Heads/cam question
Thread Starter
Joined: Apr 2006
Posts: 3,899
Likes: 1,143
From: Grand Rapids, Michigan
Heads/cam question I've already decided on a custom cam for my engine this winter, Comp XE-R lobes - 226/230 @ .050, .581/.588 lift with 110 + 0 LSA. I figure if I am going to go through all the effort to do a cam, intake, and headers, I may as well get heads as well. I'm looking specifically at the PRC Stage 1.5 5.3L heads from Texas Speed. I've read multiple times that you have to flycut your pistons to run 5.3 heads due to reduced piston to valve clearance. My question is - with this small of a cam, will I even need to flycut? I didn't think so, but I'd like to be sure. I also plan on getting these with a 2.02 valves instead of 2.04 valves because I don't really think a 2.04 valve is justified on a stock cube engine that is only going to see 6200 RPM max. So if anyone can give me solid info on if this will work, I'd appreciate it.
Thread Starter
Joined: Apr 2006
Posts: 3,899
Likes: 1,143
From: Grand Rapids, Michigan
I must ask impossible questions because I never get answers - I always see similar threads with like 50 replies... help please, I'd really like to get a plan cemented so I can concentrate on other aspects of my build.
I think its because of the larger diameter valves that some people with large cams have to flycut. A 2.020 valve is only .010 larger radius, which puts it only like .003 deeper. It also depends on how deep the seats were cut and where the valve was hung, but it probably wont make a HUGE difference. If youre heads arent milled, you probably dont have to flycut with a cam that small. Measure for piece of mind though.
Originally Posted by GuitsBoy
I think its because of the larger diameter valves that some people with large cams have to fly cut. A 2.020 valve is only .010 larger radius, which puts it only like .003 deeper. It also depends on how deep the seats were cut and where the valve was hung, but it probably wont make a HUGE difference. If you're heads aren't milled, you probably dont have to flycut with a cam that small. Measure for piece of mind though.
and just call them they're a business and want the money i assure you, so if they have to take a few call to make a grand i don't see that as a problem. Plus they have great customer service, and I'm sure you could pm them on e here. 
