Topic: $35 EBay Throttle Body Spacers?!

[Jeffy]

Well, whatever, it still has more to do with the pulse wave.  

[wrangler387]

hehe, i wonder what harmonic and at what rpm range the jeep engineers made the stock manifold perform at. :?:

[midnightcwby]

Ok, I just bought one of these on EBAY like 3 days ago.  I actually got it for $24.00, not $35.00 like I originally saw them on there for.  I'll be sure to take close up, detailed pictures of this thing so everybody can see the quality and I'll include measurements made with recently calibrated/certified machinists measuring equipment (thanks to my uncle).  This will verify bore diameter, ect.  That way everyone else can be totally sure of what they're getting before THEY order it.

I read the sellers reviews, and everyone seemed to be happy with the products they received from this guy, so we'll see.

[Jeffy]

I believe the height of that is the same as the Poweraid/Airaid spacer.  They started making them right after they came out.  I think Hesco is the only one who's thicker.

[midnightcwby]

I'll be sure to measure it and post.  It's advertised as 1". We'll see :D

[midnightcwby]

Oh, and HESCO is awesome!  I love them...

*EDIT*
They arn't the cheapest though...

[midnightcwby]

Ok, I finally got the spacer in.  I don't have pics just yet, but I will tonight.  It looks EXACTLY how I hoped it would!  Very nice, quality work.  All the stuff is included. The instructions are there, but not necessary (who can't figure out how to put this on?!)  I just wanted to let every one know who was looking into buying one of these cheap E-BAY spacers know that this seller is TOP NOTCH.  I am totally satisfied with my purchase and I can't believe how much cheaper these baby's are than the other ones with all the gimmicks and fins and stuff.   Good buy!
The sellers ID is: res069tu

Look him up!  He's had plenty of these things when I won my "buy it now" bid. I got mine for $29.85, sweet deal.

Thanks for listening to me ramble, hope this helps ease someone’s mind.

[midnightcwby]

The spacer is installed and all went as expected.  I took pics during the tear down and assembly.  I took measurements with my micrometers and my inside telescoping bore gauge.  I came up with an over all height of .9825” and I took 2 bore measurements at 90* angles of each other, parallel to the bolt holes.  These were 2.439" and 2.441". The average bore diameter would be 2.44" then, just a touch less than 2.5".  I found the intake manifold and the stock throttle to be SIGNIFICANTLY smaller in diameter; so much so, in fact, that I didn't have NEARELY enough time allotted to the removal of all of the excess metal that needed to be removed in order to match the intake to the spacer.  The pics show just how much metal needs to be removed; I'll post them tomorrow after work,  There is a lot more than I'd throw my poor little dermal at!  I'll have to get some stones for my die grinder and fire up the compressor.  

After a short test drive I have a little feed back to offer.  I did indeed notice a difference in throttle response and crispness.  In fact, most of the difference I personally felt was at part throttle.  I seem to have power sooner in all the gears. By sooner I mean a little bit of a noticeable difference in RPM and a larger difference in throttle angle.  It doesn't seem like I have to press the gas as much to maintain speed or accelerate.  In fact, I noticed that I don't have to feather the clutch quite as much from a dead stop as well.  5th gear is now useful for me at 35ish.  I can accelerate from 35 with out being required to drop to 4th like I was just a little while ago.  Full throttle feels a bit more powerful as well.  I let her wind out to 5500 through 3ed and it seemed to be pulling faster and stronger (not to mention a little louder!) than before.  

As to whether the MPG has increased a point or two, I won't know for a tank to two.  I drive 50 miles round trip to work, so a tank doesn't take long to use.  I hope I might squeeze an extra few miles out of each tank!

[Jeffy]

When you match the port you should try and match each to the gasket.

[midnightcwby]

That's what I'll use for the template.  The pics I took show that the gasket is exactly the same size as the new throttle body spacer.  It looks like they used a gasket as the basis for their measurements when they CNC'd these things. Interestingly, the stock gasket that was on the old throttle body is also the same size as the new gaskets; roughly 2.5".  

I'll be taking the throttle body off and replacing it with my 4.0L TB soon, so when I have it off, I'll take the time to remove all the material on the intake that needs to be taken off to match.

The intake manifold is interesting.  The runners are separated by an aluminum wall all the way up to the plenum. This does present a problem while taking material out of the mating surface, though.  The walls are blended into the TB mating surface, so in order to open the hole, you need to be careful while working around these features.  I'm wondering what would be to gain by sharpening the edge of these walls so they slice and split the air more efficiently as the air is divided into the runners. Probably won't make a noticeable difference in any power, but extra efficiency helps fuel burn cleaner and more completely usually, so it shouldn't hurt if it's done with care.
 

This one is of the new spacer


This one shows the difference in size of the stock TB and the new spacer


This one shows the difference in size of the intake and the spacer, alot more of a difference than I was expecting!


Here's another angle


This shows a black painted ring on the intake/TB mating surface. This ring is the overlap of the intake manifold that needs to be removed to match the new spacer (the ring was made using the gasket as a template).


This one shows that the gaskets are the same size as the TB spacer, so the gaskets should be used as a template to make the intake match as well.


another angle of the gasket on the TB spacer...


Here's a pic of the 'adjustment' that had to be made to the stock throttle bracket to make it work with the spacers given... (you'll see a part of the bracket that had to be bent to clear the fuel rail)


Here are some finished shots

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[Jeffy]

No after pictures of the grinding?  And why didn't you clean off the TB a little. LOL!    :wink:

[midnightcwby]

I haven't yet begun to grind!  I didn't clean the outside of the TB because I have my 4.0l TB sitting in my room ready to be cleaned and installed  I picked up some carbide grinding bits and some shaped stones from Tractor Supply Co. last night.  I have tomorrow off of work, so the grinding will begin first thing in the morning.  I'll have to take my time to get the intake right, you can always make a small hole bigger, but you can't make a big hole smaller! Not easily anyway.  

On another note... I noticed my 4.0l TB has a venturi formed in the lower portion (intake side).  The air tube side is much larger, as is the butterfly valve; Should I have this venture machined out to match the size of my TB spacer or at least chamfered a bit to smooth out the transition?

[midnightcwby]

I've been thinking about the venturi that is designed  into the base of the TB a little more.  This venturi seems  to match the stock diameter of the intake, or at least I believe it does.  I'll be checking that tonight when I get out of class.  The only thing this venturi could POSSIBLY be for is the idle bypass outlet port, and if so,  why the hell does IT need a venturi?!  It just offers a passage way to bypass the throttle valve. There is a portion of the venturi that's missing too.  This is where the idle bypass port is.  What is the need for a vaccume to be applied to the idle bypass port? it seems there would be more to gain than to loose by removing this bottle neck and then, of course, opening the intake manifold to match the new bore.  While I'm in the intake taking out metal, I'm going to shape the "air splitter veins" too. They look like they're there to help direct the incoming air down each runner.  I'll take better photos of these and the work I do to them (if I determine I can do anything to them at all!).

Anyway,  like I said, what is this venturi for, and can I remove it?!

[MA2LA]

you can remove it. its a commen mod for 4.0 crowd and works well. the spacer you have is the same one i have. the stock 4.0 tb is about 1mm bigger than the stock 2.5 intake opening.

[wrangler387]

I dont know if it has any other reason, but almost all throttle bodies taper. Increasing velocity into the plenum. If you are going to try and shape it, do not make it have any sharpe edges (knife edging some people call it), Keep them round.