hi compressions

[dzorde at aesprodata.com.au]

     My understanding has always been that the valve spins to promote even 
     seat wear and to avoid the valve sticking due to constant hammering on 
     the same spots.
     
     Dan        dzorde at aesprodata.com.au


______________________________ Reply Separator _________________________________
Subject: re: Re: hi compressions
Author:  diy_efi at coulomb.eng.ohio-state.edu at INTERNET
Date:    9/10/96 8:15 AM


     
On Mon, 9 Sep 1996 SRavet at bangate.compaq.com wrote:
     
> 
> You could spline a single shaft to keep it from spinning also.  But, valves 
> rotate now by design, right?  Why, and what would happen to an oddly shaped 
> valve that couldn't rotate?
> 
> --steve
> 
     
Well there are a few engines out there that have valves that DON'T 
rotate.  These are the old Boss engines from Ford (302,351 and the 429). 
These valves are held in place by keepers that pinch the valve stem (ie 
the keepers don't butt against eachother).  The result are valves and valve 
seats that don't last as long but the pay off is less risk of dropping a 
valve at high RPM.  My Boss 351 is set up like this, I just had the heads 
redone and the exhaust valves had to be replaced because of this. (or so 
my machinist told me...he seems very trustworthy) 
Just my two cents...(and my first post to this list!) 
cheers everyone...
james