Vts Head. exhaust ports

[spencer_cammedvts]

Hi all.

my head cracked recently and have had to scrap it. due to this i have bought another head and am currently in the process of porting it in my garage.

I took the valves out and started Flowing the inlet ports. When i took the exhaust valves out i noticed that they are different to my previous head. these ports have holes in! if you flip the head upside down and look down towards the valve guides there is a 4/5mm hole drilled into each port between the valve seat and the valve guide! is this supposed to be there? what is the purpose of it?

please let me know chaps!

All the best,
Dan

[spencer_cammedvts]

could it be something to do with the egr valve? im sure there isnt one on the head but doesnt the egr valve take the exhaust gases and put them back into the intake? something to do with better emissions i think?

[Mystic]

Im probably just repeating stuff you already know but the mk2 head was re-designed to allow better gas flow so i assume those holes are something to do with that?

[spencer_cammedvts]

ner i didnt know that mate. but didnt the mk 2's have the 2 prongues on the front?

[Toad]

They did have, yes. That was to hold part of the air injection pump to the face of the head.

No idea about the holes though mate.

[spencer_cammedvts]

im sure the egr valve was on the right hand side of the head and there is a channel through the head. ther hole that is in each exhaust port may be to take the exhaust gasses through to the egr valve then into the intake system?

[Toad]

Hmmm. For sure, the hole in the side of the head is on the right side. I've got mine covered up. I have some pictures of the BV head in my progress thread, but i don't remember seeing any holes. Here's a pic:

http://i13.tinypic.com/505yp74.jpg


I don't think you can see I'm afraid. Only the inlet side is really viewable properly. Where exactly are these holes then mate?

[spencer_cammedvts]

Hmmm. For sure, the hole in the side of the head is on the right side. I've got mine covered up. I have some pictures of the BV head in my progress thread, but i don't remember seeing any holes. Here's a pic:

http://i13.tinypic.com/505yp74.jpg


I don't think you can see I'm afraid. Only the inlet side is really viewable properly. Where exactly are these holes then mate?

its in between the valve guide and the actual valve seat. its the back side of the exhaust post that only bit of the exhaust ports that you cant see in the pics.

[Toad]

OK mate, gotcha. I don't have any pics of that area.

[spencer_cammedvts]

thats ok bud. does your head have the egr valve? im pretty sure thats what their for buddy

[Toad]

It did have yes mate, I said that earlier, lol. :)

[spencer_cammedvts]

oh yeah lol. actually i can se the start of one of the holes on the exhaust port to the top left. (obviously the one without the valve in it lol)

[Toad]

Ooh, I think I see it too actually.