Bead blasting heads
 

My heads are going for porting and valves guides etc,I have use of a bead blaster.Where is it safe to bead blast the heads ? all over or do I need to stay clear of the cam tower faces and barrel faces ?

I'm no expert but I'd definitely stay away from any of the sealing surfaces and obviously the insides.

We bead blast all our heads, (all areas) glass beads have a very low probability of metal removal, in other words it will not change the dimensions.

bead blast
 

We bead blast everything as well, just be sure that it is glass beads, and if you have a bit of gasket or some sealer on a machined area remove it instead of trying to blast a stubborn area for a long period.

Mike Bruns JBRacing.com

+1
To remove soft pliable material of the head, it's easier to use chemicals. Combustion chamber's carbon build up, it works great.

cheers guys degrease then in the blast cabinet tomorrow with a very fine bead

Uh, no. Degrease them with liquid degreaser first. Use blasting medium to remove foreign particles like carbon and surface corrosion.

Sherwood

Just be careful how you move them around in your cabinet... You do not want to put scratches in the surfaces from your cab. grate.

-Michael

Ok guys I will be careful but while I have your attention :)
I will be having a valve job and mild port carried out.I have Jenveys which taper from 48mm to 41mm would you open the 39mm inlets to 41mm or leave a step ?
BTW I have searched on here and read up on this but still cant decide which way to go

Blend
 

Mr P,

Blend them through, no question.

andy

Blend them, no question.
Anytime there's a transition step, you stand the strong possibility of fuel dropping out of the mixture and causing uneven fuel mixture distribution, especially at lower RPM's.