whats a RV Cam? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

RED72blazer · 11-15-2002, 07:27 AM

It's kinda a stupid question. but is a RV cam really out of an RV?
Can anyone explain this? thanks
matt

Blazer1970 · 11-15-2002, 08:51 AM

An RV cam is a mild performance cam that is designed more to make lower RPM torque than high RPM horsepower. This is the type of cam that would be used in an RV if you wanted to upgrade the motor.

BLACK AND BLUE 67-72 · 11-15-2002, 08:53 AM

No, it's just designed for RV'S and heavy duty towing so they call it an RV cam.

RON WOODGEARD · 11-15-2002, 12:37 PM

BLAZER 1970 is right! An RV cam is a cam designed to be useful in the lower RPM range.. My pulling cam (RV CAM) is actually a pretty good street performance cam. and along with an AUTO, RV TORQUE CONVERTOR,LOW range manifold & carb set up,GEARS, ETC.ETC. My 350 was a very strong pulling engine. I pulled a 4 horse bumper pull horse trailer.

MY CAM SPECS,

DURATION, 272/282
LIFT, 442/465
112 center line
Useful RPM: 1500-5000
TORQUE: 0-3500

RON

ckhd · 11-16-2002, 01:18 PM

There aren't truly RV cams. It's a generalization of a type of cam profile. If the cam is designed to pull, have low end torque, etc... then people will generalize it as a "RV" cam. The cam I have in the '68 has been generalized as a "RV" cam, but when I bought it, it bought it for it's rpm range and torque aspects.

It's the same as a "3/4 race" cam. Really no such thing, but if it has tall lobes, and makes lots of horsepower at high rpm, but can still be driven on the street (with the idle cranked up to 1200rpm or something), then they call it a "3/4 race".

If you want a smart parts guy to take advantage of you, ask him for a "RV" or "3/4 race" cam. If you want what you need, call a cam manufacturer and give them the specifics of your engine (ci, compression, head flow, valve size, rocker ratio, intake/exhaust manifold type, carb info), vehicle, etc.. and tell them what you will be doing with the vehicle, and they will help you pick the right profile for your application. I'd say that Crane probably has at least 6 grinds that could be generalized as "RV" cams, and probably twice as many that could be called "3/4 race" cams.

If you have Desktop Dyno, you can plug in all of your engine specifics, including all the details of your cam, and see if the cam will do what you want.

The cam is the heart of your engine. Pick the wrong one and you'll hate your engine. Pick the right one, and you'll love it.

RON WOODGEARD · 11-16-2002, 05:00 PM

NO SUCH THING AS A 3/4 RACE!!!!!!

Not any more, but to us old farts???!!! this was the way in which we bought a CAMSHAFT.
Before the extended technology there were VERY FEW cams to choose from IE: The race anology, 1/4,1/2,3/4,5/8,and fullrace. And I absolutely agree that a poor cam will really ruin your day, But I guess I still have more trust in a good cam company. You tell them you want an RV cam, and they will take it from there to ask the questions of it's intended usage at what RPM.Weight of vehicle,rear end gearing,Standard or auto, ETC,ETC,
You can do most of the research yourself by getting the camshaft spec sheets. they will tell you what rpm the cam is intended for, as far as H.P and TORQUE. I don't know of a major name cam. company that doesn't offer that information to you. If you are going to really pull with it then you don't care about HP you want brute torque, at the lowest possible RPM. But don't plan on any CAMSHAFT working in the low rpm range and not having everything else "MATCHED" (in other words don't use a cam. that's intended for 0-3500 rpm and install a manifold, carb. combo. that works from 2500-6500 rpm.

No 3/4 RACE CAMS anymore,???,,, Damned I am getting old.

RON

Blue_71 · 11-16-2002, 05:13 PM

i was playing around with cams on desktop dyno, and if you play enough you can find excactly what you need.. so far the highest ive got my motor to was 420 torque@2000 RPM, and i have to pull almost 9 tons with this thing (27500 lbs).. just pick a cam for what you need, speed or brute force

lukecp · 11-16-2002, 09:03 PM

I always thought of a RV cam as one with 204/214 degrees of duration @.050 lift, and around .420-.440 lift. BTW, i have one in my truck and i am very happy with it. However....the power drops off considerably above 4500 RPM, but it runs really strong everywhere else.

11-15-2002, 07:27 AM	#1
RED72blazer urban fourwheelin Join Date: Aug 2002 Location: Seattle Posts: 1,007	whats a RV Cam? It's kinda a stupid question. but is a RV cam really out of an RV? Can anyone explain this? thanks matt

11-15-2002, 08:51 AM	#2
Blazer1970 Registered User Join Date: Dec 1999 Location: Old Mission, MI, USA Posts: 2,510	An RV cam is a mild performance cam that is designed more to make lower RPM torque than high RPM horsepower. This is the type of cam that would be used in an RV if you wanted to upgrade the motor. __________________ Tim

11-15-2002, 08:53 AM	#3
BLACK AND BLUE 67-72 Firefighter Join Date: Feb 2001 Location: Yellville, Ar, USA Posts: 1,943	No, it's just designed for RV'S and heavy duty towing so they call it an RV cam. __________________ '72 Chevy SWB 350 Auto '67 GMC LWB 350 4 speed '70 Chevy 4x4 Stepside 350 Auto Yellville, Ar. USA

11-16-2002, 01:18 PM	#5
ckhd Registered User Join Date: Oct 2000 Location: St. Johns, Arizona Posts: 2,660	There aren't truly RV cams. It's a generalization of a type of cam profile. If the cam is designed to pull, have low end torque, etc... then people will generalize it as a "RV" cam. The cam I have in the '68 has been generalized as a "RV" cam, but when I bought it, it bought it for it's rpm range and torque aspects. It's the same as a "3/4 race" cam. Really no such thing, but if it has tall lobes, and makes lots of horsepower at high rpm, but can still be driven on the street (with the idle cranked up to 1200rpm or something), then they call it a "3/4 race". If you want a smart parts guy to take advantage of you, ask him for a "RV" or "3/4 race" cam. If you want what you need, call a cam manufacturer and give them the specifics of your engine (ci, compression, head flow, valve size, rocker ratio, intake/exhaust manifold type, carb info), vehicle, etc.. and tell them what you will be doing with the vehicle, and they will help you pick the right profile for your application. I'd say that Crane probably has at least 6 grinds that could be generalized as "RV" cams, and probably twice as many that could be called "3/4 race" cams. If you have Desktop Dyno, you can plug in all of your engine specifics, including all the details of your cam, and see if the cam will do what you want. The cam is the heart of your engine. Pick the wrong one and you'll hate your engine. Pick the right one, and you'll love it. __________________ my 2¢ - t.i.o.l.i. Bowen 1968 K20 fleet 1969 K10 swb fleet 1972 K10 Suburban 1972 C10 lwb step 1992 K1500 'burb 1995 K2500 'burb 1997 C1500 'burb 1999 K1500 2000 K1500 'burb Why do I own so many Suburbans?

11-16-2002, 09:03 PM	#8
lukecp Formerly yellow72custom Join Date: May 2001 Location: Austin, TX Posts: 7,531	I always thought of a RV cam as one with 204/214 degrees of duration @.050 lift, and around .420-.440 lift. BTW, i have one in my truck and i am very happy with it. However....the power drops off considerably above 4500 RPM, but it runs really strong everywhere else. __________________ '72 Chevy C10 Mild 350/TH350/3.07. Ochre/White. Old high school ride. '70 GMC C2500 '62 327 4bbl/SM465/4.56-geared Dana 60. White/White. Project or parts truck. '97 Saturn SL DD. 1.9/5-speed. 40+ highway mpg

11-15-2002, 12:37 PM	#4
RON WOODGEARD Resident Young Old Dude ! Join Date: Jul 2001 Location: Nevada Posts: 1,948	BLAZER 1970 is right! An RV cam is a cam designed to be useful in the lower RPM range.. My pulling cam (RV CAM) is actually a pretty good street performance cam. and along with an AUTO, RV TORQUE CONVERTOR,LOW range manifold & carb set up,GEARS, ETC.ETC. My 350 was a very strong pulling engine. I pulled a 4 horse bumper pull horse trailer. MY CAM SPECS, DURATION, 272/282 LIFT, 442/465 112 center line Useful RPM: 1500-5000 TORQUE: 0-3500 RON

11-16-2002, 05:00 PM	#6
RON WOODGEARD Resident Young Old Dude ! Join Date: Jul 2001 Location: Nevada Posts: 1,948	NO SUCH THING AS A 3/4 RACE!!!!!! Not any more, but to us old farts???!!! this was the way in which we bought a CAMSHAFT. Before the extended technology there were VERY FEW cams to choose from IE: The race anology, 1/4,1/2,3/4,5/8,and fullrace. And I absolutely agree that a poor cam will really ruin your day, But I guess I still have more trust in a good cam company. You tell them you want an RV cam, and they will take it from there to ask the questions of it's intended usage at what RPM.Weight of vehicle,rear end gearing,Standard or auto, ETC,ETC, You can do most of the research yourself by getting the camshaft spec sheets. they will tell you what rpm the cam is intended for, as far as H.P and TORQUE. I don't know of a major name cam. company that doesn't offer that information to you. If you are going to really pull with it then you don't care about HP you want brute torque, at the lowest possible RPM. But don't plan on any CAMSHAFT working in the low rpm range and not having everything else "MATCHED" (in other words don't use a cam. that's intended for 0-3500 rpm and install a manifold, carb. combo. that works from 2500-6500 rpm. No 3/4 RACE CAMS anymore,???,,, Damned I am getting old. RON



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.