Max RPM on non billet cam???

zstroken said:
I am saying what broke the bolt more than anything is the loads on the bevel gear of the cam, pushing the gear out and walking it off the cam. There was enough force that it popped the bolt.
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Like Zstroken said, In most cases the cam gear is pushed off due to the force that it takes to turn bigger pumps ie. 13mm and up. The Helix teeth on the pump gear when meshed with the cam gear push outward when under a heavy load. Also a mis alinged keyway can do the same thing. I work at Mack trucks powertrain divistion in the transmission dept. making trans gears. The Helix gears are very quiet compared to straight cut teeth but are not as strong. Im suprised no one has made straight cuts gears for high HP aplications. The timing gears in the Macks were all straight cut. Sorry if I got off topic
 
You are correct Timebomb and Kent did warn me that it may happen, the billet cover with the bearing in it stopped the gear from moving any father outward do to the 1/2 spacer on the end of the cam that bolt goes through and it rides in the front cover bearing and instead pushed the cam back. if it had been a stock front cover i belive it would have gotten into the cover and messed alot of things up
 
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Timebomb said:
Like Zstroken said, In most cases the cam gear is pushed off due to the force that it takes to turn bigger pumps ie. 13mm and up. The Helix teeth on the pump gear when meshed with the cam gear push outward when under a heavy load. Also a mis alinged keyway can do the same thing. I work at Mack trucks powertrain divistion in the transmission dept. making trans gears. The Helix gears are very quiet compared to straight cut teeth but are not as strong. Im suprised no one has made straight cuts gears for high HP aplications. The timing gears in the Macks were all straight cut. Sorry if I got off topic
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I don't know how the helical gears wouldn't be as strong? If anything they would tend to be stronger because there is more surface area per tooth. The only drawback I can see is the need for thrust bearings. I copied this from an encyclopedia. "Spur gears make a characteristic whine at high speeds and can not take as much torque as helical gears because their teeth are receiving impact blows. Whereas spur gears are used for low speed applications and those situations where noise control is not a problem, the use of helical gears is indicated when the application involves high speeds, large power transmission, or where noise abatement is important." It takes more power to drive a P-Pump than it does a CP3. That's why the 3rd gens use spur gears.
 
The gears on our truck actually aren't helical gears. I believe a helical gear is a curved tooth. We have like a bevel gear or something. I will agree on the strength, the nice thing about straight cut gears is not nearly the same amount of thrust load.
 
zstroken said:
The gears on our truck actually aren't helical gears. I believe a helical gear is a curved tooth. We have like a bevel gear or something. I will agree on the strength, the nice thing about straight cut gears is not nearly the same amount of thrust load.
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According to everything I've seen they're helical. Here's a link.
 
Mine has the Helix 3 cam in it, but at the moment I am just running a 12mm pump, but am putting a 13mm pump and hoping to turn 5000 plus. So are yall saying the H3 will handle it??? Also the busings are only to clear the larger cam profiles..they have nothing to do with the billet material?

Thanks

Scott
 
sigmon03 said:
Just curious on the opinions out there. I am trying to stay away from the billet cam just to avoid the boring of the cam journals, regrinding of billet tappets etc. What kind of RPM can aftermarket cams run like the H2/H3's etc. Looking for 4500+ on the track, and am planning on balancing the bottom end etc.

Thanks

Scott
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EEP cam, no machining required.
 
Peak Diesels' cams have a bolt on gear too and they are a whole hell of allot cheaper.

Jim
 
jfaulkner said:
I don't know how the helical gears wouldn't be as strong? If anything they would tend to be stronger because there is more surface area per tooth. The only drawback I can see is the need for thrust bearings. I copied this from an encyclopedia. "Spur gears make a characteristic whine at high speeds and can not take as much torque as helical gears because their teeth are receiving impact blows. Whereas spur gears are used for low speed applications and those situations where noise control is not a problem, the use of helical gears is indicated when the application involves high speeds, large power transmission, or where noise abatement is important." It takes more power to drive a P-Pump than it does a CP3. That's why the 3rd gens use spur gears.
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Yes Iam very sorry I mislead the thread, It must have been one to many micro brews in me. Helical cut gears are much stronger due to having about 30% more contact area with the meshing teeth. Spur gears are much cheaper to produce and do not require the more precise syncronizers in a transmission aplication. In my opinion spur gears would work great for a large P-Pumped truck because it wouldnt put the thrust load on the cam.

Can you get specs on that cam? I'm going to have one (for sale) early next year. Jim
I also would like to get some specs on these cams. Is there anyone who has stock specs as well. Lift,Duration,Timing events, for each ???
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Jim Fulmer said:
Can you get specs on that cam? I'm going to have one (for sale) early next year.

Jim
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yeah right. go ahead and ask doug for that see what he says.
 
joeservo said:
yeah right. go ahead and ask doug for that see what he says.
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From what I know about him he would even tell you a torque spec they use.....got to love the "I've got a secret people"

I'll get someone with the right equipment to figure it out then I'll post it on the net.

Jim
 
Dont know what is so secret about them. Anyone with a degree wheel and a dial indicator can figure em out. Add a piece of graph paper to your tools and you can see how aggressive the profile is. I have the spec for the cam I was going to run some where around here as soon as I find it Ill post them.

Adam
 
BigYellowIron said:
Dont know what is so secret about them. Anyone with a degree wheel and a dial indicator can figure em out. Add a piece of graph paper to your tools and you can see how aggressive the profile is. I have the spec for the cam I was going to run some where around here as soon as I find it Ill post them.

Adam
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That's kinda what I was thinking.:doh: Anyone that has ever degreed a cam in could get those specs in a heart beat
 
But for someone whos in the market to buy cam, it would be foolish to buy it, install it and then get your info after you degree it. The whole time not knowing what its gonna be. Now Im ready for the person to reply "So what if you had the info from cam to cam, are you educated enough on forced induction mainly diesel engines to use it"
 
Here is the specs I was going to run:

Lobe seperation:
107*
Duration
intake- 224
Exhaust- 228
Lift
Intake- 335
Exhaust- 340

Dunno How well it will work with my combo, but gonna try it anyway.
 
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