Installing valve seats

[André_82]

Hi Guys,

i need some help, i would like to install new / bigger valve seats in my 041 casting vw heads but unfortunately i don´t now the right oversize for the fit of the seat. What oversize is the best for a hot type 1 vw engine? 

Cheers Andre

[besserwisser]

First of all you already have 39mm in a basicly standard head. Valveseats for bigger valves than 40 is a tight fit next to the sparkplug. The press fit I use is 0.15mm oversize on the seat. I use a bronze alloy called jm7 which expands as much as the alu in the head therefore never a lost seat. Unless you are intending to do some serious racing I think you can port the 041 head with the 39 intake to a good performance head. I get 100hp out of a low compression 1680 with 35.5intake valve.