To answer your original question...the pits are not a problem. Those are the results of air bubbles in the molten metal when the TB casing was cast at the factory. Nothing to worry about.

 

I have my stock TB sitting on my lap from my 2001 5.9 (the 50mm I have was a survivor from my 1996 ram).

TOP:
The air horn is wide, then it tapers in (gets smaller diameter) until just before the butterfly. So the top has a smaller passage than below.

Bottom:
There is a lip on the bottom that makes a little STEP where the bottom of the throttle body is actually larger than the part where the butterfly sits.

Also, if you really hone out the passage to 50mm, your butterflies will be too small. I believe our butterflies are 50.19mm in diameter. They do not sit FLUSH when the butterflies are fully closed, they actually sit at an angle in the "cylinder" of the throttle body. SO, the butterflies need to be slightly larger in diameter to actually fit.

SO, Drew and Augie are both right. I don't think that they realize that they are arguing about apples and oranges.

In the throttle body, there are FOUR places where the diameter is different:
1. Top of air horn
2. a few CM (3-5 depending on what half of the butterfly you are looking at) Above the butterflies where there is a taper that moves INSIDE.
3. The taper right below the above starting from above the butterfly to the "step" or "lip" that is 5cm from the bottom of the TB.
4. The 5cm of the bottom of the TB that is past the step/lip

So, there are 4 different places to measure and the top and bottom of the TB have places that are BOTH larger and smaller. 2 measurements above butterflies will be bigger and smaller...technically three because you have the top of the air horn, the taper INWARD and the taper OUTWARD.

 

Cpta the peace maker finally steps i. It's unfortunate this got so of topic . But here's another update if you can build save the money if you can't build it buy it's definitely worth the money for the throttle response but I can't seem to keep my foot out of it sO my mpg is worse .

 

the restriction down to 47mm is above the butterflies not below from the butterflies down its 50 mm or larger...thats the only thing that matters for making a stock 47mm TB a 50 mm one....This is what the disagreement was about..

To keep facts straight, It got ugly when Drew suggested I was lying and fabricated the whole thread I made and pics I posted when I modified mine because He was so certain of the opposite.... And then when proven wrong instead of apologizing and owning up to his mistake he just made an excuse and disappeared from this thread...And thats all in writing, Its not my opinion of what took place...We all make mistakes it how we deal with them thats important... I stick my foot in my mouth here all the time and have apologized for it..


The little tapered section at the bottom is irreverent unless one wanted to go larger to the 51.16mm opening of the little cut out taper at the very bottom.

Lemunman your right its unfortunate things got off topic and went this way... I was just trying to provide a low cost alternative to the fastman when it comes to 50mm sized TB's.. and was trying to relay how easy they really are to mod without fear of screwing up how the plates seal in the openings...

 

^^^Agreed.

 

It is pretty easy to get confused when you look at a stock throttlebody because the step on the bottom gives an illusion that there is a taper INWARD at the bottom. Also, you can get confused if you measure the diameter of the air horn o the top, because it is larger than where the actual INWARD taper is at the top.

With all those tapers and steps, it makes it seem like Dodge wanted a more turbulent flow with the air. That makes sense because of the pencil injectors that came stock with our trucks. It would help atomize the air/fuel mixture.

Augie, one question. Do you have problems keeping the air hat gasket centered after grinding down ALL the tabs that would keep it from shifting? The fastman and most other professionally milled TBs still keep remnants of them.

Like Rich's from hi-potek: here is a pic

http://stores.hi-potek.com/-strse-11...For/Detail.bok

 

to make things crystal clear: I was wrong. There is a slight inward vortex on the OE TB UNDER the blades, but it is insignificant to what happens above the blades..

I've assisted in the mod on a TB, insofar as I sat there and drank beer whilst the other fella dremmeled away.. And, I ordered a fastman 52mm.. I inspected both TB's sitting side by side, and determined that I flat out wasted my money buying one- though there is now way I could make it as purty as Dan does..

I was absolutely certain, in my mind, that the taper happened below the blades- in my minds eye, that's what I saw- my memory is faulty and flat out wrong.. I cry your pardon as for accusing you to be wrong, when it was me that was wrong..

I haven't been avoiding this thread, though- I've just had other things going on this past week.. I'm pretty arrogant, but notsomuch as to not accept responsibility for my folly..

 

So when are you two homos gonna kiss and make up?


Jk...


About the kissing part.

 

Lmao...

 

LOL, too funny.