[DeTomaso] Rocker installation

[Henrik Svensson]

Hi

 

Ok, I'll start by fitting adjustable rods and measure the movement over the valve stems for different length and hope I can get it right. Otherwise I'll talk to AFD and see if they have any input why this occurs in my case. 

 

Thanks all for your input!

 

Henrik

 

Från: JDeRyke at aol.com [mailto:JDeRyke at aol.com] 
Skickat: den 18 maj 2010 08:37
Till: Henrik Svensson; detomaso at realbig.com
Ämne: Re: SV: [DeTomaso] Rocker installation

 

In a message dated 5/17/10 11:01:02 AM, hsv at traen.se writes:




Then I'm on the right track when looking at adjusting the rods, I guess that's the only part that is possible to adjust to get that kind of change?
I was told there are some kind of "hat" to place on top of the valve to get a bigger surface for the roller? Anything you recommend or not?



An adjustment of sorts can be done by shortening or lengthening the valve stems, but that introduces two new problems. First, you don't yet know whether the stems are too long or too short, so its possible to guess wrong and make things worse. Scond, if the valve stems are shortened much, it afftects the spring strength so the spring shims must be changed-or, possibly the entire spring assembly. And if the tip is too short relative to the spring retainer, its possible to generate an interference that unlateches the keepers and drops the valve into the cylinder. Total destruction follows milliseconds later.. 
The 'hat' you're speaking of is a hardened valve stem-cap which fits over the valve stem tips above the retainer and effectively lengthens the stem by 0.060" or so. They are only held in place by frictiion, so any valve float and they pop right back out. But again, right now you don't know which way to 'adjust' anything. Check first. With your aftermarket heads, valves and rockers you are essentially redesigning the whole top end of your motor, and such things take care and massaging to make them work correctly. Your parts are better than stock but are almost never drop-in replacements. Good luck- J Deryke