MustangWorks.com : Ford Forums - View Single Post - AFR 185's w/E-303: Piston to valve clearance problems?

Technick · 03-29-2003, 06:06 PM

The only time that is true is if you have a 1986 5.0. The 86 5.0 had NO valve reliefs at all. 87 and up come with a valve relief already, not much of one but enough. I have installed AFR 205, Edelbrock Perf. RPM, Trick Flow Twisted Wedge, Holley Systemax, Ford Motorsport X and Y heads, Dart heads ALL on stock short block 5.0's of 87' vintage or newer, and with a variety of cam's that as long as the duration @ .050 is NO MORE than 230 degree's then you WILL NOT have a problem! Period! You see with the shorter duration cams (less that 230 deg.) the valve is simply NOT OPEN anywhere near the piston during operation. At least not near enough to be a problem on a Hyd. Roller engine that does not see over 6,300 rpm.

03-29-2003, 06:06 PM	#6
Technick Registered Member Join Date: Feb 2003 Location: Seattle, Wa. Posts: 175	The only time that is true is if you have a 1986 5.0. The 86 5.0 had NO valve reliefs at all. 87 and up come with a valve relief already, not much of one but enough. I have installed AFR 205, Edelbrock Perf. RPM, Trick Flow Twisted Wedge, Holley Systemax, Ford Motorsport X and Y heads, Dart heads ALL on stock short block 5.0's of 87' vintage or newer, and with a variety of cam's that as long as the duration @ .050 is NO MORE than 230 degree's then you WILL NOT have a problem! Period! You see with the shorter duration cams (less that 230 deg.) the valve is simply NOT OPEN anywhere near the piston during operation. At least not near enough to be a problem on a Hyd. Roller engine that does not see over 6,300 rpm. __________________ No matter how much you spend, or how much you prepare, there is ALWAYS someone else faster or quicker than YOU!!!!!!!!!!