How To: Modify a 4.0L OHV Throttle Body..

[jd4242]

your cutting the shaft in half.look at the pic close in the first post and you can see what is removed.

 

[Spdrcer34]

milling....that's the wrong word...but the end result is the same.

The throttle shaft has a slot cut in it, so the throttle blade can slip inside, and get screwed in to place.

You are removing the front/top section of the shaft at the slotted opening.

You need to keep the back/bottom section in tact, as that is where the threads are, that hold the screws in place.

Ryan

 

[archlab]

More Good Info! Thanks.

I needed some money, so I sold the BBK Throttle Body off of my Daily Driver...not REALLY wanting to go back to a stock TB...I was reminded of the ThrottleBody mod that 'aldive' had done to the Ford Motorsports TB on his SOHC ( http://www.explorerforum.com/forums/showthread.php?t=172480&highlight=throttle+body+mod )...I wanted to do the same thing...well 1/2 of what he had done at the least...

So this is how I did it:

...

And that's it...You're DONE!

Ryan

I like it! Thank You.

 

[jd4242]

It may be my phone but think some of the pics have disappeared

 

[Explorin'VA]

Yeah, some of the pics are missing. Any way you can post them again? I want to do this mod but would like to see all the pics.

 

[natenkiki2004]

I think I'll be performing this mod in the near future. I understand what needs to be done despite the missing pictures. Along the way, I'll try to take some but unfortunately, I don't have a "real" camera, just a tablet but they should be good enough for reference.

 

[xplorernewb]

none of the pics are working for me..... anyone else know where to locate another tutorial like this with pics?

 

[dcrank44]

New to this forum.
Can't view pics? Please help

 

[natenkiki2004]

The pics are long broken. Basically, inside the throttle body is the throttle plate, it is rotated by the throttle to allow more/less air in. The shaft that holds the throttle plate is slotted, the plate sits in the middle of the shaft. The rear half of the shaft is threaded, for the screws holding the throttle plate in but the front half of the shaft just has holes.

This modification cuts the front half of the shaft off. This, in theory, makes for smoother airflow over the throttle plate, without the hump of the shaft in the way.

There's very intricate grinding involved to do this cleanly and you better use some loctite on the screws that hold the throttle plate in place.

 

[dcrank44]

Thanks for the reply, is this mod even worth the time of doing?

 

[jd4242]

Thanks for the reply, is this mod even worth the time of doing?

Depends on what you value your time..free mods always are wroth my time,but i enjoy being in the shop working on the trucks..

First mod id look at is the cable mod..look under your dash at the gas pedal and lift it up to see if there is alot of slack in the cable and end of pedal..if so your butterfly is probably not even opening all the way..thise cables are known for stretching. .you place a zip tie around the cable end and pedal cable hole..essentially making the cable shorter opening the butterfly farther

 

[vq5speed]

So after reading this thread it got me wanting to mess around with the extra TB I have. Its off a 95 the only difference I can see is the 91 has 1 single hole in the throttle plate. The 95 has 2 but there smaller holes. The throttle linkage looks almost the same slightly different but I think it will still work. So anyways not going to show all my steps but just show you my finished modification. I think most of the gain could be had in narrowing the plate cross bar. Widening the bore bigger really doesn't help much unless you can make the throttle plate bigger. Cause air still has to pass through what ever the size of the throttle plate is which I measure to be about 60mm. So opening up the body to 65-66 does nothing if the air still has to pass through 60mm opening. I went and googled Modify throttle body to see what people have done to them. I saw where some just thinned down that cross bar. Saw one where they took a section out between the two screws. Then I saw where they completely eliminated one side of the bar and thinned down the other side. I liked this idea.I didn't touch the bore at all I might smooth out the small ledge you see. If I do try to widen the bore I'd look for a bigger throttle plate off some other TB to fit into mine.