Greg_E

iTrader: (4)

This is my first attempt at porting a throttle body, and I don't want to mess up.
There's a ridge on the top half of the TB. Should that be removed? In the picture below the solid green is one side of the ridge, and the green hatch marks are the other side of the ridge. The black line is where the blade is, when I push it all the way closed.
The bottom half has a smaller ridge, but it looks like if you mess with that it will change how much air gets past the blade. I should not remove material from there. Correct?

I've read the "How To" threads, but it's tough to see from the pictures, what's been done, especially after they're polished up.


Thanks for any help.

0235SS93

iTrader: (1)

yes, that's what you want to remove

markzeronine

does this really help?

Greg_E

iTrader: (4)

Thanks for the reply.

Bad Blue WS6

iTrader: (41)

other than the typical fancy stuff, you should also feather out the front ridge to...like this

teke184

iTrader: (5)

you DON'T want to touch ANY of the material that is around the edge of the blade. that will allow air to bypass the blade and throw off the idle and who knows what else.

everything you remove comes from IN FRONT of the blade.

that ridge should be removed from the entire TB. not just the top.

socmguy

iTrader: (18)

Be very careful not to go past the blade. If you do, the TB is now trash.

teke184

iTrader: (5)

here's a drawing of what i removed when i ported mine. all i did was throw it on a metal lathe and machine off the "lip"...took all of 20mins.

granted the approach angle could have been massaged a bit more...but i don't feel it was worth it.

socmguy

iTrader: (18)

very nice diagram

Greg_E

iTrader: (4)

Thanks for the pictures and diagram guys.
Looking at the diagram it would appear that if the lip at the bottom of the throttle body is removed, it will allow more air past the blade at idle. Does this affect the idle, or is the PCM able to adjust for the change? The blade on my TB is in the position shown with the red line in the diagram and noted as "TB blade at part throttle position". That is the normal position of the blade at rest. I have to press on the blade to move it to the fully closed position. The pictues of the cable version TB looks like it's fully closed, at rest.
Also it would appear that removal of the bottom lip is what is responsible for most of the improved part throttle response.

ApexVIII

iTrader: (17)

yea thats pretty much where you want to remove, post up som pictures when you get it all done!