anybody know the Autothority MAF part number?

[Chuck.H]

I'm pretty sure the Autothority uses a common Ford sensor, does anybody know this part number to replace just the sensor part of the MAF?

BTW, I've had this MAF on my car since the late 90's -- this along with the SSI/M&K really wakes the car up IMHO. I had the B&B originally but it didn't hold up very well and had that annoying 2k drone.

Best,
Chuck.H
'89 TurboLookTarga, 334k miles

[ivangene]

Have you ever Dyno'd it to see what the CO% runs?

I have one of these and ran it for a while but have stock on right now.... I mapped my stock curve but the Dyno is expensive here ($170 for 2 pulls) and i would rather not throw too much money at that right now

just curious -

[Chuck.H]

Hi Ed -

No, haven't dyno'd my car in more than 15 years... I do have an LM-1 AFR meter so I can monitor that when I'm making chip changes. I do all my tuning on the street, lets say on closed or non-public roads.

I kept searching the forum and came up with an older Steve Wong post that says something to the tune of 'don't bother, the Autothority used a custom MAF from Pro-M that doesn't exist anymore'.

Chuck.H
'89 TurboLookTarga, 334k miles

[ivangene]

I have the Autothority chip for the MAF

if it wasnt for changing that I would already have put the MAF back in - something unnerving about opening the DME

[175K911]

Yes it was a Pro-M 70mm piece that Autothority used. My old '86 was the development mule for the MAF kit that they sold so somewhat familiar with it.

At the time we'd dyno'd the MAF with my stock exhaust, SSI and factory sport muffler, and 1-5/8 George's headers with modified sport muffler.
When used with the stock exhaust it only made additional power above 5500 rpm.
When used with the SSI's the combination fattened the area under the torque curve in the 3500-5000 range, but lost power over 6500 compared to the stock exhaust.
When used the headers and modified 911R-type muffler, it lost torque in the 2500-4000 range compared to the stock intake, but made roughy 15% more power above 5500 as I recall. And pulled to 7100 without falling off or going lean.

Then we installed a set of C2 cams, 10.3cr pistons and ARP rod bolts. Got all the low end torque back, fattened up the midrange and pulled like a freight train to 7200. Stock intake made less power across the powerband, and was all done at 6500.

So bottom line- the Autothority MAF really made virtually zero additional power with an otherwise stock engine and when used just for street driving. But once any mods were made to the engine, then the MAF became a more sensible addition. I still have mine in the basement- first one produced. It's been collecting dust for 15 years if that tells you anything.

[Lorenfb]

"But once any mods were made to the engine, then the MAF became a more sensible addition"

The benefit of the MAF by itself has never been demonstrated with a dyno,
i.e. the timing tweaks with its chip we're not eliminated. The typical 'sell' of
the MAF mod is to tweak the timing which makes the real change effect.

[Chuck.H]

Hi Ed -

Thanks for the reply, I did see that your car was the 'mule' during my searches. I don't dispute your dyno numbers, but I've got my intake/exhaust and chip tuning all 'dialed-in' with this setup, and for me it's great in this configuration, really fun to row thru the gears, with enough torque to start in second gear and skip gears if you want. Kind of a 'devil you know' thing, not better or worse.

Here I'm just looking for spare parts, as this has now over 250k miles on it and I like to plan ahead.

Made me think of a possible advantage, not sure the original barn-door AFM can survive 250k miles, with that resistor film getting scraped by the wiper arm. Even with no performance gain, I think the heated resistor wire AFM is a better design.

Chuck.H
'89 TurboLookTarga, 334k miles

[Lorenfb]

"Made me think of a possible advantage, not sure the original barn-door AFM can survive 250k miles, with that resistor film getting scraped by the wiper arm. Even with no performance gain, I think the heated resistor wire AFM is a better design."

A common misconception is that the MAF would have a better long term life than the AFM.
Many cars with over 250K still have good AFMs. Once the AFM is maintained with proper
lubrication, it will have a long term life. When it comes to the MAF, just ask the 993
and later Porsche mechanics about the MAF life, i.e. very marginal life and a costly
replacement. The MAF is basically a very delicate measurement instrument.