The B20VTEC discussion thread

[ZeForce]

You should really round off the egdes on the pistons, those sharp edges promote detonation

[bennjamin]

You should really round off the egdes on the pistons, those sharp edges promote detonation

id say this was a work in progress pic and not the final product.

But , a good heads up for all those learning !

[tinkerbell]

You should really round off the egdes on the pistons, those sharp edges promote detonation

yes, you really should (remember to take pictures after you finish rounding off the edges!)

[tinkerbell]

actually , post #281 has finished pics

[ZeForce]

[Lerlo]

oh, and see how the P3F is has a pronounced dish and the PHK is more flat?

that is the difference between the B20B3 and the B20B8

So the P3F is the one with 8.8 compression?

[tinkerbell]

yeah that's right.

[kraiye]

btw, how did you know how deep to go with the dremel? and what head/grinding bit did u use with it?

[TODA AU]

btw, how did you know how deep to go with the dremel?

A standard B20 intake valve has a head diameter of 31mm
But the B16A/B18C intake valve is 2mm bigger at 33mm.
So, the intake flycut radius aught to be increased by 1mm.

I wouldn't recommend going much deeper...

For interest sake, nothing need be done on the exhaust side as the standard exhaust valve sizes are the same for B16A/B18C/B20B @ 28mm (dia)

[tinkerbell]

yeah, so you don't just make them deeper as such, you take them wider (1mm) and correspondingly deeper...

[kraiye]

great info thanks.

don't suppose you know what's required for skunk2 pro1 cams in a b16with stock valves? would that require going too deep adrian?

[tinkerbell]

wat?

you wann run SK2 Pro cam's with stock B20B pistons?

i doubt that 'combination' will be any good...