Debating on a head and cam swap on the 318

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cross_thread72

cross_thread72

Tattooed white trash
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In a recent trade I inherited a set of 920 casting heads, they need freshened up a bit but already have 1.81" valves and have a decent looking closed chamber, I'm planning the standard 3 angle valve job, and a good resurfacing. I also got some of the "white performance" stainless roller rockers in the deal too. I'm running a weiand dual plane intake, a Holley 650 double pump (spread bore) with a 4 hole 1" spacer, and will be adding headers while its apart. It has a mild cam of unknown specs in it now and pulls fairly hard until 4800-5000. I'd like to go ahead and swap cams while its apart. Anybody have a suggestion for a hydraulic flat tappet that will work well with these heads and intake? The heads have roughly 62-64 cc chambers and I've got some head gaskets that are .040 thick and have a 4.060 bore so it might wind up with decent compression. And please keep the "throw away the 920's and get some magnums" comments to yourself. From what I've read they out flow the 302's and some superstock say their a desirable casting.
 

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more info about your combo would help.like gearing and converter stall speed.also if you need vac for power brakes.if you can live with or like a rough idle id run an isky 270 mega cam.a step up from that would be a schneider cams 284h cut on a 108 lsa.a nice all around street grind is the crane powermax 278.it idles well with good vac and has a very broad flat torque curve.
 
I'm not real sure what the gearing is now, and the converter foot brakes to around 2k I've had it flash around 2400, idle quality isn't a concern nor is vacuum. The headers I have are the typical 1-5/8" with 3 inch collectors. I'm also running an MSD 6AL, with a pro billet distributor w/o vacuum advance. I also forgot to mention I'm running a 150 shot of nitrous. I'm planning on a gear change in the near future but it won't be anything higher than a 4.10
 
personally i like tor run custom grinds form crower,isky or schneider. schnerider 284h or 280/90h,or an isky 270/80 mega.the crane i mentioned would also work well and have good street manners,but probably not have as much mid range as the others.
 
Easy,Ultra Street Beast,Crower.269/282 adv,at.050:223 int,234 exh.486 lift,int,.501 on exh.112 lobe centers.Pulls mid 6k,pocket ported heads,3.91s/4.10s.Loves nitrous,an understatement.Ran 3 of these myself.The best ,I seen one E.T.,12.20s@ 116 on spray,tons of tire slippage on slicks.
 
Abodybomber said:
Easy,Ultra Street Beast,Crower.269/282 adv,at.050:223 int,234 exh.486 lift,int,.501 on exh.112 lobe centers.Pulls mid 6k,pocket ported heads,3.91s/4.10s.Loves nitrous,an understatement.Ran 3 of these myself.The best ,I seen one E.T.,12.20s@ 116 on spray,tons of tire slippage on slicks.
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good choice as well. almost identical specs to the crane i mentioned.
 
Stock form the 920 heads ,as most 318 heads, peak flow at around .450 lift...so going to/around .500 lift is a good thing to make up for lag time/and basically put the peak flow in the longer mid lift open close cycle since full lift is mearly a blip when it comes to time spent there.
 
What about some minor port work? A buddy of mine is a well known porter locally, he's done all the head work on diesel power magazines "project x" which holds multiple records, he's volunteered his services, but I'm afraid too much port work will kill it in the low/mid range. We cc'd the heads and they're 57cc's and after surfacing they'll be around 53 cc. He wants to cut them until the deck surface hits the intake seats, and hog the ports as far as he can without them breaking through. In theory that sounds great for an all out drag motor, but not so much for the street. Does anybody have a real world opinion or experience with a cam similar to the crower mentioned, with a head like the 920? Should I go ahead and use my free porting card for these heads, or save it for a rainy day and just freshen them up and slap them on?
 
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