Roller Cam Bearings?
12-22-2015, 09:31 AM
#31
Regarding cam questions it might be worth your time to contact somebody like Cam Motion in Baton Rouge, LA. They are a high end custom performance cam grinding company. (Truth be known I bet many of the custom cams on this site are ground by them). They are very knowledgeable and willing to spend time with you explaining the nuances of these cam aspects. Check out their web site and you get an idea of their pedigree.
Keep in mind that I personally don't know squat about anything but I can get it figured out.
Regarding 9,500 RPM, cam RPM is Engine RPM/2 (4750). My Harley Davidson uses roller rod bearings with dry sump oiling at 7,500 RPM (not a typo) and bearing failure is at the bottom of my concerns. Just saying.
And enough is always just the starting point for improvement.
Keep in mind that I personally don't know squat about anything but I can get it figured out.
Regarding 9,500 RPM, cam RPM is Engine RPM/2 (4750). My Harley Davidson uses roller rod bearings with dry sump oiling at 7,500 RPM (not a typo) and bearing failure is at the bottom of my concerns. Just saying.
And enough is always just the starting point for improvement.
12-22-2015, 09:34 AM
#32
Banned
No, larger bearing means more surface area and more surface speed for the same RPM. I think the differences between cam journal diameters is moot (regarding heat) as compared to the gains in valve train stability, but we're also not turning 10K rpm here. PS and cup guys are also running 9 journal cams, so I don't think heat is the issue. Everything in an engine is a compromise and there is always a give and take to consider.
Last edited by horsepower1; 12-22-2015 at 09:52 AM.
12-22-2015, 09:55 AM
#34
Mike I don't really look at it like building a pro stock style engine. I look at it like modernizing a BBC. When I started all this I had I couple goals. Make as close to 1000hp N/A on pump gas as I could. Secondly get the boat over 100mph. And lastly beat up on the guys that I boat with. We are a pretty close bunch. Talk a lot of crap to each other you get my drift. So we will see what happens. This isn't some thrown together project. Each part of this build has been carefully looked at and at the end of the day I have a lot of confidence that it will turn out great.
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12-22-2015, 05:16 PM
#36
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Mike I don't really look at it like building a pro stock style engine. I look at it like modernizing a BBC. When I started all this I had I couple goals. Make as close to 1000hp N/A on pump gas as I could. Secondly get the boat over 100mph. And lastly beat up on the guys that I boat with. We are a pretty close bunch. Talk a lot of crap to each other you get my drift. So we will see what happens. This isn't some thrown together project. Each part of this build has been carefully looked at and at the end of the day I have a lot of confidence that it will turn out great.
12-22-2015, 06:04 PM
#37
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Mike I don't really look at it like building a pro stock style engine. I look at it like modernizing a BBC. When I started all this I had I couple goals. Make as close to 1000hp N/A on pump gas as I could. Secondly get the boat over 100mph. And lastly beat up on the guys that I boat with. We are a pretty close bunch. Talk a lot of crap to each other you get my drift. So we will see what happens. This isn't some thrown together project. Each part of this build has been carefully looked at and at the end of the day I have a lot of confidence that it will turn out great.
I think a good start to finish build thread on your piece would be in order when completed.
12-23-2015, 10:14 AM
#38
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Plain babbitt cam bearings in my experience are junk above 750 hp with a SOLID ROLLER cam . When a plain babbitt or conventional non roller bearing fails you will see a loss in oil pressure above 5000.00 worsening exponentially. If you don't catch it in seconds you will cause rapid oil starvation and boom
Goes your 35000.00 1000 hp motor. It's insurance and if I were to go racing boats I would endure the maintenance required for abating solid roller cam demons. My boat has a hyd. Roller
I have no problems running 4800 for 70 miles non stop.
solid roller. Roller cam bearings ain't hard or expensive and you can turn the motor by hand and insure proper cam alignment under a load the bearing ain't tin like babbitt. If you intend 7500 + rpm and a 1000 hp don't be afraid if you don't know ask a real engine builder. Sure as **** I blown 6 540s in 4 years . My learning curve.
Goes your 35000.00 1000 hp motor. It's insurance and if I were to go racing boats I would endure the maintenance required for abating solid roller cam demons. My boat has a hyd. Roller
I have no problems running 4800 for 70 miles non stop.
solid roller. Roller cam bearings ain't hard or expensive and you can turn the motor by hand and insure proper cam alignment under a load the bearing ain't tin like babbitt. If you intend 7500 + rpm and a 1000 hp don't be afraid if you don't know ask a real engine builder. Sure as **** I blown 6 540s in 4 years . My learning curve.
12-23-2015, 10:35 AM
#39
Plain babbitt cam bearings in my experience are junk above 750 hp with a SOLID ROLLER cam . When a plain babbitt or conventional non roller bearing fails you will see a loss in oil pressure above 5000.00 worsening exponentially. If you don't catch it in seconds you will cause rapid oil starvation and boom
Goes your 35000.00 1000 hp motor. It's insurance and if I were to go racing boats I would endure the maintenance required for abating solid roller cam demons. My boat has a hyd. Roller
I have no problems running 4800 for 70 miles non stop.
solid roller. Roller cam bearings ain't hard or expensive and you can turn the motor by hand and insure proper cam alignment under a load the bearing ain't tin like babbitt. If you intend 7500 + rpm and a 1000 hp don't be afraid if you don't know ask a real engine builder. Sure as **** I blown 6 540s in 4 years . My learning curve.
Goes your 35000.00 1000 hp motor. It's insurance and if I were to go racing boats I would endure the maintenance required for abating solid roller cam demons. My boat has a hyd. Roller
I have no problems running 4800 for 70 miles non stop.
solid roller. Roller cam bearings ain't hard or expensive and you can turn the motor by hand and insure proper cam alignment under a load the bearing ain't tin like babbitt. If you intend 7500 + rpm and a 1000 hp don't be afraid if you don't know ask a real engine builder. Sure as **** I blown 6 540s in 4 years . My learning curve.
What I was trying to find out from the guys who have ran rollers is who's bearings is everyone using. Are there any to stay away from... That sort of thing.
But putting up a post saying your stuff blew up because it had a Babbitt bearing in it. I'm sorry but there has to be more to the story.
12-23-2015, 06:37 PM
#40
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Plain babbitt cam bearings in my experience are junk above 750 hp with a SOLID ROLLER cam . When a plain babbitt or conventional non roller bearing fails you will see a loss in oil pressure above 5000.00 worsening exponentially. If you don't catch it in seconds you will cause rapid oil starvation and boom
Goes your 35000.00 1000 hp motor. It's insurance and if I were to go racing boats I would endure the maintenance required for abating solid roller cam demons. My boat has a hyd. Roller
I have no problems running 4800 for 70 miles non stop.
solid roller. Roller cam bearings ain't hard or expensive and you can turn the motor by hand and insure proper cam alignment under a load the bearing ain't tin like babbitt. If you intend 7500 + rpm and a 1000 hp don't be afraid if you don't know ask a real engine builder. Sure as **** I blown 6 540s in 4 years . My learning curve.
Goes your 35000.00 1000 hp motor. It's insurance and if I were to go racing boats I would endure the maintenance required for abating solid roller cam demons. My boat has a hyd. Roller
I have no problems running 4800 for 70 miles non stop.
solid roller. Roller cam bearings ain't hard or expensive and you can turn the motor by hand and insure proper cam alignment under a load the bearing ain't tin like babbitt. If you intend 7500 + rpm and a 1000 hp don't be afraid if you don't know ask a real engine builder. Sure as **** I blown 6 540s in 4 years . My learning curve.
