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Model specific boards => Golf mk2 => Topic started by: Sgt_Lemon on 28 February 2014, 10:34

Title: Big valves
Post by: Sgt_Lemon on 28 February 2014, 10:34
Looked all over online and sifted through this forum. Currently porting a 8v head and have a 2.0l bottom end on its way. It says everywhere that bigger valves should unrestricted the bottom end but I want to know how it's done. The heads is going in for a 3 angled seat, a skim and new valve guides but are there any exhaust valves that can be put in without messing with the valve seat position?
Any advice wanted really.
Title: Re: Big valves
Post by: gazareth on 28 February 2014, 18:05
orite sarge what power output are you aiming for with this engine? the big exhaust valve is meant to give good gains on the 2 litre block but its supposed to be pretty darn pricey to have them done.
Title: Re: Big valves
Post by: Sgt_Lemon on 28 February 2014, 18:49
Well I wanted 150ish bhp 145ish torque but just didn't want a massive restriction. Was wondering with a 35mm exhaust valve if it's possible just to port the exhaust enough to fit it in without moving the valve seat. Probably optimistic with what figures I want but you have to aim high and it's my first real project with the work done by myself.
Title: Re: Big valves
Post by: Diamond Hell on 28 February 2014, 19:17
Are you planning on doing the porting yourself, or having it done professionally?

A professional outfit should work with you to deliver what you want, so would be able to advise where to source bigger valves, if required.
Title: Re: Big valves
Post by: Sgt_Lemon on 28 February 2014, 19:33
The porting was going to be done myself, everything else was going to a professional. I have spoke to him on the phone but he doesn't specialise in vw but is a really good engineer, once I know what I need then I will go and speak to him more in depth to work it all out.

I just can't justify a crazy price tag for new seats just wanted to know the biggest valves possible without seat work. Read on club gti that a 34mm exhaust may fit in those seats along with 40.5mm inlet but won't bother on the inlet.

It is supposed to be a cheapish project to keep me going until I can afford the next car but want to maximise what's reasonably possible on the head without going to extremes
Title: Re: Big valves
Post by: clipperjay on 28 February 2014, 19:57
Are you planning on doing the porting yourself, or having it done professionally?

A professional outfit should work with you to deliver what you want, so would be able to advise where to source bigger valves, if required.

This Dude!