luxembourgrst

hy what do you tink about my cylinder head

3 seats valve (new exhaust valve how to know if they are with sodium? they have to be sodium?)




only the inlet ports looks ported






the exhaust one (why they didn't port them)




the head is skinned what kind of head was this (other numbers like my standard rst head they wrote carb on it was it a carburettor 1.6 head ?? )


I only gonna cut the inlet valve guide good idea of curse but only the inlet ones

J1mbo

iTrader: (1)

There is no need to open the exit of the exhaust port, the flat on the port is a possitive thing. Looks nice

haz87

They haven't even trimmed the valve guides. Looks like a very very very basic job, port matched inlet only by the looks of it.

Hope you didn't pay much for it

J1mbo

iTrader: (1)

Knocking back the guides shows that it's been done properly rather than just stick a cutter through it..

haz87

Appreciate what your saying Jimbo, but surely trimming them back is beneficial as its one less thing to interrupt air flow (yes i know the vale stem will still interrupt but its obviously less bulky than the guide itself)?

luxembourgrst

well yes normaly you take out the valve guide and work the ports an then put new one


I gonne cut them off the inlet valve good idea I heard about that it helps a lot because at this area the flow is very active

J1mbo

iTrader: (1)

The longer the guide the more support the valve has so it's good to keep them where possible.
Nick waples normally always leaves them in so I'm sure there are no negatives to having them in.
All personal opinion though

Canada1

The only negative is decreased air flow through the port. Sure if you want a little more valve support (but the valve guide is already very long and trimming the last bit sticking into the port will have no measured reduction in valve guide life).

After many hours on a Superflow 600 flow bench I can certainly tell you there is a large flow improvement removing the protruding guide. Measured 12 cfm increase at 10mm lift I recall.

luxembourgrst

well I cutted the inlet valve guide off