Ducati.ms - The Ultimate Ducati Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
I am building an engine from boxes of partial Ducati engines in my shop. End goal is just basic engine for daily riding. I have a bunch of bare W heads and I'd like to know if they can be modified to take the bigger V2 valve seats and valves? I'm not worrying about valve chamber size and shape, but I'm pretty sure just a bit bigger valve would a bit better if it is just simple machining for the valve seat. I have a full machine shop available, my company overhauls piston aircraft engines.
 

·
Registered
Joined
·
4,679 Posts
Yes, but you might have to unshroud the area around the new, bigger intake valve.

To be honest, I like the small valve engine in my Monster for everyday riding better than the big valve engine in my SS. It's just a smoother, more enjoyable ride...I thought I might notice a performance drop after I changed out the engine...but I didn't. The Monster is a much more pleasant bike around town. Not as herky-jerky at slower speeds.

Of course, the different cams make a difference too...
 

·
Registered
Joined
·
4 Posts
Discussion Starter #3
I am wondering if the small valves are a good choice for daily riding, also. I have a couple of partial 750SS engines I can rob valves and cams from to make a later 900 Monster head. The engine will go in a CR with the non-adjustable forks and narrower rear tire. I have a ton of parts, but mostly the "B" side, not preferred for performance parts. Hmmm...
 

·
Premium Member
Joined
·
3,699 Posts
IMHO not worth the effort, it has been done but gains are not big enough unless you want to do it for the challenge. You are looking at a few Hp difference between heads so I would try and gain the extra ponies with bigger pistons or higher compression instead. The elefants used the same heads to help them run cooler I have been told. I have done 944 kits with the small valve heads and the gains (percentage) are the same as big valve just a less amount.
 

·
Registered
Joined
·
6,132 Posts
I’d port the small valve heads along with a performance valve job and polish the valves to reduce carbon build up. You then have a head that flows better but with higher velocity.
 
1 - 5 of 5 Posts
Top