Author Topic: Cam question  (Read 6282 times)

Offline Maintenanceman

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Cam question
« on: February 27, 2009, 05:08:02 pm »
Need a little help guys as I know nothing about picking cams. Ive got a SBC 350 with a holley intake, Holley 600 CFM carb and headers. Im looking for more towing power. Everyone I talk to says to go with an RV cam. Well thats all fine and dandy but I cant seem to find any info (maybe im not digging hard enough.) Where do you buy RV cams and do they come in different sizes? The engine has around 25k on the clock and is only about 5 years old. Will I need new springs? I will buy lifters for sure but what about pushrods? Will the stock length work?

TIA
Ben
1985 Silverado K20- 355 SBC Vortec heads and a lil' cam...

Offline joesgarage71

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Re: Cam question
« Reply #1 on: February 27, 2009, 06:28:10 pm »
Ben,
 What gears do you have?
 Heres a little reading
http://home.comcast.net/~rhodes/camshaft.html
« Last Edit: February 27, 2009, 06:32:29 pm by joesgarage71 »
78' K-20 355/SM465/twin stick 205 6" on 36's
14 bolt FF/big bearing Dana 44 4.56 gears

92' GMC C-1500 454/4L80E/14 bolt

Offline Maintenanceman

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Re: Cam question
« Reply #2 on: February 27, 2009, 07:17:23 pm »
3:42's
1985 Silverado K20- 355 SBC Vortec heads and a lil' cam...

Offline Maintenanceman

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Re: Cam question
« Reply #3 on: February 27, 2009, 07:30:58 pm »
Lotta info there thanks alot! but where can I buy the RV cam?
1985 Silverado K20- 355 SBC Vortec heads and a lil' cam...

Offline VileZambonie

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Re: Cam question
« Reply #4 on: February 27, 2009, 08:19:39 pm »
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline Lt.Del

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Re: Cam question
« Reply #5 on: February 27, 2009, 08:40:48 pm »
I love my RV cam, takes advantage of the lower rpms of the engine.  She also has a mild lope in idle.  With duals, she sounds awesome.   

Offline Blue 82

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Re: Cam question
« Reply #6 on: February 27, 2009, 10:38:11 pm »
Keeping your intake lobe duration between 200 and 210 degrees @ .050" should be in the ball park

These guys have always treated me well
http://www.reedcams.com/index.html

Here's some off the shelf cams
http://www.reedcams.com/cam_SBC_street_hyd.htm

Here's some more
http://www.reedcams.com/hyd_flat_profiles.htm#anchor1

If you want max torque at a particular RPM for towing, give em a call
Give specs on your heads and compression ratio
They will set you up. (you will be talking to the guy that grinds cams, not a tech line flunkie)

(ps, they don't sell chinese/offshore crap)
82 stepside 2wd 355/th350/3.08 posi

Offline eventhorizon66

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Re: Cam question
« Reply #7 on: March 01, 2009, 06:39:54 pm »
I don't think anyone has specifically answered your question on what an RV cam is.  But, so you know, a cam in the size range that Blue 82 mentioned at the top of his post would be considered an "RV" cam (I might extend that range to 215° @ 0.05").

As far as I can tell, "RV" is mearly a term meaning a cam slightly bigger than stock but still oriented around low-end torque, suitable for a truck or RV motorhome.  Also some say RV means "really varies," but I think the first makes more sense.
« Last Edit: March 01, 2009, 07:45:05 pm by eventhorizon66 »
'85 C10 SWB 350 700R4 TKO600

Offline kiowamec

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Re: Cam question
« Reply #8 on: March 04, 2009, 01:05:24 am »
http://www.northernautoparts.com/ProductModelDetail.cfm?ProductModelId=4251

I have used this cam kit, it has a slight lope at idle.
It does not require new springs. I put it in a stock engine that a had a wiped cam.
Combined with some used 3.42 gears the car went from a junker to fun to drive.


Offline mike_hd1340

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Re: Cam question
« Reply #9 on: March 14, 2009, 10:50:34 pm »
If your just wanting a little more towing power you need to look at something like the comp high energy series cams.  There good for low end torque and with 3:42 and only a 600 carb you don't want to get to carried away.  I would look for something around a 200-210 duration @.050 and 420-440 lift.  As far as valve springs you can use the stock springs with these smaller lift cams,  but you would be much better off to buy the entire cam kit with the macthed springs and lifters.  It cost a little more but,  will save you money in the long run.
« Last Edit: March 14, 2009, 11:21:09 pm by mike_hd1340 »