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> Choke mods, Throttle spindle machining
post 6th February 2018 21:38
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1.4 16v

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Local Time: 11th August 2020 20:36
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Hi all.

I've started some work on the throttle body. Reducing the diameter of the spindle between the screws. Object to reduce the area in the airflow. The two pictures show where i've removed material, theres more to go without weakening it too much.

Attached Image
Attached Image

The next step is to knife edge the throttle plate on one side, the side thats presented to the airflow. I'll chamfer it at about 30 leaving a small amount of the original diameter there to seal in the choke. I'd like to machine it but Ill have to make an elaborate fixture to hold it, Filing it may be the answer but I avoid hand tools if I can!

The area that the plate rotates in is at a bit of an angle to the inlet and outlet side, There is an obstruction on the lead in which I'd like to machine out but I havent quite got my head round the angle issue yet.

Will keep you posted..

Can I start again?
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dante giacosa
post 7th February 2018 10:20
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1.6 16v

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Hey Desperado-

that's quite a mod!

Have you got an anemometer? I think it would be worth getting cheap one so that you can actually measure the benefit (although admittedly you are halfway through already)

I did something 'like' this at work, where we had the bright idea of sending the airflow from a fan through alternative ducting- using the anemometer we were able to show a nominal flow-rate before, and after the modification.
As it happens; the tighter radius on the bend of the new part inhibited a better flow rate, and so the original ducting was provably better...
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