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Discussion Starter #1
I had done the Ported TB thing a while back an really noticed a big difference in the throttle response.

After reading the recent posts about the ported TBs I decided to go one step further. I used a 2.25" hole saw in a drill press to bore the TB.

This took about .25" of additional material from the bore. I then used some wet or dry sandpaper on a 2" tube to do the finish work. Then I made a new flat throttle plate from aluminium. I ended up with about a 60mm TB from the stock core. So far, so good. Idle seems to be OK and I can feel a little more pull.

Oh yea, I did have another stock TB just in case.

Thursday I'm going to change to a 2k manifold and will post some pics for those interested.

[ 12-10-2002, 09:04 PM: Message edited by: Blue01Street ]
 

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I bet we could field a good team for "Junk Yard
Wars" from this website. How did you cut the plate? It's a bit oval shaped, isn't it? What did you do to smooth the edges? I'm sure alot of
jetters would like to know. I would like to try this to see how it performs against my 65mm TB
for s**ts & giggles.
 

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Discussion Starter #4
I cut the plate from a junk piece of aluminium I had laying around. Took a good bit of work with a file and sandpaper to get it just right. Yes it has a very slight oval shape. Not much though. And the edges are beveled to match up with the sides of the TB because fully closed is still a slight angle.
 

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you have a PM blue!
 

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this was exactly what i wanted to know. accept i have a mill to cut the alluminim. i want to make a new intake manifold. Oregon is great country.
 

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wait a minute. mind u folks that takin a hole saw down thru ur tb is cause 4 killin it if now precise. but my question is, u cant take another .25in out of the bore w/o goin into the idle air inlet. details and pix plz. b/c if u did what u did. it makes a great experiment. but i dont c it as feasible or worth the time 4 most 2 go that far.

hit me up,

-Ult
 

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Discussion Starter #8
You're right about almost killin it. The .25" is just an estimate. I ended up with about a 2.3" hole through the TB and the side by the idle air is VERY thin. I will post some pics tomorrow when I take it off again to change my manifold.
 

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Discussion Starter #9


Not the best pictures, but you can get an idea how much is taken away. If you've done the Focus Hacks TB porting you can compare how much epoxy (white) is showing where the overhang was. I think that the flat throttle plate helps also.

The most important part is the fit of the throttle plate. ANY slight gap will bring your idle up quite a bit. What looks like a gap in mine is where I beveled the top and bottom edges for the best fit at the slight angle of the closed position.
 

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well, whether is helps or not, i'm impressed. gj. wonder if u could lob a lil bit of epoxy on the backside of that thin idle air hole (technically the inside wall) 2 firm it a lil w/o restricting the idle air flow. again i'm impressed, has me thinkin bout hittin the salvage yard and scorin 1 more TB 2 play with.

-Ult
 

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Discussion Starter #12
You could add epoxy to the idle air passage because the hole in the intake manifold is quite a bit smaller than the passage in the TB. I don't know if it is worth gouging it out any more or just getting a 65mm TB.

It's a lot of work, but it doesn't cost anything.
 

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This was my attempt to get rid of that high RPM hang and add engine braking by decreasing the Idle Control Valve Port, and it worked. The RPMs dropped much quicker and down shifting slowed the car down considerably better than stock, but this set-up also killed power. Why? I didn’t take into account that the ICVP allowed a steady flow of air into the engine no matter what the throttle plate was doing. This flow of air contributed to the total volume that was going into the TB. The only way to compensate for this loss would be to increase the size of the throttle plate hole at least the amount you decreased the ICVP size. I could not figure a way to do that without buying a bigger throttle body,until now.This might make-up the difference.

Opinions?
 
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