Cast cam and 13mm pump?

Many times broken cast cams are due to smaller O.D. cam cores or inferior chinese castings....not all cast cams are created equal. The out side diameter of the cam handles most of the torsional loads. If you have a smaller core diameter or have inconsistent metallurgy and flawed hardening and inclusions, it is much more likely to happen. To help keep our cams alive, we increased the O.D. of our cast cams on the first two cylinders and had the first cylinder machined smooth with a radius at every lobe and journal transition, which is where they typically break.

Steel cams typically break less, but a few years ago another manufacturer for no apparent reason decreased their steel cam core diameter to 1.1" and started seeing failures on some VERY expensive engines. After the cam diameter was increased, the failures stopped. Although steel cams usually break less, be sure to ask about the diameter of the cam core. With radical 13mm pumps being traded in for 14-17mm pumps, you need to make sure your cam diameter is at least 1.2" If not, save your money ;)

Also a lot of people have had good luck with steel cams and no bushings. I have seen them run without bushings many times with no failures. If it was my block though, I would run bushings.
Outside diameter and the change in velocity are the two main factors, the more rpm and load that change in a shorter amount of time, the greater the chance for a fracture.
 
I had good luck with a cast cam and 13mm pump. 188/220 made 1218hp on old ugly, and ran about 25k miles before I broke a ring. Now an F1 billet cam lasted about 1500 miles before it had to be changed. Don made good 24V injectors but his cams were junk.
 
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Texashighways said:
Steel cams typically break less, but a few years ago another manufacturer for no apparent reason decreased their steel cam core diameter to 1.1" and started seeing failures on some VERY expensive engines. After the cam diameter was increased, the failures stopped. Although steel cams usually break less, be sure to ask about the diameter of the cam core. With radical 13mm pumps being traded in for 14-17mm pumps, you need to make sure your cam diameter is at least 1.2" If not, save your money ;)
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I will disagree with you this one. I have seen those cams, and the reason for breaking them was not just the beam size. It was the manufacturing process and material. Surface finish and corner radius on the cam had a lot to do with it, as well as the material, and typical heat treating technique they have been using. We have had zero issue going below that on our Tool Steel cam cores.

But totally agree with you on the cam bushings. I have seen the steel cams work on non bushed blocks, but if I had the engine block out, there would be no doubt that it would be getting bushed. Its called preventive maintenance.
 
cams

So for sled pulling applications a billet cam would be the best way to go? a I was going to have my block line bored for all cam bushings. do you think id be better off with cam bearings at the 1100-1200 hp mark?
 
Ran a Scheid ugl blank cast cam 234/254-105 with a northeast 13mm for two years until an input shaft let loose and the spike in the motor snapped the cam. Brad says with the new front covers having bearings in it to support the nose that the breakage is pretty much eliminated. Pulled that pump and threw it on a 12v motor with a Scheid drop in street cam and finished the year out. Now I have a Hamilton steel cam and bushings so no issues either. I heard it's like 30+ hp to run a built 13mm pump which is why the rapid change puts a ton of pressure on the snout of the cam.
 
ILLINOISRAM said:
Ran a Scheid ugl blank cast cam 234/254-105 with a northeast 13mm for two years until an input shaft let loose and the spike in the motor snapped the cam. Brad says with the new front covers having bearings in it to support the nose that the breakage is pretty much eliminated. Pulled that pump and threw it on a 12v motor with a Scheid drop in street cam and finished the year out. Now I have a Hamilton steel cam and bushings so no issues either. I heard it's like 30+ hp to run a built 13mm pump which is why the rapid change puts a ton of pressure on the snout of the cam.
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Mine did the exact same thing
 
That talk of the bearing in the front cover is bullchit. I broke one in 2 runs with that bearing. It was a scheid cam with a scheid 13mm Auto pump at the time. Been running a billet cam ever since.
 
2000wvdodge said:
That talk of the bearing in the front cover is bullchit. I broke one in 2 runs with that bearing. It was a scheid cam with a scheid 13mm Auto pump at the time. Been running a billet cam ever since.
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Do you have a picture of the bearing in the cover?
 
The more I read this I get a little nervous, I posted here earlier about no problems still don't. I'm running a Hamilton 188/220 with a 13mm pump and turn 4400 when I run it. Is it a time bomb or if its made it this long role with it?
 
56cummins said:
Do you have a picture of the bearing in the cover?
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I don't, it is scheids front cover with the bearing they sent along with the cam retainer. It was a small caged needle bearing that pressed in the front cover.
 
Since we're on the topic of cast cams and hot 13mm injection pumps... I think we're playing with fire running running this cast Hamilton cam up to 5500 RPM with a hot Northeast 13mm injection pump. When this engine was in "Frankenstein", we broke an input shaft out on the highway and the engine spiked to 6200 RPM on the data logger, but the cam is still trucking along.

FYI, this video was shot a week or so ago before the "Big" injectors went in, HP is much higher now!!!

[ame="http://www.youtube.com/watch?v=7Zrx362yze8"]http://www.youtube.com/watch?v=7Zrx362yze8[/ame]
 
I am shifting into OD at 4,700 with my 188/220, 80/96/1.10 t4, and 13mm b&p 913 cam pump. I am very satisfied with mine. I am also running the scheid cover with the needle bearing on the cam snout.
 
Levi_plummer said:
I am shifting into OD at 4,700 with my 188/220, 80/96/1.10 t4, and 13mm b&p 913 cam pump. I am very satisfied with mine. I am also running the scheid cover with the needle bearing on the cam snout.
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Does that single s480/96 stay lite up good at the track? I ran a single 75/96/1.0 t4 on a cr and it barked like crazy on every shift.
 
Levi_plummer said:
I am shifting into OD at 4,700 with my 188/220, 80/96/1.10 t4, and 13mm b&p 913 cam pump. I am very satisfied with mine. I am also running the scheid cover with the needle bearing on the cam snout.
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How does it compare to your old 92mm turbine?
 
I am afraid I am having problems staying on top. But it does seem to run better than my old 92 turbine. I think it needs a smaller compressor to stay on top in that small t4 housing. Or I need to get a new charger in a 1.32 housing.
 
I'm running a cast hamilton with a 13mm, spinning 4500-5000 depending on the track, planning on swapping to a steel cam this winter when its apart however. A buddy of mine broke his cast at the starting line a couple weeks ago.
 
Inbred Inline said:
I'm running a cast hamilton with a 13mm, spinning 4500-5000 depending on the track, planning on swapping to a steel cam this winter when its apart however. A buddy of mine broke his cast at the starting line a couple weeks ago.
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What brand cast cam was it, anyone had a Hamilton break?
 
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