Okay I am building a street engine only. Clifford intake/headers,4barrel carb.Going in my 58GMC 1/2ton truck. Should I have the cam reground or go with a nos? Would I save any$$? Opinions.... Thanks,
If you are adding headers and intake, its kind of a waste to not take advantage of increased breathing via a better cam. personally, I am leery of reground cams. What does Clifford 6=8 offer? Or Langdon's for that matter. Edit: http://www.langdonsstovebolt.com/store/#!/Bulldog-GMC-Camshaft/p/33580040
I would be happy to help. But the last new GMC cam I bought was from Chuck Potvin. Don't think he is working these days. I understand Dema Elgin has retired. I don't mind a reground cam as long as the surface remains the correct hardness. pick a grinder you trust.
If you have a stock cast cam most cam grinders can regrind it for more lift and duration and you can still use the stock lifters. Stock cam lift is close to .270" and the rocker ratio is advertised at 1.5 but it's closer to 1.4. Bullet cams in Mississippi have every grind you can think of (they have charts on their website) and you could ask them if they would regrind yours and recommend one for your application. A steel cam is very costly and not needed for what your doing. 302's are stump pullers and advancing the cam a few degrees can help make it even better. Good Luck.
There's a guy that has nos stock cam& performance steel howard F290/108 3/4cam. Just not sure. Machinists likes Delta(?).Original question-reground or buy new? Yes the plan is to still use stock lifters also. I am just putting in a 1/2ton truck for cruising Sent from my iPhone using The H.A.M.B. mobile app
Well Jim and I agree that a reground should be fine. So I guess you want to hear "Buy new". If that is what will make you happy, go for it.
WHAT compression and gear ratio? Head work? I LIKE the concept of dual-pattern cams, with more duration on the exhaust side. Look at SCHNEIDER CAMS site for 250-292 sixes, to get an idea of RPM ranges and differences in duration. Talk to Jerry there. Tom Langdon would also offer good advice. The LATER the intake valve closes, the MORE compression you need to keep power and throttle response up. Keep the valve OVERLAP to a minium for good driveability on the street. Lumpy cams sound cool, but are a PITA to drive around town. BUT... you could run a larger cam than what one would choose for a 235/261, as you are working with more displacement, more inhearent TORQUE. A lumpy cam in a small engine would be alot smoother in a larger mill. SO... I'm thinkin' with 9-9.5 compression, a dual-pattern stick, 264 intake / 270 exhaust... maybe a little more, depending on compression and induction. Lift is whatever they can get from regrinding your core. Send your lifters in with the cam, and they can reface them too, for 1/2 the cost of NEW. I'm not familiar with GMC heads, but I would look at the ports below the valve seats - how much material is there. The last 1/2" of the port above the seat is most critical for flow - should be around 80% of valve size. Most shops refer to this as POCKET PORTING, much more cost effective than a full-on port job. You can even do this yourself with a die grinder, and a couple old valves cut down as checking plugs. Let us know what 'stick' you pick! Good Luck, Tim
Not necessary wanting to hear buy new. Didn't know cost differences .I pointed out that my machinist likes Delta Cams. Didn't read any comments on that company. I'm for saving if even possible, as gmc stuff isn't as easy to find-so it cost more when parts are found.....BTW: never got parts from Patricks so I got burned there also....
I never have had a Delta cam. I have used Americam. ( think that's the spelling) He does good. Have you called Isky? Sorry to hear about Patrick's. Bummer.
Can't remember everything on the Howard's but their first # was the cam lift on many. The steel cams also called for chilled iron lifters which were stock on 1939 Chevrolets and the stock steel cams the GMC's used in the military. A cast iron cam maybe a better option as many GM and after market lifters are available. Steel cams also like to eat up distributor gears if not oiled properly which is pretty easy to do with a feed fitting located on the block. Cast cams did not have this problem. Good Luck.
Langdons prices are for reground with you sending a core. Sent from my SM-G550T using The H.A.M.B. mobile app
Wouldn't the most efficient way to get the answers to this and other questions you have asked, be to call people who grind cams? I have set records with reground cams from Crower and Dema Elgin. They have phone service. I know the regrinding diesel truck cams is a very profitable business. And they run for lots and lots of miles. So it can't be to bad a process.
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