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Roller cams....
https://slantsix.org/forum/viewtopic.php?t=39589		 Page 3 of 3
Author:  Shaker223 [ Mon Mar 29, 2010 4:57 pm ]
Post subject: 
To expensive for me! The cams we have now can out flow what the head is capable of supporting (even after porting). If wiping a cam was a real issue, I'd use a solid roller on a regular old flat tappet cam. I'd spend the money someplace else. JMO.
Author:  DusterIdiot [ Mon Mar 29, 2010 6:24 pm ]
Post subject:  Not the lift...it's the profile....
Quote:
The cams we have now can out flow what the head is capable of supporting (even after porting).
In this application the roller lobe profile is what you are after, it's especially useful in the "boost" crowd where the steep lobe ramps..litterally allow the valve to go from closed to 100% open in a degree or so...let the turbo pack the cylinder during the wide crown of the lobe, then slap the valve shut to prevent much loss during overlap...

Most current V-8 profiles tend to put about .750 lift after the rocker ratio is applied, that's just too much for us, and even .600 is not workable... in this case I think a roller with about a max lift with stock rockers of .450 for street to .550(tops for drag only I think)...would do the job, nicely...

But then again, the price is...what you spend to get the edge or go where not many have gone before.

-D.Idiot
Author:  Shaker223 [ Mon Mar 29, 2010 6:49 pm ]
Post subject: 
True but there are some pretty fast flat tappet profiles out there too. Check out some of the @.200" duration numbers of some of the custom profiles available at some of the larger cam grinders.
Author:  CNC-Dude [ Mon Mar 29, 2010 7:05 pm ]
Post subject: 
Granted, a roller won't be for everyone, but one advantage a roller will always have over a flat tappet is friction loss. By design, a rolller can always tolerate much steeper ramps than a flat tappet can, and be less harsh on the valvetrain. If a hydraulic roller lifter can be found to work in the slants, you can literally have the best of both worlds, very fast opening ramps like a race cam, and no valve adjustment maintenance.
Author:  CNC-Dude [ Mon Mar 29, 2010 9:37 pm ]
Post subject: 
Quote:
I have made the oil pump drive gears out of C630 bronze alloy and those hold-up well. (aluminum nickel bronze)
I actually have one in my daily driver street car and it is holding-up well. (about 8000 miles on it so far)

Making these gears is pretty easy.
DD

Image
I apologize Doc for not doing a more thorough search on here. But it looks as if you have solved the oil pump gear problem all together. I also have had good success with roller cams on the street in some on my personal vehicles with bronze gears, but some of the earlier comments about them made me think that in the Slants their might be other issues that I wasn't aware of that made them more prone to rapid wear than in other applications.
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