.
Yeah so I thought, It is fixed but... no it started this nasty cut out at boost.
So just to see maybe it was the SC and we unbolted the belt and same story engine just cuts out right around 3k.. So now I'm thinking fuel pressure hook a gauge to it and drive it under load. Fuel pressure does not go up and stays around 40 psi but will not go higher. I'm thinking possibly a bad fuel regulator?
I run stock pressure 39 psi and bumped it to 41 for now just to see it FP responds and it did. I'm still not sure though if it might not be my problem along with a bad MAF. Anyway long post since this is really making me go crazyy!!! I also checked the injectors and the seem to work good!! Anyway just venting and messing with Tweecer interesting to see that it will work with 30 lb injectors.
Later,
Fritz

 

[final5-0]

Fritz

Lets put a shout out to Mr. Wes

He has a blown combo as well so he will be more help to you

Seems like your fuel pressure should rise as the boost comes on

Still ... 30's and the OEM meter are too small :Word:

Grady

 

[fkloss]

Okay,
problem fixed for now.
After contemplating on all the things I had already gone over and over.
I decided to look at the FPR and it was hooked up wrong, not even close to any vacum signal. I in my ever great Technical wisdom thought the problem was solved?? However test drive results were negatory and dissapointing. I was
actually fixing things but not the main problem. So again I hooked up the code reader and bang 2 new codes popped up 211 and 212. PIP sensor related.
That dang distributor that we replaced from AZ with life time warranty 3 weeks ago was the problem. I could not believe it ,the dizzy we installed thinking newrebuild or whatever was a dud all along and made me curse and #$%@,anyway this had caused all our issues cutting out above 3000rpm.
So in closing, I 'm running stock MAF right now and it idles like a stock out of show room 1995 mustang. I know it is too small with all the modes but it is kewl to know that before you spend bunch of money on new MAF and in conjunction with the Tweecer you can make HCI and blower run but dont get on it until you run a
WB. Anyway we will be buying a PRO-M since I heard only good things or maybe even a lightning maf. I will not buy another summit MAF though until they can provide some more detailed flow numbers etc..
So right now all is well in MAF land and very soon we will get some dyno numbers with this combo.
Fritz
p.s Wes has helped me out with some of the tunning he is a great guy and a very knowledgeable tuner