Hi guys, just brought this pukka head, it looks the bees nees and was done by holbans engineering a few years ago but wasnt used, its got 43mm inlet and 38mm exhaust stainless valves, ported and gasflowed inlet and exhaust ports, the throats are real nice, 3 angle valve seats cut, heres a few pictures, what do you think?

 

 

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sorry about the other pictures had trouble uploading, what do you think?

cheers daz

 

i think you should give it to me

 

Very nice, i remember when i got mine back from being done, didnt want to fit it just wanted to put it on a shelf in my house!

 

Furniture 

 

yeah its pure art, what you reckon to the ports? look really well done to me

 

Looks ok but the valve guides have not been flushed which is the first thing done to any good CVH head when improving flow, cant really make much else out becuase the photo's are out of focus.

 

yeah the valve guides havent been done , yeah sorry camera aint all tht good,

 

also i was told the inlet side had wasted stem on the back of the valve, any ideas what that is?

 

Wasted Stem? No idea mate lol

 

mines a specialised engines one pretty similar spec. nice!

 

The inlet guides don't look too bad, as they have been tapered quite well, in fact i wish i had left my exhaust guides standard length.

The inlet port looks like its mirror polished, if so thats not particularly good.

Wasted stem, could be the valve stem has been machined down slightly.

The head looks clean, but i couldn't tell you much from those photos

Rob,

 

yeah ive read up on the wasted stem its the inlet valve thats been machined , spot on rob, lol, the inlets are not mirror thats the light stupid camera, there same as exhaust ports, so not a bad head then? Im really chuffed with it,

 

il get some better pictures with my better cam after work tonight,

 

Good stuff, now get it fitted

 

Better pics sure would help.
Inlet ports should not be smooth - not sure if they are or not. If they are too smooth it is easy to roughen up the surface finish.
The CVH valve guides are very long as stock, and can be reduced in length so they are flush with the port. (This alone is worth much more than you would think)

Wasted stem is the reduced diameter valve stems near the valve head. The Burtons valves have this feature.

Other than that cant tell you much more

Cheers!!

 

should i get a bit of wet and dry 1200 and rough them up a bit then , as they are a bit smooth, cheers daz

 

More like 80-120 grit on the inlet side.

Rob,

 

why do the inlet ports need to be rough , sorry for sounding thick lol,

cheers daz

 

Its okay mate, every one needs to ask questions!

A polished port promotes wall wetting, which is when fuel vapour comes out of the air/fuel mixture and sticks to the wall. Slightly rough walls stop this... Thats why it doesn't matter on the exhaust side.

Not a big problem when the injector is right on the back of the valve like a lot of modern engines.

Rob,

 

aww i see, il get some 120 grit wet and dry and do it tommorow at work so just generally rough them up, obviously not to much to mess around with port shape, got so much to do , cars a shell atm, just done the whole underside, stonechiped and topcoated radiant red , all powder coated, braided fuel and brake lines throughout, il get a resto thread going soon, cheers for the help rob mate much appreciated,

cheers daz

 

thats one way to get a higher post count lol

Looks nice mate get it fitted asap

 

another from essex i see

 

yes im from colchester area, been browsing for a while, need to get a resto thread going asap

 

No worries mate, no need to go crazy with the sanding, and only on the inlet side.

 

ive got a head from cylinder head developments and its very similar to yours but the valves guides are flush and the inlet ports aint as smooth as urs and it makes very good power and is so noticably different

its a good investment