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> Roller cam, Whatsit?
Lavanaut
post Jul 11 2007, 03:12 PM
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Been reading all over the place about roller cams and their benefits. Though I've even seen pictures of 'em, I can't define exactly what makes them different, or why they allow for performance gains.

I *think* I understand that it's related to "more aggressive" cam lobe profiles..? (IMG:style_emoticons/default/idea.gif) Now if only I knew (IMG:style_emoticons/default/WTF.gif) "more aggressive" means when talking about cam lobes!

Would much appreciate a little clarification...

Thanks
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Chris Pincetich
post Jul 11 2007, 03:26 PM
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Jake Raby made some for TIV engines, but only his in-house custom builds (IMG:style_emoticons/default/sad.gif)

I'm no expert, but have been reading a lot about them and talked a bit with McMark....basically a normal cam is flat tapped and the ovalish lobe pushes on the flat lifters that move the valves. A roller cam is actually roller lifters...the cam looks normal. The lifters are not flatish where they ride on the camshaft, they have little wheels. This GREATLY reduces friction at the cam lifter interface (ever seen a photo of a worn out cam lobe?). The cam can then be ground more radically, so the valves can open and close faster, which is awesome for performance. So, roller cam is steeper sloped lobes and lifters that roll on the cam surface...it is the whole enchilada.

I want one (IMG:style_emoticons/default/beerchug.gif)
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davep
post Jul 11 2007, 03:36 PM
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http://forums.aircooledtechnology.com/showthread.php?t=212
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Joe Ricard
post Jul 11 2007, 03:36 PM
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Cam lobes do not look normal. the shape is WAY different. The ramp speeds are significantly faster. There is less friction too. SO if the engine is using less power to just turn itself over there will be more to push the car. and it does make more power also.
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Lavanaut
post Jul 11 2007, 03:37 PM
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Ahhh ok. That makes sense Chris, thanks. Yep, it's Jake's work I've been reading about while grappling constantly with the future of my teener, or the the acquisition of the one I don't yet own. The roller cam deveolpments just make the whole decision that much more "interesting". (IMG:style_emoticons/default/blink.gif)

(IMG:style_emoticons/default/beerchug.gif)
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Joe Ricard
post Jul 11 2007, 03:43 PM
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If you have LOTS of money it will still be tough to get an engine with roller cam technology.
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Lavanaut
post Jul 11 2007, 03:44 PM
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QUOTE(davep @ Jul 11 2007, 02:36 PM) *

http://forums.aircooledtechnology.com/showthread.php?t=212

Those are the exact pics I was talking about, thanks. What I glossed over the first time I saw them, but notice now (thanks Chris) is the roller itself as seen in the below pic (borrowed with respect from the above thread, hope you don't mind Jake) (IMG:style_emoticons/default/clap56.gif)

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Aaron Cox
post Jul 11 2007, 04:05 PM
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insane valve opening and closing speeds.....

if you can open and close the valve faster, you can have it open all the way for longer periods of time.....
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Jake Raby
post Jul 11 2007, 04:56 PM
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Funny this should pop up today as I am actually working on the final revision of our roller lifter tooling and have just finished a flawless bushing installation for some tests tomorrow...

I'll post some pics and provide a lengthy post on the benefits of roller cams in these engines. I will try to do this tonight-

We are working very hard to have all RAT Turnkey engines roller equipped by the end of March 2008, I had wanted this done by the end of 2007 but refinement of the parts, tooling and the vast amount of engine combination development we have to do is not making the date a possibility.

This is the most tedious development work i have ever done here to date, every part of it is critical and there are no margins of error during the design and fitting procedures.

The results are worth the effort, but it's not for the faint of heart.
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Lavanaut
post Jul 11 2007, 05:05 PM
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QUOTE(Jake Raby @ Jul 11 2007, 03:56 PM) *

I'll post some pics and provide a lengthy post on the benefits of roller cams in these engines. I will try to do this tonight-

I'll look forward to reading more when there's info to be consumed. Thanks for the reply, the future looks promising for the Type IV. (IMG:style_emoticons/default/boldblue.gif)
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Jake Raby
post Jul 11 2007, 05:57 PM
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Very promising. As long asI can keep my sanity and my health long enough to see it all through- place is driving me crazy lately!
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So.Cal.914
post Jul 11 2007, 06:03 PM
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If you aren't happy and healthy you ain't got shit, stop and smell the flowers Jake...

And maybe smoke a few. (IMG:style_emoticons/default/smoke.gif)
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Jake Raby
post Jul 11 2007, 06:09 PM
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QUOTE(So.Cal.914 @ Jul 11 2007, 05:03 PM) *

If you aren't happy and healthy you ain't got shit, stop and smell the flowers Jake...

And maybe smoke a few. (IMG:style_emoticons/default/smoke.gif)


I am plenty happy, hell I should be because we are on the verge of virtually revolutionizing the engine and getting to the point I have wanted to be fore 10 years. The issue is that its all coming together at once..

I have just about come to the conclusion that soon I will have to go into hiding for 3-4 months to get this all finished swiftly and correctly.

Slowing down isn't an option no matter what happens.
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Brando
post Jul 12 2007, 02:43 PM
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roller rocker technology... awesome. How long before you implement spherical valves? (IMG:style_emoticons/default/smile.gif)
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Jake Raby
post Jul 12 2007, 05:16 PM
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Roller LIFTERS- Not rockers. Adding a roller rocker does very little and doesn't open any doors to added performance.

I made a post in the R&D portion of my forum community last night, I'll do the same here tomorrow morning (been at the track testing all day and I am beat)
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Jake Raby
post Jul 13 2007, 08:31 AM
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Just a teaser :-)
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brer
post Jul 13 2007, 11:02 AM
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wow.
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Brando
post Jul 13 2007, 02:45 PM
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oooooh pretty. Why must you tease us so.. why?
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Jake Raby
post Jul 13 2007, 03:05 PM
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It's kinda like a bitch in tight jeans....
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SGB
post Jul 13 2007, 10:56 PM
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My mouth is haging open from those pictures...
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