Home » Public Forums » GMCnet » Roller Camshaft
| Roller Camshaft [message #272492] |
Mon, 23 February 2015 06:51  |
 |
Loffen
Messages: 1087
Registered: August 2013
Location: Norway
Karma: 1
|
Senior Member |
|
|
ny recommendations ? I have been thinking of the Crane 809611 does anyone have any experience with it ?
1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green,
And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel
in Norway
|
|
|
|
| Re: Roller Camshaft [message #272493 is a reply to message #272492] |
Mon, 23 February 2015 09:03  |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
|
Senior Member |
|
|
Jim Bounds and his engine builder are the gurus of roller cams. Ask him.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
|
|
|
|
|
|
| Re: Roller Camshaft [message #272501 is a reply to message #272492] |
Mon, 23 February 2015 12:44 |
bwevers
Messages: 597
Registered: October 2010
Location: San Jose
Karma: 5
|
Senior Member |
|
|
Loffen,
From what I understand, the best RV cams have no more than 204/214 (intake/exhaust) duration at 0.050" lift and 110º or 112º lobe centers for good low RPM torque.
The Crane you mentioned has 214/222 duration at 0.050" lift and would have a hot rod, rough idle, for more power at high rpm, if that's what you want.
And you will probably need high performance rocker arms and springs to go with the high lift profile .520/.542 lift.
And also 3.70s or 4.10 gears.
This Crane cam would probably have less power from idle to 2500RPM, than the stock cam.
I believe these are the specs for the stock 455 camshaft :
Part # -OVRLP--Dur----lift------
400117 44 258/272 .435/.435 455 Irrig, Mar, hi-comp ex Pol.,Toro, hi-perf.
For my personal choice I decided to save some $$ and go with a flat-tappet 1984 Hurst Olds camshaft with 194/207 duration (CS651).
It has excellent off-idle torque up to 3000 RPM. It has slightly more lift and duration than the stock camshaft.
Sealed Power CS651 Cam
----CS651 61 275/289 .437/.437 ILC=108 ELC=110
@ 0.050"-----194/207
Here's some information from Lunati:
-------------------Theoretical--@0.50"----
-------------------- Int/Exh----Int/Exh----Lift----------LCA
LUN-10420211 262/262 207/207 .461/.461 112/106 Idle to 5000
LUN 10420285 260/260 210/210 .470/.470 110 smooth idle
LUN 10420700 250/256 207/213 .466/.485 112 towing applications. Good idle.
LUN 10420701 256/262 213/219 .485/.499 112 Fair idle, good torque low to mid range
Regards,
Bill
Bill Wevers GMC49ers, GMC Western States
1975 Glenbrook - Manny Powerdrive, OneTon
455 F Block, G heads
San Jose
|
|
|
|
| Re: Roller Camshaft [message #272504 is a reply to message #272501] |
Mon, 23 February 2015 13:14 |
appie
Messages: 902
Registered: April 2013
Location: denmark
Karma: 2
|
Senior Member |
|
|
Talked to Dick Paterson about rolercam. He thinks they are a wast of money under motorhome conditiond
Appie
eleganza 76 "Olga" now sadly sold
6 wheel discbrake
Quadrabags
Springfield stage 2 462 olds
Manny tranny
( pictures at http://www.gmcmhphotos.com/photos/g6489-olga.html
Fulltiming in Europe july 2014 til july 2016
Denmark
|
|
|
|
| Re: Roller Camshaft [message #272512 is a reply to message #272504] |
Mon, 23 February 2015 18:37 |
|
Loffen
Messages: 1087
Registered: August 2013
Location: Norway
Karma: 1
|
Senior Member |
|
|
Yes it is a bit in the upper range, the reason for going with the Crane roller is that you can run with a std distributor gear and there might be possible to advance it 4 degrees to lower the power band.
I will also have a 3.42 final drive and that will help a little together with rising the compression a point or so.
I know some will say that a roller is a waste of money on a RV, I do not agree, less friction and wear, better lobe profiles together with the oil quality are some of the reasons, I sent an email to Crane so let's see what they say.
I am also pretty sure someone here are using that camshaft and was hoping he would come through and share his experience.
This is what Crane says about the cam, and I do not think the specs are to bad for a large displacement engine, yes it would have a fair idle on a 350 but not on a 455
Excellent low end torque, good idle, daily usage, towing,
performance and fuel efficiency, 2600-3000 cruise RPM,
8.75 to 10.5 compression ratio advised
1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green,
And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel
in Norway
[Updated on: Mon, 23 February 2015 19:04] Report message to a moderator |
|
|
|
| Re: Roller Camshaft [message #272515 is a reply to message #272512] |
Mon, 23 February 2015 19:16 |
Neil
Messages: 271
Registered: July 2007
Location: Los Angeles and Magalia, ...
Karma: 1
|
Senior Member |
|
|
If you go to Crane's webpage, you'll see their mildest roller cam, which I got for my rebuild. Works just fine. Better than stock? Who knows?
Neil
76 Eleganza now sold
Los Angeles
|
|
|
|
|
|
|
|
|
|
|
|
| Re: Roller Camshaft [message #272559 is a reply to message #272549] |
Tue, 24 February 2015 12:07 |
Carl S.
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
|
Senior Member |
|
|
Everyone I know that is running the Comp Cams "Kryptonite" cam, developed for the GMC Motorhome by Jim Bounds, Richard Archer, Steve Ferguson, and others, is VERY happy with it's performance either as a roller or flat tappet cam. My engine is completely stock, except for a Cloyes Timing chain and a Rockwell intake, but I plan to run the Comp cam when it becomes necessary to rebuild.
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
|
|
|
|
| Re: [GMCnet] Roller Camshaft [message #272560 is a reply to message #272555] |
Tue, 24 February 2015 12:43 |
Keith V
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
|
Senior Member |
|
|
James Hupy wrote on Tue, 24 February 2015 11:23The principal advantage in roller cams today is longevity. Lift is lift,
duration is duration, rollers allow steeper opening ramp angles. The fly in
the soup today is the lack of wear additives in modern oils. Flat tappet
cams are right on the edge of durability without zinc and phosphorous in
the oil. Especially during break in. Read any cam mfg. stuff. They know.
Jim Hupy
Salem, Oregon
78 GMC ROYALE 403
On Feb 24, 2015 9:06 AM, "Keith V" wrote:
> I have the flat tappet lifter JIm B recommends.
> I've always wondered if the roller was any better at low lifts, low RPM.
> I must say that the cam I have sure sounds pretty at idle 
> Not a lope, but a good strong heartbeat
> --
> Keith Vasilakes
> Mounds View. MN
> 75 ex Royale GMC
> 69 Vette
> 29 Dodge
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
I dunno, a flat tappet cam will last pretty long if broken in right and used with good oil.
I plan on upping the zinc for the foreseeable future
Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
|
|
|
|
| Re: [GMCnet] Roller Camshaft [message #272561 is a reply to message #272555] |
Tue, 24 February 2015 13:25 |
GMC.LES
Messages: 505
Registered: April 2014
Karma: -2
|
Senior Member |
|
|
Roller lifters are not necessarily longer lived. Google roller lifter failures and you should find lots of reading material. I am going through such situation right now with my 6.4 powerstroke. They are notorious for having rollers flat spot and wipe out cam lobes. If not caught immediately, it has the potential for scrapping the block as well due to the lifter body swelling and jamming in the bore.
Not to knock what Koba and JimB have developed, but I would be concerned about the longevity of custom aftermarket parts that have very little development time in comparison to what a production line engine has undergone. I think I'd prefer banking my money on a flat tappet cam in my 455.
Les Burt
Montreal
'75 Eleganza 26'
The EWIP (Eternal Work In Progress)
> On Feb 24, 2015, at 12:23 PM, James Hupy wrote:
>
> The principal advantage in roller cams today is longevity. Lift is lift,
> duration is duration, rollers allow steeper opening ramp angles. The fly in
> the soup today is the lack of wear additives in modern oils. Flat tappet
> cams are right on the edge of durability without zinc and phosphorous in
> the oil. Especially during break in. Read any cam mfg. stuff. They know.
> Jim Hupy
> Salem, Oregon
> 78 GMC ROYALE 403
>> On Feb 24, 2015 9:06 AM, "Keith V" wrote:
>>
>> I have the flat tappet lifter JIm B recommends.
>> I've always wondered if the roller was any better at low lifts, low RPM.
>> I must say that the cam I have sure sounds pretty at idle :)
>> Not a lope, but a good strong heartbeat
>> --
>> Keith Vasilakes
>> Mounds View. MN
>> 75 ex Royale GMC
>> 69 Vette
>> 29 Dodge
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|
|
|
|
|
|
| Re: [GMCnet] Roller Camshaft [message #272577 is a reply to message #272566] |
Tue, 24 February 2015 18:33 |
 |
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
|
Senior Member |
|
|
Espen,
Heads up - you're going to have to machine the lifters to clear the bottom of the OEM intake manifold on a 455.
http://www.gmccoop.com/koba_built_motors.htm
Scroll down until you come to Oil Supply and there you will find a photo showing how the lifters have been "scalloped."
Regards,
Rob M.
The Pedantic Mechanic
-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Espen Heitmann
Sent: Tuesday, February 24, 2015 2:52 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Roller Camshaft
On the other hand I so is there engines that have been in daily use for 30 years or more with roller lifters with out any problems,
and one of my buddies has used the same roller rockers for 20 years with out failure, what I am trying to say is that it goes both
ways and engine development has moved forward since the 70s so I am not to worried about using a roller camshaft
--
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
|
|
|
|
| Re: [GMCnet] Roller Camshaft [message #272579 is a reply to message #272566] |
Tue, 24 February 2015 19:12 |
GMC.LES
Messages: 505
Registered: April 2014
Karma: -2
|
Senior Member |
|
|
Espen, I totally agree with what you have said. The same logic also applies to how flat tappet engines are surviving with today's oils. You will always find enough documented failures of both lifter designs to justify an argument as to which is superior. Truth is, both are very reliable, and both can fail for various reasons. What I see as the real difference between the systems as applied to Motorhome use is the initial cost of the parts and machining. Roller lifter set-ups can cost over double that of a comparable flat tappet set-up, and both will give you 8-10 mpg.
Les Burt
Montreal
'75 Eleganza 26'
The EWIP (Eternal Work In Progress)
> On Feb 24, 2015, at 3:51 PM, Espen Heitmann wrote:
>
> On the other hand I so is there engines that have been in daily use for 30 years or more with roller lifters with out any problems, and one of my
> buddies has used the same roller rockers for 20 years with out failure, what I am trying to say is that it goes both ways and engine development has
> moved forward since the 70s so I am not to worried about using a roller camshaft
> --
> 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Mean Green Machine,
> And just sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel
> in Norway
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|
|
| Re: [GMCnet] Roller Camshaft [message #272597 is a reply to message #272577] |
Wed, 25 February 2015 05:56 |
|
Loffen
Messages: 1087
Registered: August 2013
Location: Norway
Karma: 1
|
Senior Member |
|
|
Rob, yes on some lifters you will need to grind them a little bit to make them fit, but I have seen others that do look like they will clear the intake.
I am thinking of going with the Alu intake and it would be nice to know if they did rise the runners or if there is enough material to grind scalops in it
USAussie wrote on Wed, 25 February 2015 01:33Espen,
Heads up - you're going to have to machine the lifters to clear the bottom of the OEM intake manifold on a 455.
http://www.gmccoop.com/koba_built_motors.htm
Scroll down until you come to Oil Supply and there you will find a photo showing how the lifters have been "scalloped."
Regards,
Rob M.
The Pedantic Mechanic
-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Espen Heitmann
Sent: Tuesday, February 24, 2015 2:52 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Roller Camshaft
On the other hand I so is there engines that have been in daily use for 30 years or more with roller lifters with out any problems,
and one of my buddies has used the same roller rockers for 20 years with out failure, what I am trying to say is that it goes both
ways and engine development has moved forward since the 70s so I am not to worried about using a roller camshaft
--
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green,
And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel
in Norway
|
|
|
|
| Re: [GMCnet] Roller Camshaft [message #272601 is a reply to message #272579] |
Wed, 25 February 2015 06:07 |
|
Loffen
Messages: 1087
Registered: August 2013
Location: Norway
Karma: 1
|
Senior Member |
|
|
I agree with you Les and it is hard to justify the cost for a roller setup,for me it is more to go all the way, I will use Alu heads and intake anyways to save weight and rise the compression since the cost is minimal over low compression pistons and it will not be any problems to do so with our regular fuel.
Then in my mind the engine is more or less ready for a roller camshaft, so why not take use of the benefits that it has over a regular cam ? yes there is the price issue but othere than that I can not see any bad sides of a roller.
Les Burt[1 wrote on Wed, 25 February 2015 02:12]Espen, I totally agree with what you have said. The same logic also applies to how flat tappet engines are surviving with today's oils. You will always find enough documented failures of both lifter designs to justify an argument as to which is superior. Truth is, both are very reliable, and both can fail for various reasons. What I see as the real difference between the systems as applied to Motorhome use is the initial cost of the parts and machining. Roller lifter set-ups can cost over double that of a comparable flat tappet set-up, and both will give you 8-10 mpg.
Les Burt
Montreal
'75 Eleganza 26'
The EWIP (Eternal Work In Progress)
> On Feb 24, 2015, at 3:51 PM, Espen Heitmann wrote:
>
> On the other hand I so is there engines that have been in daily use for 30 years or more with roller lifters with out any problems, and one of my
> buddies has used the same roller rockers for 20 years with out failure, what I am trying to say is that it goes both ways and engine development has
> moved forward since the 70s so I am not to worried about using a roller camshaft
> --
> 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Mean Green Machine,
> And just sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel
> in Norway
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green,
And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel
in Norway
|
|
|
|
Goto Forum:
Current Time: Mon Nov 18 16:11:45 CST 2024
Total time taken to generate the page: 0.02240 seconds
|
GMCforum
Search
Help
Register
Login
Home
