<VV> OIL

[Ray]

Also consider the more aggressive ramps often found on a solid tappet cam as a difference. 


RCS



On Jan 6, 2012, at 10:05 PM, Frank DuVal <corvairduval at cox.net> wrote:

> I agree, hydraulic or solid, the same pressure is exerted on the cam.
> 
> Maybe lzdick meant roller cam?
> 
> Frank DuVal
> 
> On 1/6/2012 4:10 PM, Mark Durham wrote:
>> Seth, it does not matter if a engine is hydraulic or not. The core
>> issue is the amount of pressure on the cam to lifter faces caused by
>> spring pressure at the valves. The pressure was mitigated when the
>> engine designers went to roller cams.
>> The only difference between a solid lifter and hydraulic is the
>> hydraulic lifter automatically adjusts for wear on each revolution of
>> the cam. solid lifters need manual adjustment. So both would need zddp
>> to bring the levels to what was needed for the engine design.
>> Mark Durham
>> 
>> Sent from my Windows Phone
>> From: Sethracer at aol.com
>> Sent: 1/6/2012 10:02
>> To: lzdick at comcast.net; virtualvairs at corvair.org
>> Subject: Re:<VV>  OIL
>> Rich - Virtually all Corvair use Hydraulic lifters. Part of your reference
>> note says there in no need for it in Hydraulic-lifter motors. Why are folks
>>  worrying about the ZDDP amounts, if it isn't needed? Or is it just as
>> important  because we are talking about the lifter to cam lobe face contact,
>> which is  almost the same with a Hydraulic vs. solid-lifter set-up. I can
>> understand that  it is not-needed in a roller-cam motor. Any thoughts?
>> 
>> -Seth Emerson
>> 
>> 
>> 
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