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Completed Project My 98 super charged EX

Use this prefix for completed projects that are not "How to" articles or threads asking for help.
1998 Explorer 4.0 SOHC
Bought it with a melted alternator/wiring harness from a junkyard for $1,000
Fixed it, drove it for two weeks, then I boosted it.
Started with an M90 supercharger kit from
Upgraded to an M112 Lightning supercharger that was a prototype kit.
Next was the M122 off a 2012 GT500
I have reached 20 lbs of boost (with ARP head studs) and a 12.83 in a quarter mile.

1. How it looked when I brought it home.
2.The M90 supercharger installed
3.The GT500 supercharger installed
4.How it looks now
green ex.jpg
Lowered Rear.jpg
Exploder wheelie.jpg

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In 2011 the mustang went to a frequency MAF sensor, I think they might have gone to wideband O2 sensors at the same time.(If anyone reads differently let me know). So no WOT fueling adjustments until at least 2011?
So in other words the vehicle would have to have a wideband O2 sensor from the factory and the WOT adjustments enabled in the tune.
Conventional O2 sensors(narrowband) were only accurate at stoich (14.7 on pure gasoline), the further away from there the less accurate they became.
Naturally aspirated vehicles usually run around 12.5 at wot. I run 11.3 lol. No automatic WOT fueling adjustments for me.

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One more thought,
We are teaching new classes as of last year and it seems all new fords have a wideband O2 sensor for the upstream location and conventional O2 for the downstream.
The downstream usually runs from 0-.9 volts just as in years past but when offline(cold or unplugged) it reads 1.7 volts. They don't say why but I assume there may be a test voltage applied to the signal circuit that makes it read 1.7 volts.

The wideband O2 sensor ford is calling UEGO.
It displays in A/F ratio, Lambda, and current.
Stoich would look like 14.7:1(pure gas), 1 for lambda, and 0uA for current.
A Rich reading would be lower for all pids, example 12.5:1, .850 lambda, and -300uA (negative amps)
A Lean reading would be all higher numbers, 16.3:1, 1.10, 300uA (positive amps)

The above numbers are just examples, the A/F and lambda numbers match meaning 12.5: is really .850 lambda but the current probably doesn't as I am not used to looking at current numbers for O2 sensors on regular basis.

Its awesome that you keep up to date with the latest stuff the manufacturers are doing.
I just wish we all had the cash to buy this new(er) stuff and modify it.

Its a safe bet none of us here would even think seriously about buying an aftermarket ecm like the Dominator for our old trucks. The age of them and money sure stand in the way.

I bought one of the first aftermarket EFI kits Holley made, the "old" 4 barrel CFI unit called Projection. It was four injectors of 60lthr each or 90, I forgot. I never got to use it, sold it when the project went south. But that was about a $900 kit, big deal back in the 90's, but it wouldn't run as well as any OEM 90's or newer EFI.

The early OBDII systems are still very good versus older EFI, but yes the latest EFI are much faster and easier to tune etc. We work with what we have, and do okay generally.

Keep going, we'll keep nudging you to preserve that fast truck for a long time. Now's the time to locate a clean and rust free body donor for you.

From 05-31-2019 Atco Dragway open track rental.


That video is well done as usual, and it embarrassed a vette. I like that you smoked him at the line by over a 1/2 second, so it was only a second difference at the end.

Explorer vs Chevelle


Way to get after ‘em!!!

Explorer vs Honda S2000
From 05-31-2019



Well done, you have that light figured out.:burnout:

Yea, now that you mention it I haven't red lighted in a while. LOL
I am anxiously waiting for September to go racing again. I cant stand this high heat and humidity stuff!

Hmm, that sounds like my problem of the heat and the window open all day, but worse. You have the windows all closed right, how hot does it get inside the truck?

I'd be a girly man, and have the AC running until I had the truck staged! o_O
Do you think they'd mind the dripping water under the engine? What's the rpm limit for an AC compressor, I could bypass the WOT relay, maybe?:confused:

AC is not allowed at the track, they don't like water dripping on it.
But the ride there and back home it's ok.

Explorer vs Honda Civic
From 05-31-2019


Love it!
Are you short shifting from 2nd to 3rd? It just kinda sounded like it in the vid.
Although, I do have to be careful how loud I make the audio since I'm at work. lol

I honestly don't have any idea what rpm the 1-2 shift was occurring, the race was so long ago I don't remember.

The 5r55 will skip second gear while under the correct conditions

08-24-2010 12;03;22AM.jpg

That gives me an idea for an experiment at a later date,
I could tune the transmission to skip second gear altogether and see if it runs quicker or slower 1/4 mile times.

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I think part of how the 5R survives what it does, is the close gearing. The difference between the gears is much less than some of the ratios of the four speed automatics. Bands are weaker holding components than the clutches in drums. That's why the later 6-speed has no forward bands, and is stronger than earlier units.

I look at the ratios of the 6R80, and 6R60, and those are even nicer than the 5R. The 1st gear of the 6R's is 4.17:1, which is more than any 5-speed(5R55W etc). If those had comparable transfer cases, I'd think hard on making one of those work.

Gear ratios:

AOD - the first four forward speed, 2.40, 1.47, 1.00, and .67:1 (same as AODE)
4R70W - has four forward speeds, 2.84, 1.55, 1.00, and .70:1
5R55E -- with five forward speeds, 2.47, 1.86, 1.47, 1.00, and .75:1
5R55W - with five forward speeds, 3.22, 2.32, 1.55, 1.00; and .71:1 (5R55S is very similar)
6R80 ---- with six forward speeds, 4.17, 2.34, 1.52, 1.14, 0.87, and .69:1 (same as 6R60)