M20 throttle body differences

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Lurch320i
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Post Sat Mar 28, 2015 9:58 am

I got another throttle body for my 89 325i sport and its a bit different to the original

The vacuum take off for the brake servo isn't there and also it has two holes after the butterfly where my original has just the one where the brake servo pipe attaches

Is there a way to block/adapt these to make it work
Thanks
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Brianmoooore
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Post Sat Mar 28, 2015 10:20 am

Lurch320i wrote: The vacuum take off for the brake servo isn't there
it has two holes after the butterfly where my original has just the one where the brake servo pipe attaches
Yes, it can be used, but these appear to be contradictory statements. is your new TB the one pipe later type or the earlier two pipe type, with the weird servo plumbing that also connects to the big air hose.
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Lurch320i
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Post Sat Mar 28, 2015 11:06 am

Sorry if I was a bit vague Brian

Mine has two holes after the butterfly but no pipes sticking out, that's what I meant by the take off pipe isn't there
I tried to take a pipe out of a spare tb I had but couldn't get it to budge

How will I get this to work with the servo and block the other hole up?
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Brianmoooore
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Post Sat Mar 28, 2015 2:15 pm

Any chance of pics?
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Lurch320i
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Post Sat Mar 28, 2015 4:37 pm

Yeah I'll get some pics for you and update it
Cheers Brian
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Lurch320i
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Post Sat Apr 11, 2015 1:22 pm

Right sorry it's taken a while to get pics
I've been busy and keep forgetting

My stock TB
Image
Only has one hole in it and that's for the brake servo vacuum

My btbb
Image
It has two holes

What can I use to block one off completely and then put the vacuum fitting in it?
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Brianmoooore
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Post Sat Apr 11, 2015 1:27 pm

Top one is late type, bottom is earlier type, and has the two elbows missing.
These are pressed in, often work loose, and epoxy adhesive is the usual cure. In your case, you only need one, so block off the other hole completely. Tap a thread into it and screw in a plug would be my choice for doing this.
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Post Sat Apr 11, 2015 1:30 pm

Being lazy, I used quiksteel to block the extra hole and it does the job fine.
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Lurch320i
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Post Sat Apr 11, 2015 1:52 pm

And then a 90 degree angle and barb fitting to get the servo vacuum pipe on?

I tried to get the elbow out the throttle body to put into my bbtb but couldn't get it to budge
any reccomendations about what to get to block off and what pipe to get to thread into it?
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Brianmoooore
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Post Sat Apr 11, 2015 2:28 pm

You should be able to get the one out of your old TB easily enough. They usually come loose on their own.
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Lurch320i
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Post Sat Apr 11, 2015 2:54 pm

I'll have another go but it was Jammed in good and proper

And didn't want to snap 25 year old metal