Been poking around the parts catalogue and found something labelled as "oversize valves" for both exhaust and inlet. Assuming these are non-standard, they also appear to be cheaper than the standard one's if still available via skoda. Just wondering what advantages or disadvantages oversized valves give. (My completely uneducated guess is oversize exhaust valves are probably more useful than inlet).

I have a spare cylinder head from a 135, and was thinking of cleaning it up some time and messing with it so long as the tools needed to sort out the valve springs aren't too expensive. From what I can tell the 136 uses different outer valve springs and lower support washers, and the 135 has an inner spring base that the 136 doesn't have. I am assuming the actual cylinder head block for the 135 is the same as the 136 - but if I could simply transplant it onto a 136 set-up then mayaswell just scrape the remaining gasket off and clean it up.

With larger ports, larger valves will:-

Pro - give higher peak gas flow, allowing higher peak power.

Con - reduce gas velocity at low revs, leading to potential problems of poor scavenging, and fuel dropping out of suspension in the air, leading to poor running and pickup.

the 136 has better flow pattens.

i'm pretty sure the 136 can be bolted on in place of the 135 head.

the 136 has better flow pattens.

i'm pretty sure the 136 can be bolted on in place of the 135 head.

i sure hope so, for tomorrow i will attempt to put a favorit head on a rapid block and i'm very concerned about waterways!

Compare the holes in the gasket with the ways in the block and head.

Compare the holes.

yes... every friday night.