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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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I started with a wire brush, but the file did the job better to knock any corrosion off. The hub is good now I think, the pulley is just nearly a perfect fit. My PS pump has 205k miles on it, and it's interesting to see how much play is in the pump shaft. My SOHC has one that I bought new from Ford, and it had the same play in it when I got it. I hope those are supposed to be like that. I think they are reliable, but the high price makes you wonder if it's worth it versus the old style of PS pump.

For the TB, the air inlet pipe I was hoping to use a big stainless "L" shaped pipe like the MAC kits came with. The upper radiator hose might make that tough for a 4" pipe though, we'll see.

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Belt Stretch

Just an update on the 8 Rib belt.
Pictures comparing new belt vs belt with 6 WOT runs (and driven to track).
I love the belt wear indicator on this tensioner.
1 New Belt.jpg
2 After 6 runs.jpg

Here is my current Throttle Body.
It is a single blade LFP (Lightning Force Performance).
I made the throttle cable bracket when I had the Lightning Supercharger on it. The bracket used to be on the bottom.
Here is my current intake tube as well, Home Depot 4 inch sewer pipe. Love this stuff.
1 lightning TB.jpg
2 lightning TB.jpg
3 TPS.jpg
4 Air Tube.jpg

Ford Racing Throttle Body

Here is the throttle body I plan to use after I finish messing with my new injectors.
I had to make this bracket for the cable. I just started bending some scrap aluminum I had in the garage. I messed up several times but was able to over come it by adding a few pieces. It looks over engineered and king of crappy but maybe it will look better with some black spray paint on it.
The last two pictures show what my Lightning Throttle body looks like installed, vs how the Ford racing one will look.
I took it back off because I changed Injectors and don't want any other changes at the moment, until I finish tuning it again.

Fourth picture down shows the screws that hold the cable guide on, I flipped the guide 180 to make it work on my Explorer.
Note the TB is upside down when installed on my truck due to clearance problems with the Windshield wiper motor.

I should also note that I think the Ford racing is rated at 1400 cfm and the Lightning is rated at 1800 cfm. If my truck loses power I will go with a Ford Racing Single blade(they are about 600.00 though). (don't quote me on the CFM's.)
1 Cable Bracket.jpg
1 Ford Racing TB.jpg
2 Ford Racing TB.jpg
3 TB Cable guide.jpg
5 Old Lightning TB.jpg
6 New TB Installed.jpg

Thanks for those detailed pictures and the descriptions. That has a lot of potential for anyone to do something similar to that.:thumbsup:

Marking that tensioner is a good idea,i think ill do the same.

Tensioner Spacer

So the other day I found that the belt had jumped one rib forward on the tensioner. I had been keeping an eye on it since I started the 8 rib belt project.
Switching to the newer style alternator bracket would make putting a spacer behind it easier. I originally had a Mustang 4.0L bracket but one of the alternator bolt holes was further back than the Explorer. I had drilled it and made it work but was not completely happy with it. I got a bracket off a 2004 Explorer 4.0L and today made a spacer. This should keep my belt in the right place, even at high rpm's.

Nicely done. You shouldn't have any issues with that


Thanks Ahodges!
My biggest fear was having the tensioner turn and spin the spacer, with the screw and nut behind it I am somewhat confident that it won't.

4 Wire TPS

The Ford Racing Mechanical Throttlebody has a 4 wire TPS on it just like the newer drive by wire(Electric Throttle Control) TPS's.
I have not run the truck with this throttlebody yet and I have had it for a year.
Time to get busy I guess.
I cut the old TPS pigtail off and added a couple Deutsch connectors so I could easily reconnect it. Then using the same Deutsch connectors I made a new pigtail for the 4 wire TPS. I am only using 3 of the wires going to it.
Now I can change back and forth for testing purposes.

Note: I am using a different camera, kind of cheap and I don't know how to use it fully.
1 New TPS.jpg
2 Connectors.jpg
3 connectors.jpg
4 terminals.jpg
5 crimper tool.jpg
TPS adaptors.jpg


So I still didn't try out the Ford racing throttlebody yet.
I did get through inspection and now have two more years before I have to do it again.
I reinstalled my 60 lb injectors and was finally able to get the HEGO test to run/pass with them in. So no more swapping injectors every two years.
Saturday I spent 6 hours tuning the truck. The A/F is pretty close, should be good enough for racing. Just in time, April 24th is my first race of the year.

With that injector monkey off your back you just free'd up some time. Now you can focus on that maf. Harnesses look perfect. No worries of those giving you issues. Great idea, and very professional (Wait a minute, you are one). We have all seen a lot of professionals do some not professional work, but not yours. Top notch, and what your 1/4 mile times definitely prove it.
You are 2 weekends ahead of schedule.

Were all looking forward to seeing you crush 12.83, a 10th at a time.

Time slips

Thanks Dono!
I don't think I will be beating the 12.83 times at the beginning of the year, but maybe at the end of the year.

Fuel Block

I got a new RPCaster fuel block.
The only difference from the old one was that there is a fuel test port on it now.
This should make things easier to test in the future.
I did change the fitting on one end since my configuration is slightly different.
Also I came across a gauge a while back and had it sitting around waiting on the right moment to install. This weekend was the right moment.
This gauge has yellow numbers and only goes up to 100 psi. More than enough for me.

Spark Plugs

Put some new spark plugs in, getting ready for tomorrows race at Maple Grove.
NGK TR6 / 4177
Gapped at .030

Even washed the truck, hope the bugs stay off the windshield. lol.

I can hardly wait to hear the results!!

Yes that extra 1000lbs of body weight is a bigass handicap. It's still very fast, stock being nearly five seconds slower. I think a Mustang with that power would be deep in the 10's.

BTW, put some RainEx on it, by hand. It makes everything let go better, bugs too. Wipers clean off bugs easier with it. Don't use a rag to apply, use a hand. Squirt some on and spread it with your hand. That uses less RainEx and leaves more on the glass, less in a rag.

BTW, put some RainEx on it, by hand. It makes everything let go better, bugs too.

Just so happens that I have two really big dead bugs under my wiper blades, one on each side. LOL. Picked them up on the way home.

What a coincidence. lol.

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he'll probably say something like "it only ran a 12.9".....yea, like its a problem

My best run was a 13.34
my worst was 13.61

I never hit second gear today, PCM commanded a first to third shift each time.
It was my fault.
I was too lazy to fix it at the track. 1-2 was only 2 mph lower than 3-4 in the shift schedule, now it is 4 mph apart. I changed it after I got home, lol. Had some Idle problems too, had to add 20% to my Idle air adder for drive and neutral.

I got three time trials in and lost my first elimination race, so I was eliminated.
Was a great time though, I needed the sunlight and fresh air.