TBI throttle plate modification

[howieschoon]

Well, here's anonther question for every one. What do you think about this. It is a modified throttle plate from a throttle body injection system (it is really from an MPI system but is almost identical to the one on my TBI). I made some grooves in it that I hoped would help collect some of the liquid fuel on the plate and funnel it into the small hole. The pictures are not the best (neither is the grinding) but hopefully you can get an idea of what I did. I made this several years ago and have never used it. I know that if the hole was too large the idle would be much too high (if it was big enough that it couldn't be adjusted any lower).

Does any one have any suggestions, good or bad?

My thought was that the fuel would be more in the middle of the throttle bore and would therefore be less likely to stay a liquid on the walls. It would only be helpful (possibly) at idle and very small throttle openings. Much of the air even at idle passes along the edge of the plate, so I don't know for sure how useful it would be.

Has anyone done any modifications to a TBI seup to help with part throttle atomizaion? Is it as bad as it seems it would be?

Thanks,
Howard

[Devious]

I like the radius to the leading edge of the throttle plate. I do this regularly in ITB systems. But the trailing edge should be sharp to improve the shear of liquids that may collect on it - if the plates are wet.

Where are the injectors located - in the throttle body, or above it?
Can you post pictures of the specific throttle body?

[howieschoon]

Hello Devious,
The injector is above the throttle body. I attached the only picture that I currently have, unfortunately it is probably not all that helpful. I didn't take a picture of the sides but I made both edges fairly sharp. Having the leading edge rounded is probably a better idea. What do you think of the hole/trough? I drive this car around town most of the time so MPG at little to no throttle opening is what I am after. I know that I can close the throttle plate atleast a little more to, hopefully, compensate for the hole in the plate. I have had it closed off far enough that it wouldn't run.
Thanks,
Howard