Cylinder head coolant ring

[Jamo]

http://www.s2forum.com/forum/showthread.php?t=44706

[Thuppu]

And it's a water jacket

How deep and wide should the groove be? Is 5x5mm enough? Does it work good enough on the head only, or should it be on the block also?

[Billman]

I think it a nice feature if you are going to remove the head and wanna run things to the limit. Personally would not remove the head but I would make it to the spare one.

It a nice add on and one can use this without any disadvantages.

[Jamo]

Yeah I first heard of this AFTER I finished building my car 6 months later

I suppose it all depends how you want to go and if I'm prepared to take it all apart again, undecided

[SteveH]

The Audi works cars ran this mod. The gains in cooling allow you to be more aggressive with timing as Jamo mentions. You can get the machining done for £150 if you look around. Doing the head and block would be a good idea, but it does mean ripping the engine out and dismantling to achieve this.
I have an unused 3B block that is screaming to have this done.

[G60Rallye]

The idea is to get more cooling through the head to reduce any chance of the head warping. More power should be available as you should be able to add some more ignition timing. Yes you just run the standard gasket Jamo.

[andy10v]

Is this to improve cooling overall, or more even cooling reducing hotspots?

[terrybullwon]

Can you still use the stock head gasket?

Yes.

Give him a call.....

[spink]

I remember someone was selling a head on here for BIG money a few months back with this done to it,think he refered to it as a 'works urq' mod or similar.He was very cagey about it though and wouldnt provide pics when asked as it was a secret

[Jamo]

Can you still use the stock head gasket?

[Jamo]

Yep error Repo told me he got I think it was 50 bhp from this mod with the extra timing you can run

[Error404]

I was wondering the other day if it was worth doing the block aswell?

[terrybullwon]

The very same he can do the block as well

[Error404]

AFAIK when I asked him about it a while back it was about £200 if done at the same time as getting the head resurfaced

[AndyP]

I've always known it as 'deck cooling' and JP can do it, not sure of cost though.