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Model specific boards => Golf mk3 => Topic started by: Foreveryoungaus16v on 25 March 2013, 20:49

Title: POLISH AND PORTING THROTTLE BODY
Post by: Foreveryoungaus16v on 25 March 2013, 20:49
Anyone know of a good place I could send my throttle body to get polished and ported?  Don't mind paying a

bit extra for a propper job. 
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Len on 26 March 2013, 16:26
As far as I know everybody has done their own.
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Foreveryoungaus16v on 26 March 2013, 17:51
Who is the expert on here that can do a good job?   :smiley:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Callum_K on 26 March 2013, 21:03
Buy a spare and have a go yourself, its pretty easy really....
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Len on 27 March 2013, 13:19
Buy a spare and have a go yourself, its pretty easy really....

Thats what I did but because of a broken sensor! :grin:

I used some round metal files, others have used dremel type tools, both with a hand finish with emery paper.
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Khare on 27 March 2013, 13:25
I've tried both files and dremmel, and with a dremmel it's quicker, easier and leaves a better finish.
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Gal on 27 March 2013, 14:45
Pics of what to remove?
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: tweed on 27 March 2013, 15:01
After dremmel I get the metal polish out and a rag and use good old bit of elbow Greece to get almost mirror finish
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: whileoceanasleeps on 27 March 2013, 15:19
After dremmel I get the metal polish out and a rag and use good old bit of elbow Greece to get almost mirror finish

elbow greece from ancient grease?  :grin:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Foreveryoungaus16v on 27 March 2013, 15:34
I would just rather pay someone to do a good job for me :smiley:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: spikenipple on 27 March 2013, 15:34
If someone can provide a decent set of pictures showing before/after, I will happily port it out and polish it for you on my lathe.
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: blueandy on 28 March 2013, 11:15
http://www.golfgtiforum.co.uk/index.php?topic=250621.msg2300483#msg2300483
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: spikenipple on 28 March 2013, 11:27
Cracking, fire us a PM then foreveryoungaus16v! If you send it my way, I'd appreciate it if you could measure the manifold port size so I can match them up, preferably with vernier calipers or something accurate  :smiley:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Foreveryoungaus16v on 28 March 2013, 12:36
Sent you PM my friend :smiley:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: VW BUSH on 28 March 2013, 19:53
On an 8v as you can only skim out so much on the lathe before it undercuts on the top side while you still have some step at the bottom.
By the time you have clocked it true on your face plate you could have dremmeled it :smiley:
Buy some Carbide burrs (not cheap) as they will cut it very cleanly and quickly and stay sharp for years if used on ali.
Dont drop them or press too hard as they will break.

http://www.ebay.co.uk/itm/10-Piece-Tungsten-Carbide-Burr-Set-3mm-3mm-shank-10-3x3-/360623128658?_trksid=p2047675.m1850&_trkparms=aid%3D222002%26algo%3DSIC.FIT%26ao%3D1%26asc%3D11%26meid%3D6568693252580083354%26pid%3D100011%26prg%3D1005%26rk%3D5%26sd%3D160968467775%26

If your up for making new vanes (Tricky) you can take it out a bit bigger and blend the step right out on a lathe :wink:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Leroy on 30 March 2013, 11:22
If someone can provide a decent set of pictures showing before/after, I will happily port it out and polish it for you on my lathe.

You could make a tidy profit doing these SpikeNipple, i want mine doing but haven't got the balls to do it myself!
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: spikenipple on 30 March 2013, 11:30
If you need yours doing too then drop me a PM. I'll probably take mine off later and measure it all up so I can produce some definitive drawings  :wink:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Leroy on 30 March 2013, 11:39
I'll get a spare and get back to you, cheers buddy!!!
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: murraymint on 30 March 2013, 12:48
I have a spare I wouldn't mind sending off to get done  :cool:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: spikenipple on 30 March 2013, 13:57
Drop me a PM buddy!
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Foreveryoungaus16v on 30 March 2013, 14:31
I think i have started off a good little earner for u :grin:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: spikenipple on 30 March 2013, 15:10
Haha you could be right! Can you suggest how much you'd be happy to pay? And no I won't accept Mars Bars or Grandmas   :laugh:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: tweed on 30 March 2013, 16:51
I'll do it for a grandma as long as she takes her teeth out.
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: spikenipple on 30 March 2013, 16:55
She might even let you polish her port  :lipsrsealed:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: blueandy on 30 March 2013, 18:16
Guys to just inject a little bit of realism to the thread,

Shirley you need to mark the porting on your own throttle bodies because there could well be casting differences and if you pull too much material out then you merely create a step again in the other direction?

To get a good match they need to be marked up for you to shave...
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: spikenipple on 30 March 2013, 18:19
I would have thought that the inlet manifold port is machined to size.
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Ess_Three on 30 March 2013, 20:39
I would have thought that the inlet manifold port is machined to size.

It is...and it's larger than you can get the TB casting, so no need for concern.

Just to remind people...opening up the TB will only give 1-2 BHP if you are lucky, on a standard engine...and go too far, and it'll kangaroo in traffic. That's from experience.
The ramps are there for a reason - to speed up airflow and make it more progressive at small openings...remove them and you lose the smooth transition from closed to part open throttle.
Just removing the ramps is usually OK with little by way of negative effects...but re-profile the casting and you can get kangarooing, with absolutely no gain in power.

I'll say that again: there is NO gain over simply removing the ramps, and that's on a 195+ BHP 16v.

So, by all means do it...just understand the downsides, and don't go expecting miracles.
 

If anyone is opening it up in a lathe, you'll need a 4 jaw, as the casting is offset.

Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: VW BUSH on 30 March 2013, 22:08
I would have thought that the inlet manifold port is machined to size.

It is...and it's larger than you can get the TB casting, so no need for concern.

Just to remind people...opening up the TB will only give 1-2 BHP if you are lucky, on a standard engine...and go too far, and it'll kangaroo in traffic. That's from experience.
The ramps are there for a reason - to speed up airflow and make it more progressive at small openings...remove them and you lose the smooth transition from closed to part open throttle.
Just removing the ramps is usually OK with little by way of negative effects...but re-profile the casting and you can get kangarooing, with absolutely no gain in power.

I'll say that again: there is NO gain over simply removing the ramps, and that's on a 195+ BHP 16v.

So, by all means do it...just understand the downsides, and don't go expecting miracles.
 

If anyone is opening it up in a lathe, you'll need a 4 jaw, as the casting is offset.

As I said earlier best on a face plate over a 4 jaw as you will probably need to shim it to get it running true and its easier to hold, done it loads f**ked a few up in the process :lipsrsealed:
You are right it is has a an offset :smiley:

Not so sure on the purpose of the ramp, I will say that the step enables an easier tidy shut off between the two cores in the mould, its how I would build it.
You are right in saying it would speed the air up so I. am sitting on the fence.


Guys to just inject a little bit of realism to the thread,

Surely you need to mark the porting on your own throttle bodies because there could well be casting differences and if you pull too much material out then you merely create a step again in the other direction?

To get a good match they need to be marked up for you to shave...

As I mentioned if you get it wrong on a lathe you will create an undercut opposite the original step, need to clock the bore and mark the cutting surface so you can see where its cutting.
Bore is pretty good but flanges run out a little hence face plate and shim mentioned above.
Some types need an angle plate so you can get in on the compound slide from the back

I have a shelf full of TB's and MAF housings which I have mullered over the years, I used to do a practice one before I took on paying work....

Butterfly must come out when working it on a lathe, also the mechanism and wheel off the side.
Also be aware that you may hit some porosity, also cutting speed will need to be right as you will get a rough finish.....

By all means have a go, the 8v and VR are about the easiest to do and KR the hardest on golfs.

I made a fortune on Fiesta Zetec's as they are pretty restrictive and the Mazda large body TB's are like gold dust and twice the price.
There is a hole in the ceiling tiles above my old workshop where one did a flyer :lipsrsealed:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Foreveryoungaus16v on 31 March 2013, 21:00
Sounds very tricky :shocked:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: thai-wronghorse on 31 March 2013, 21:23
Infact it sounds like far too much hassle attempting to put it on a lathe for negligible gains. Dremel will suffice in this instance.
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: spikenipple on 31 March 2013, 23:10
Admittedly I know nothing of the advantages/disadvantages of porting the throttle body, but when it comes to the setup on a lathe I'm sure it won't be a problem (thanks for the tips Ess_Three & VW BUSH  :smiley:). It's a case of time vs money vs effort and I'm fortunate enough to have access to the equipment to get the job done.
I'm going to lighten and balance a spare flywheel on Tuesday too  :cool:
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: Len on 03 April 2013, 12:42
I'm going to lighten and balance a spare flywheel on Tuesday too  :cool:

Do one for me! pretty please! :grin:
Where in Wilshire are you?
Title: Re: POLISH AND PORTING THROTTLE BODY
Post by: spikenipple on 03 April 2013, 17:28
Trowbridge, unfortunately  :grin:
I haven't started modifying my flywheel yet, as I'm halfway through making the balancing arbor for it. Once I've finished mine I'll give you a shout  :smiley: