[rel3rd]

In the past, I've had a few Mustangs that I wound up converting from the stock SPEED DENSITY setup to a MASS AIRFLOW setup. I am 99% sure that along with adding the 4 wires for the mass air meter's sensor connection, I also had to switch a few wires around in the harness. If I did a MASS AIR to SPEED DENSITY conversion, wouldn't I also have to swap these wires around???

Reason for asking, in my quest for stock engine 12's, I tried the MAF to SD swap, but all I did was unplug the maf meter and remove it from the intake tract, and also hooked vacuum to the BAP sensor, which made it into a MAP sensor...The car never seemed to run right and according to my track numbers, I was right...I'm thinking that either the wires had something to do with it, or the fact that supposedly the SD cars run leaner than their mass air counterparts, and the car was maybe just TOO LEAN to make more power. Unfortunately, I didn't have a way to adjust fuel pressure manually for the WOT dragstrip runs, so I basically got pissed and swapped it back to mass air....

I "thought" the wires that were switched around were just something to do with the EGR, but I am not positive...it's been a while since I've done a mass air conversion...

Could either theory I have, be the cause of the car not gaining the power everyone thought it would gain?
Any insight is greatly appreciated...

BTW, Engine is 100% stock, which was why I even considered trying to run speed density. And possibly of importance, the car seemed to have a very definitive dead spot between gear shifts at WOT...like a lean stumble you'd get in an old 4 barrel car...

 

[Ronbuell]

To go to MAF from SD, according to what I've read, this is the method:
Thermactor: wire at pin 51 goes into location at pin 38
Wire at pin 11 goes inot location at pin 32. Reverse those 2 to go back to stock.

MAF leads: power + splice to #37
Ground - splice to #40 or #60
MAF Signal - to #9
MAF Signal + to #50

Unplug the MAF with the reversal of the two thermactor pins should get back to stock.

 

[1 Bad 88 GT]

What's your current setup and how close are you?

 

[1 Bad 88 GT]

BTW a T5 swap will drop a 1/2 sec off your ET.

 

[rel3rd]

On 2006-03-20 19:23, 1 Bad 88 GT wrote:
What's your current setup and how close are you?

Engine is bone stock still, from throttle body to oil pan to factory headers...Car went [email protected] w/1.97 sixty foot, with stock AOD, stock torque converter, 373 gears, Weld Draglites w/drag radials, aluminum underdrive pullies, BBK CAI, off road h pipe, Magnaflow catback...weighed in at 3400# even with me in it.

Over the Winter, I swapped to 5 speed, aluminum driveshaft, BBK X pipe, electric fan, Speed Density, battery in trunk, Strange adjustable shocks and struts, welded in subframe connectors, adjustable rear control arms, and removed 140# total for a car w/driver weight of 3260#...

I went a week and a half ago and was so intent on trying to launch the car off the rev limiter I did nothing but spin the drag radials entirely through first gear both runs...

lol...Car also felt dead top end, so I swapped back to mass air until I can get my adjustable fuel pressure regulator on...Power immediately came back, which is why I asked the question above...I'm hoping the car was just too lean to make power. Car only went [email protected] and [email protected], so I beleive even with the lack of power with the speed density setup, if I had traction, I'd see 12's, or very close to it...but a 2.0 and 2.1 sixty foot aren't going to cut it...obviously.

Next trip to the track I'll have my other pair of 15x8 Draglites on the car along with the Hoosier Quick Time Pros and the car will either HOOK & GO, or......BREAK & TOW, lol...

So far I haven't found a definitive answer anywhere. I know the Factory Stock NMRA guys like running Speed Density, so I even asked over on the NMRA board, but no sure answer as of yet. If I wasn't so intent on running the number with a totally stock engine, I'd just swap on the regulator and see what happens...I just really wanted to do it without swapping anything but spark plugs and oil filter...

 

[SawBones25]

Even swapping pins around, wouldn't your computer be all confused without the MAF?

Do you still have the A9P in there?

 

[rel3rd]

No...I used the DA1 speed density pcm...A few well known Factory Stock guys said all I had to do was run a vacuum hose to BAP sensor (making it a MAP sensor), and unplug maf meter...

I've since given up on the whole experiment as the car runs great with mass air, so I may have had a bad speed density pcm or something?

I've also swapped in a much better breathing engine in the form of a Canfield headed 306 with a Holley Systemax II intake and a STOCK camshaft...went [email protected] first time to track, and made 280rwhp/322rwtq on a Dynojet sae corrected...

_________________
1989 Mustang LX Coupe w/T-5 swap & bolt-ons
Shooting for 12's w/E7's, stock cam & intakes

<font size=-1>[ This Message was edited by: rel3rd on 5/20/06 5:41am ]</font>

 

[Ronbuell]

That's pretty stout. Sounds like a nice car.

 

[rel3rd]

Thanks...actually numbers above were with a self ported Cobra intake, and ET's were with 373 gears. In the last week, I've swapped in some 410's and swapped on the Holley Systemax intake...Hoping for 11's naturally aspirated...