[Mk2] [Turbo] Porting & Polishing

[Shmed]

Has anyone ported and polished their own head? I've got some 1mm oversize Ferrea's, and I believe I need to widen my throats to accomodate the new valves.

As I am about to embark on a winter engine build, I will soon have a spare head and am thinking of 'doing it myself'.

Would this set be enough, or should I stop being a skinflint and just pay a professional

http://www.motorsport-tools.com/index.p ... cts_id=844

[Slarty]

stop being a skinflint and just pay a professional

That'd be my opinion. Unless you have a flowbench to check the flow rates at each stage, you don't have any idea what you're doing to the head.

It might look right to the eye but that doesn't neccesarily mean that it is right in terms of flow.

[Shmed]

Yep, the voices in the back of my head say that too.

[sjm1984]

DIY you could ruin it and it be worth scrap

get a pro to do it.

Be warned P&P isn't as cheap as some think.

[JJ]

Where the 1mm oversized valve sits, you'll have to get that machined out.... Port polishing and polishing up the combustion face ( removing cast imperfections ) is easy and worth doing ....

I've got the combustion face of the head looking like the crowns of my forged pistons... shiney and smooth...

Just as a heads up... normally machine shops will charge anywhere around £25 per valve to machine cut and fit a new oversized valve seat !!

Check with a member on here called wingers ... He went down this route, he can advise accordingly....

[Driftlimits Performance]

but too shiney and smooth is a bad thing! so don't go toooo far!

[Shmed]

I think that I'll be getting someone who has a clue to get my 1mm oversized valves in. Anybody know of such a person? Preferably in the Midlands area, but a good job is more important than them being close.

Maybe I'll do my polishing myself, apparently, too smooth and petrol sticks to the head according to something I've read?!

[sjm1984]

I think that I'll be getting someone who has a clue to get my 1mm oversized valves in. Anybody know of such a person? Preferably in the Midlands area, but a good job is more important than them being close.

Maybe I'll do my polishing myself, apparently, too smooth and petrol sticks to the head according to something I've read?!

Centry motorsport

or

"banned trader

[Shmed]

Yeah, I was thinking banned trader would be a good bet. He's been giving me some decent advice so far!

[Century Motorsport]

I can help you on this if you like. And i'm not a baned trader

[Shmed]

I can help you on this if you like. And i'm not a baned trader

I'll drop you a pm

[mrdb]

with regards ti port finish you want a rough ish even finish on the inlet to help promote a slightly better air/fuel mix. the exhaust you want a mirror finish..

[Shmed]

All about generating turbulence on the way in right?

[anastasios]

im no expert on this.but here it goes,theres a reason golf balls are made like they have the pox
you need the little mountains inside your intake(except the molds casting marks),if im correct the little mountains produce underpressure thus minimizing intake wall drag of the incomming air.
i would skip P&P though,theres little gains out of our heads.

[Shmed]

Anyone know if valve spring and retainer sets that are designed for rev 3 will fit a rev 2 head?

Spec:
Outer Spring -- 27.50mm OD -- 20.00mm ID
Inner Spring -- 20.00mm OD -- 15.20mm ID
77 lbs seat pressure -- 77 lbs @ 35.50mm
14.00mm Max Net Lift
20.70mm Coil Bind
12.10 lbs/mm Rate

[anastasios]

you get better fuel atomization through mounting trumpets and putting your injectors at the begining of their inlet lip.
its your head and money, good luck with your build