M20 Porting Question

[redlightpete]

I know the general guideline is to not blindly attempt to port an 885 head, but I still have to ask. On the head I'm working on, on the short side of the ports, there's a corner where machined section meets the casting, and another where the seat meets the port. Would it be useful to round off these edges, or am I more likely to make things worse?

[TobyB]

If you simply radius them, you won't hurt anything. But you probably won't gain 10 bhp, either-

That's what the red paint on the valve cover is for.

t

[SkiFree]

Historically speaking, rounding off that edge is a nice touch. As Toby says, it's no red valve cover, but it's not a bad thing either.

[E30DriftMissile]

M20 Porting Question

Don't mean to thread Jack but if you deck the head does that effect tdc and cam timing?
Edited*

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[SkiFree]

Clarify what "tac timing" is and we might be able to help.

Cam timing: Yes

[E30DriftMissile]

I decked my head and lightly shaved the block and at tdc I was really hard to turn the crank so I backed off


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[digger]

if the cam axis and crank axis change then yes the cam timing moves a bit. how much was it decked?