I just bought a ported tb and my car now idles between 1500 and 2000 rpms till i come to a stop. When i get to a stop it is still about 100 - 200 rpms to high. So i put my stock tb in and all is well again. Problem is my car was tuned with the ported one on it and I would like to make that tb work. How do i get the ported tb to work?

 

It sounds like the TB is ported a little too much around the TB blade.

Here's a simple check for you:

- Take new ported TB and hold it up to a light
- If you see some or alot of light around the TB blade and TB housing, the TB was ported to much

If it's ported too much you can either take a chance and fill in the low spots with JB Weld and sand down till it's stock like or start over with a new TB.

I'd vote for starting over with a new TB since I wouldn't trust the JB Weld, you never know if it would ever come off and go into the engine.

Bill

 

I noticed the ported tb has a second hole drilled in the top side of the blade is that probably the problem? i held it up to sunlight it seems to be flush the whole way around the blade. I wonder if just taking the blade off of my stock tb and swapping it over to my ported one if that will fix the problem.

 

Thats what I did and it took care of my idle problem.

 

A lot of guys that port throttle bodies will knife edge the trottle plate. It is very easy to mess that up. Changing the plate would surely help there. Also, you don't need any extra holes in the plate. That is an easy way out if you have a cam, to help get it to idle.

 

yup. swap blades. for a test let it idle with the ported tb and put your fingr over the second hole if it fixes your idle you found the problem.

 

did swapping the blades fix it?

 

yes it did