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Roller Cams?

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Discussion Starter · #1 ·
Ok, now I'm trying to buy a camshaftkit but want a roller cam. I want to know what stage camshaft I can get while still staying in the 90-100 octane range. :help:
Also, where can I find a Roller cam?
 

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I havn't heard of a roller cam for an ATV?? but I am probably going with the Rocket Factory stage II cam. From what I have picked up from this forum, It is supposed to give a huge increase in Horse Power along with porting and High compression piston. (and of course the basic 3 mods) :thumbsup:
 

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digitalhearing said:
As I study the photo closer I see that at the bottom it says yamaha 06-07. so I gues it IS the raptor setup?? I remember on cars they were not really a roller cam, but "roller rockers" ? :help:



Yes the photo is of the 06 thru 07 Raptor 700R.

On the High performance Automotive side because of the push rod design we have both roller rockers as well as roller cams. A lot of factory engines now come with roller camshafts.
 

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roller rockers also allow a "steeper angle" lobe to be used, thus you can have more lift without the duration, it also allows your valve to open and close more quickly. but don't forget the stronger valve springs
 

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Discussion Starter · #10 ·
Thanks, I will go with the stage II cam and a high compression piston but what should be the ration 11:1or 12:1??? Also what octane fuel would I have to use for those mods. Right now I have LTE duals, pro flow filter and I custom made my air box lid out of a plate of polished stainless steel, it looks pretty sweet. And of course a PCIII.
 

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Good question on the compression, :3question:GYTR....I want to run Hi octane pump gas and NOT have to buy racing fuel or Alcohol. Is 10.75:1 the right choice?? :unsure: I can't wait to make my decision and start on it.
 

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flybyraptor said:
roller rockers also allow a "steeper angle" lobe to be used, thus you can have more lift without the duration
Not trying to split hairs here ...
I think you mean roller lifters, roller rockers have no effect on lobe slope/angle. And I wouldn't classify a valve train setup with roller rockers as having a "roller camshaft". You can have one with out the other.
 

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RLJ3RD said:
flybyraptor said:
roller rockers also allow a "steeper angle" lobe to be used, thus you can have more lift without the duration
Not trying to split hairs here ...
I think you mean roller lifters, roller rockers have no effect on lobe slope/angle. And I wouldn't classify a valve train setup with roller rockers as having a "roller camshaft". You can have one with out the other.
In a engine where there are lifters yes that is true but if you look at the raptor schematic above, there aren't lifters. the roller rocker connects directly to the cam, if I was talking about a 5.0 in a mustang-or any other OHV engine you would be right.
 

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flybyraptor said:
RLJ3RD said:
flybyraptor said:
roller rockers also allow a "steeper angle" lobe to be used, thus you can have more lift without the duration
Not trying to split hairs here ...
I think you mean roller lifters, roller rockers have no effect on lobe slope/angle. And I wouldn't classify a valve train setup with roller rockers as having a "roller camshaft". You can have one with out the other.
In a engine where there are lifters yes that is true but if you look at the raptor schematic above, there aren't lifters. the roller rocker connects directly to the cam, if I was talking about a 5.0 in a mustang-or any other OHV engine you would be right.
Yes I won't argue that point with you as to which side the roller is on. I guess my point is that rollers don't nessitate a roller camshsft. It's been common practice (and eluded to here in the thread) that production vehicles now come with roller setups. My contention is that the roller lifters(followers) (in this case) are for increased engine efficiency and not merely performance. Hence just cause you have roller lifeters doesn't mean you have a roller camshaft. :)
 

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RLJ3RD said:
flybyraptor said:
roller rockers also allow a "steeper angle" lobe to be used, thus you can have more lift without the duration
Not trying to split hairs here ...
I think you mean roller lifters, roller rockers have no effect on lobe slope/angle. And I wouldn't classify a valve train setup with roller rockers as having a "roller camshaft". You can have one with out the other.

Exactly, all roller rockers do is reduce friction, are stronger and give more clearance for larger diameter valve springs as well as give you options on rocker ratios to alter the lift at the valve in an automotive application. On the 700R the cam follower is part of the camshaft side of the rocker arm but still has nothing to do with the cam profile.

The things flyby raptor mentoned are all about the cam profile. The advantage of a roller cam is you can run a much more aggresive profile and still maintain contact between the lobe and cam follower and run a lot higher spring pressure on the seat and over the nose. Also a roller cam will survive in a fuel diluted enviroment much better than a flat tappet camshaft.
There's nothing like a good roller ground on a small base circle with split lift and duration as well as tight lobe centers, for explosive acceleration, that and the unmistakable machine gun lope 8) In automotive applications you can run a lot more cam with a roller and still maintain streetability, I think the same rule of thumb will apply to the roller cam on the 700R's and low speed ridiability :thumbsup:
 

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Discussion Starter · #17 ·
RaptorRandy27 said:
RLJ3RD said:
flybyraptor said:
roller rockers also allow a "steeper angle" lobe to be used, thus you can have more lift without the duration
Not trying to split hairs here ...
I think you mean roller lifters, roller rockers have no effect on lobe slope/angle. And I wouldn't classify a valve train setup with roller rockers as having a "roller camshaft". You can have one with out the other.

Exactly, all roller rockers do is reduce friction, are stronger and give more clearance for larger diameter valve springs as well as give you options on rocker ratios to alter the lift at the valve in an automotive application. On the 700R the cam follower is part of the camshaft side of the rocker arm but still has nothing to do with the cam profile.

The things flyby raptor mentoned are all about the cam profile. The advantage of a roller cam is you can run a much more aggresive profile and still maintain contact between the lobe and cam follower and run a lot higher spring pressure on the seat and over the nose. Also a roller cam will survive in a fuel diluted enviroment much better than a flat tappet camshaft.
There's nothing like a good roller ground on a small base circle with split lift and duration as well as tight lobe centers, for explosive acceleration, that and the unmistakable machine gun lope 8) In automotive applications you can run a lot more cam with a roller and still maintain streetability, I think the same rule of thumb will apply to the roller cam on the 700R's and low speed ridiability :thumbsup:







Yes, that is why I wanted a Roller cam, I have a 1964 Vette and I pulled the engine apart because it blew up. Come to find out, the camshaft was worn badly, in those they only last about 5 thousand miles. This is why I want a roller cam, they last longer and have less friction, ultimatley giving you more performance. ;)
 
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