Cam timing and domed pistons

[scampbel98]

I've been reading a bunch in the threads about engine builds, cam timing, adjustable cam pulleys and the like.
What's unclear yet are a few things:
1) How much adjustment is there in intake and exhaust timing (degrees)
2) If using 8mm domed pistons - is there danger of piston|valve contact with the amount of cam adjustment possible?
3) What's the best resource to read on setting up cam/crank timing? Guy Crofts blogs?
4) Do larger valves increase tendency of piston\valve contact with cam adjustments? Are they worth it?
5) How do cam lifts factor into all this - it looks like cam lifts go from .385 to .497 or something like that...

Currently running a 1.8L block, 8mm domes, 2L FI head, stock cams, 4:2:1 . Runs good but could be better I think.
Planning to build up another head. it's easy enough to swap right ?

[vandor]

1) How much adjustment is there in intake and exhaust timing (degrees)

Usually more than you need

2) If using 8mm domed pistons - is there danger of piston|valve contact with the amount of cam adjustment possible?

Yes, but this also depends on the cams.

3) What's the best resource to read on setting up cam/crank timing? Guy Crofts blogs?

Guy's books.

4) Do larger valves increase tendency of piston\valve contact with cam adjustments? Are they worth it?

Yes and it depends. Possibly not worth it if you are running stock cams.

5) How do cam lifts factor into all this - it looks like cam lifts go from .385 to .497 or something like that...

More lift = more chance you'll hit the piston It is best to dry build the engine to check valve to piston clearance at different cam timing settings. It's not enough to check at TDC, as clearance may decrease as the crank rotates (valve opens faster than the piston is moving down).

[Daniel]

We have had plenty of talk on the subject here in this forum a search would find something on the topic.

[engineerted]

Vandor is correct, it depends on a lot of factors. The dome itseft is not the problem it is the valve pockets in the pistons. You do know in cylinders 1&4 the valves are not centered in the chamber but the piston valve cut outs are so you will have even less clearance in those cylinders. There is some good articals about this on guy's site and some of the other forums.

Just be carefull and know what your limits are when adjusting the cam pullies.