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Need help picking a cam

Old 08-13-2012, 06:19 PM
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Need help picking a cam

Ok so I'll apologize upfront for the vague description.

Its a hydraulic flat tappet cam motor. 350 4 bolt chevy from the 70's. The heads have been done up some, they look fresh, has valve guide plates from comp enginering. The previous owner bought it with a hot cam, took it out and re-installed new mild cam and lifters.

I'd like my new cam to be on the wild side, lopey idle but does idle, and a decent rev range probably under 6000. Mpg doesnt matter. Preffer to have semi budget cam. This will be for strip/street car.

Any suggestions?
Old 08-13-2012, 07:08 PM
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Re: Need help picking a cam

WILD cams sound cool but usually not very streetable. anything over about 272 duration and youll need a stall. more info would probably help. headers? carb? intake? what lift are your springs rated to? etc?
Old 08-13-2012, 07:28 PM
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Re: Need help picking a cam

4 barrel 600 cfm edelbrock carb, and I think its a performer intake. Exhaust work only done from catalatic converter. Stock stall with swapped in 3.42's.

Sadly I do not know ANY specs about the engine (besides in op). It looks recently rebuilt, and like they did some performance type work on the heads. The guy said it HAD a performance cam in it, which he took out for milder one.

I will do headers and finish exhaust, get bigger stall and lower gears in the future, but it might take a year or so. I'd like to have a strong enough cam in it that im not bored with the motor once the other work has been done.

What do you think about this? http://www.summitracing.com/parts/SUM-1065/

Says it will work with stock convertor, not super high revving, right at 272 duration and likes 9:1 compression (not sure on motors compression)
Old 08-13-2012, 08:31 PM
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Re: Need help picking a cam

IMO, that cam is just a tiny bit smaller than what id try. but smaller is better than bigger for the street. there is a big difference between advertised duration and duration at 050. basically,...add 50 to the duration at 050 and youll have a true reading. advertised duration dont mean squat. so the summit cam you posted would have a real world duration of around 266. you could probably go up 1 or 2 more sizes, in theyre catalog. but the cam you mentioned would be great on the street and not need an aftermarket stall. dont forget alot of todays oils dont have ZDDP in the oil. make sure you use the correct oil for your cam. i like valvoline 1 racing oil. some like rotela, etc. youll ruin that new cam in no time without the right oil.
Old 08-13-2012, 08:56 PM
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Re: Need help picking a cam

I knew you had to have special break in oil, but will I need the ZDDP type after break in?

http://www.summitracing.com/parts/SUM-1785/

This looks like its just a little bit more then the previous posted cam, and says will work with stock stall.

Or this one, http://www.summitracing.com/parts/SUM-1788/ Says it needs 2000+ stall, but isnt my stock convertor around 1600 anyway? So will it still work, and just wont be fully utilizing the power until I upgrade.
Old 08-13-2012, 09:56 PM
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Re: Need help picking a cam

Usually an erratic idle and a streetable setup don't go hand in hand too friendly.

You can compensate by adjusting your idle down a little with a smaller cam or you can run one of Comp Cam's Mother Thumper cams... just to warn you that you'll sacrifice some power for sound. Or alternatively run a cam with a lower numerical lobe separation to get the rough idle you desire. I don't go lower than 110 LSA on a street car but some guys go down to about 106.
Old 08-13-2012, 10:15 PM
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Re: Need help picking a cam

I care alot more about power then sound. I want as much power as I can get with still being able to drive it on the street.
Old 08-13-2012, 10:19 PM
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Re: Need help picking a cam

Originally Posted by blue birdy 87
I knew you had to have special break in oil, but will I need the ZDDP type after break in?

http://www.summitracing.com/parts/SUM-1785/

This looks like its just a little bit more then the previous posted cam, and says will work with stock stall.

Or this one, http://www.summitracing.com/parts/SUM-1788/ Says it needs 2000+ stall, but isnt my stock convertor around 1600 anyway? So will it still work, and just wont be fully utilizing the power until I upgrade.
id use the 2nd cam you listed here. yes you will always need ZDDP oil,...even after break-in. id get a cam and lifter kit. obviosly dont use old lifters on a new cam. you should be o.k. with the stock stall. probably a good idea to get some new valve-springs too. some cheap Z-28 springs should do the trick. any bigger and youll need an aftermarket stall. im only using a 268 cam and it lopes nice with its low idle, very streetable, will run to 7,200rpm,....great street manners and vaccuum. without starting a debate,..you can switch to 1.6 rockers later and efectivelly increase duration and lift a lil if need be.
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