Author Topic: talk to me about widening the inlet?  (Read 2566 times)

Offline blueandy

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talk to me about widening the inlet?
« on: 17 March 2013, 10:13 »
A wise old sage once told me that there is a nasty lip on the inlet, and that it needs porting out.

Anyone got anything more to add please?
is it as simple as getting a die-grinder on it and smoothing it out?

Offline whileoceanasleeps

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Re: talk to me about widening the inlet?
« Reply #1 on: 17 March 2013, 10:16 »
A wise old sage once told me that there is a nasty lip on the inlet, and that it needs porting out.

Anyone got anything more to add please?
is it as simple as getting a die-grinder on it and smoothing it out?

i don't know about a lip on the inlet but there's a lip on the throttle body edge against the inlet that you can port out. as standard the opening on the throttle body is a smaller hole than the inlet due to this (i'm assuming you mean for a 16v bud?)

Offline blueandy

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Re: talk to me about widening the inlet?
« Reply #2 on: 17 March 2013, 10:25 »
yes mate, my abf.
It must be the TB as you state.

On my old scoob it was easy as you simply ground out the sooty marking, smoothed the finish and then thoroughly washed it, is it the same process?

Offline whileoceanasleeps

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Re: talk to me about widening the inlet?
« Reply #3 on: 17 March 2013, 12:28 »
yes mate, my abf.
It must be the TB as you state.

On my old scoob it was easy as you simply ground out the sooty marking, smoothed the finish and then thoroughly washed it, is it the same process?

grinding with a dremel is ok but I found a better finish using a file, then coarse to fine sandpaper, wet on the fine grits. bit more time consuming tho! if you look at your TB you can take out the ramps either side of the butterfly to make the inside perfectly circular

Offline blueandy

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Re: talk to me about widening the inlet?
« Reply #4 on: 17 March 2013, 15:31 »
many thanks for the guide, I'll be doing this one.

VW BUSH

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Re: talk to me about widening the inlet?
« Reply #5 on: 17 March 2013, 15:48 »
I you damage the area where the butterfly's shut off or the flaps themselves you will have all sorts of running issues, don't just attack it with out masking it off and marking it up.
Buy a throttle body and play with that one rather than fck the one on your car
I suggest using a high speed dremmel type tool with carbide burrs to shift the main stock and then polish up with a bobbin cap.

You cant really do a proper job without a lathe.

Offline whileoceanasleeps

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Re: talk to me about widening the inlet?
« Reply #6 on: 17 March 2013, 18:46 »
lathe is probably better but I think you can do a good enough DIY job if you don't have access to one. as bush says all you just have to be careful not to take any from the butterfly area. go for it bud

Offline Khare

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Re: talk to me about widening the inlet?
« Reply #7 on: 17 March 2013, 21:01 »
I suggest using a dremmel too. With a file you're going to be going across the butterfly seat and if you catch it you're going to ruin your throttle body.

Get a dremmel and get some cutters like these

http://www.ebay.co.uk/itm/Dremel-115-High-Speed-Cutter-7-8mm-x-1-FREE-POST-/180705824191?pt=UK_Home_Garden_PowerTools_SM&hash=item2a12e80dbf

http://www.ebay.co.uk/itm/Dremel-117-High-Speed-Cutter-6-4mm-Multipack-/190562510738?pt=UK_Home_Garden_PowerTools_SM&hash=item2c5e692792

As well as a lot of sanding drums, you'll need a hell of a lot of these!

http://www.ebay.co.uk/itm/100pcs-1-2-x-1-2-80-Grit-Sanding-Drums-Bands-For-Dremel-Tools-/370679257885?pt=UK_Home_Garden_PowerTools_SM&hash=item564e349b1d

http://www.ebay.co.uk/itm/DREMEL-432-ROTARY-MULTI-TOOL-13MM-SANDING-DRUM-FINE-120-GRIT-PACK-OF-6-/190779452946?pt=UK_Home_Garden_PowerTools_SM&hash=item2c6b576e12

High speed cutters work well at 1/2 - 3/4 speed

Sanding drums work well at low speed, if you go too fast they'll rip apart prematurely.

Take your time and go steady. Get your gasket and put it up against the intake manifold and see how it matches up to that. Mine happened to fit perfectly to size against the manifold so I used it as a template for the throttle body to match it in size to the manifold, that's the important bit.

High speed cutters first for the heavy duty stuff, then sanding drums once you're trying to smooth it out evenly and carefully, start at lower grit (rough) and work your way to finer sanding material (higher grit). Once you're happy get the polishing wheel and knock yourself out with some metal polishing cream.

Make sure you don't widen your throttle body past the size of the intake manifold, otherwise you'll be creating a restriction and you'll end up having to port the intake manifold too.

Most important thing to remember is you can easily take material away but you can't put it back once you've shaven it off! So cut, measure, check, cut, measure, check, etc.








Offline blueandy

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Re: talk to me about widening the inlet?
« Reply #8 on: 19 March 2013, 15:28 »
thanks Khare, I'm only in Canford cliffs so I may just rock up and nick your one ;)