Author Topic: cam shaft recommendation  (Read 2555 times)

Offline billy 2

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cam shaft recommendation
« on: January 16, 2013, 06:21:24 AM »
Looking for recommendations for a camshaft.  I am building a 427 c.i. big block Chevrolet engine. 
Bore is 4.90(.040 over)
Stroke is 3.76
Compression is 9.5(forged pistons)
Heads 1965 Chevy oval port closed chambered (iron)
Intake valve 2.60
Exhaust valve 1.72
Looking for a hydraulic roller camshaft that will work well with this combination and will use pump gas.  Hoping for a lobe separation 110-114, so I can get good idle and good vacuum.  Has anyone had any particular luck with that combination?  This engine will be going into a 1967 Camaro, 4-speed, 355 rear end gears.  Haven't decided whether to use headers or stock manifolds.  The reason for the engine change is that I decided to drive the car more in the future.  I restored the car 20 years ago.  It was completely original with the original engine with 10.5 to 1 compression.  It doesn't like the fuel we get from the pump today.  It's getting too expensive to buy 112 octane racing fuel to drive on the streets.  So, I was hoping to replace the original 396 and use the 427.
Thanks, billy 2

Offline Cliff Ruggles

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Re: cam shaft recommendation
« Reply #1 on: March 18, 2013, 05:34:43 AM »
The camshaft is the key to managing pump fuel.  I'd be looking at something around 222-228 degrees at .050", 280-290 advertised, on a 112LSA.  Avoid 110 or tighter LSA.  The big 427 and manual trans application will be fine with a larger cam in it, and larger cams reduce dynamic compression, making it easier to effectively manage pump fuel.....Cliff

Offline billy 2

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Re: cam shaft recommendation
« Reply #2 on: April 19, 2013, 07:16:27 PM »
 Well Cliff I changed a few things since my last post. I decided to get a set of .040 over 454 flat top pistons and use a 454 crankshaft we had laying around that had just been ground 20/20. Use everything else that I mentioned in my earlier post.  The camshaft selection that I am going to use is a hydraulic roller from Comp Cam.  Valve lift intake .511, exhaust .521, duration at 50 off, intake 230, exhaust 236, lobe separation of 112.  Just finished putting it together, have a few small pieces yet to pick up and then I hope to be able to set up some time to get it on an engine dyno to do the engine break in and do the tune up on the engine.    billy 2

Offline Cliff Ruggles

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Re: cam shaft recommendation
« Reply #3 on: April 28, 2013, 04:30:19 AM »
Good cam choice, let us know how it does?.....thanks...Cliff