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daboatman1 12-14-2004 09:19 PM

Roller Cam selection
 
Question: When comparing camshaft specs @ .050 is a roller cam the same as a flat tappet? Example, if both roller & flat tappet cams have the same 230/236 @ .050 duration and the same lift is one bigger than the other? Is the idle quality the same? And do the benefits out way the extra $$$ spent? The roller profile of valves opening & closing is a bit scary. I guess it's like comparing apples and oranges. With all the great input on head & cam combos I was thinking of bumping up my game.

Input appreciated, signed confused

X-Rated30 12-14-2004 10:12 PM

Re: Roller Cam selection
 
This should be interesting. And yes, I would say the benefit far outweighs the $$$.

Sean H 12-14-2004 10:21 PM

Re: Roller Cam selection
 
once you go roller, you never go back.... :cool:

cooltoys61 12-14-2004 10:29 PM

Re: Roller Cam selection
 
Roller is less of a compromise between HP and torque. The ultimate cam would have a square lobe,,but nobodys figured that one out yet. Less duration with the same area under the curve lets a big lift roller idle and make torque while still giving good HP at the other end.

wannabe 12-15-2004 09:41 AM

Re: Roller Cam selection
 

Originally Posted by cooltoys61
Roller is less of a compromise between HP and torque. The ultimate cam would have a square lobe,,but nobodys figured that one out yet. Less duration with the same area under the curve lets a big lift roller idle and make torque while still giving good HP at the other end.


The ultimate cam would be NO CAM-- electronic solenoid opened valves, again no one has done that.

Wannabe

cstraub69@comcast 12-15-2004 09:44 AM

Re: Roller Cam selection
 
For a flat to equal a roller, a general rule is the flat needs to be about 20 degrees larger in duration.

Rollers by far in low rpm applications such as cars and boat will make more power due to the aggressive ramp and flank rates to actuate the valve.

With the government banning the use of some additives in oil that promoted wear resistance for flat lifters, you are much better off in the long run to run roller cams and lifters.

I would contact RMbuilder and have Bob go over some options on power up grades.

Chris

ratman 12-15-2004 10:48 PM

Re: Roller Cam selection
 
Wannabe, the f1 car teams are working that one out right now. you will see 20k+ rpm f1 engines in the next year or two. ratman

hpy540 12-16-2004 07:47 AM

Re: Roller Cam selection
 

Originally Posted by wannabe
The ultimate cam would be NO CAM-- electronic solenoid opened valves, again no one has done that.

Wannabe

BMW has done it on their 7 series

dyno 12-16-2004 07:59 AM

Re: Roller Cam selection
 
For me the ? is always whats in it for me.....dyno horse power! it costs better than 1K to switch to a roller set -up and get what???20-30hp that translates into maybe 1-2 mph at wot....not worth it for me ....yet....

TomR 12-16-2004 09:01 AM

Re: Roller Cam selection
 
Hi Billy,
Pretty interesting reading. Wonder if we can adapt this technology to a BBC?


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