multi angle head ?

[matt1334]

hi, i have just been looking through the reciepts for my car and its had some head work done mulit angle, so can someone explain what this is and whats the purpose thx

[Sparkie]

its where the valve touches the valve seat.

the seat is ground at 30deg, 45deg and 60deg. with the valve touching the 45deg one.

the gas flow past the angled area is better than if it where just a straight 45deg angle, cos the actual contact area with the valve is smaller than a non-multi angled valve seat.

hence as it the valve opens it allow more gas to get past, more quickly, than standard.

im sure it might alter the swirl pattern of the inlet charge to, but dont quote me on that. :laugh:

[Trevhib]

im sure it might alter the swirl pattern of the inlet charge to, but dont quote me on that. :laugh:

Too late, I told a load of people what you've been saying. :tuttut: