I did not know JS's roller rocker came in other ratios. That is good to
know. Thanks for the correction. I was misinformed.
I agree completely. It depends on what you want to do with the engine.
I am building a street engine. I'm not interested in tearing it down
every 1000 miles or whatever.
On Bob Lang's advice -- he almost had to hold a gun to my head and say
read my lips :-) -- I kept the valve lift under .425 so I could use
stock dual coil TR6 valve springs.
I also stayed with Bob Lang's advice to stay close to 270 duration. I
ended up with 274. His advice has been confirmed from other sources. I
went with the stage II cast iron billet cam from Integral cams. I went
with a cast iron billet rather than a regrind because I wanted to use a
large base circle. Kastner recommends a large base circle. I don't know
if my cam has a fast lift curve as Kastner recommends. The cam was
modified from catalog specs to use 1.55:1 Roller Rockers from Ted.
Integral makes cams for Kent Prather. Figured I couldn't go wrong if
Kent Prather uses them.
http://www.integralcams.com/tr-250_tr-6.htm
So it depends on what you want to do with the engine. I would do things
much differently if this were a race engine. My engine will not win any
races. I will be happy with 140 HP and dependability. It's a 3000
mi/year sunny day car.
Don Malling
Greg Dito wrote:
> JS will provide roller rockers in any ratio desired. As Don, says, though,
the increased lift is but one small part of a properly tuned modified
engine.
Consideration should start with what an owner wants out of the engine,
planned budget, leading to cam selection and on from there.
The wilder the cam the more mods are needed to work with it
(valvetrain, induction, exhaust) in order to maximize the cam's potential
and deal with added internal stresses.
>
> Although I've not seen any comments to this effect, I wonder just
what rocker ratio is really necessary to maximize power from a stock
motor.
While the logic of "more is better" is often applied I would think that at
some point much more stress and wear is placed on the valvetrain with
diminishing return on power.
>
> Greg Dito
>
>>From: Don Malling <dmallin@attglobal.net>
>>Date: 2003/12/23 Tue AM 09:36:18 EST
>>To: 6pack@autox.team.net
>>Subject: Re: roller rockers
>>
>>I agree.
>>
>>I believe JS's roller rockers are 1.85:1 and as such should only be used
>>with a stock cam.
>>
>>While I'm no expert, from everything I read and hear (Vizard, Kastner,
>>Burgess and others) there's lots more to performance than increasing the
>>lift on a stock cam.
>>
>>
>>Don Malling
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