Cam recomendation?(Rough estimate)

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gregsdart

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We are going to build a 408 street smallblock, 3.73 gears fourspeed, 10/1 compression, probably an airgap dual plane, heads yet to be determined, although if I can find a decent set, 318b aftermarket iron , or better. The goal is a motor that will idle with a little lump, pull between 10 to 14 inch vacuum, have excellent torque for street driving and some gas mileage (10?,12?) and maybe a power peak of 5200 to 5600? My WAG is something in the mid 220 range at .050, intake, another 6 to 10 degrees on exhaust, with an lsa in the 110 range? What have you run, and did it meet the goals i am after?
 
I had a 408 with a Hughes hydraulic roller in the 230 duration range that was good...no idea on mileage.
 

We are going to build a 408 street smallblock, 3.73 gears fourspeed, 10/1 compression, probably an airgap dual plane, heads yet to be determined, although if I can find a decent set, 318b aftermarket iron , or better. The goal is a motor that will idle with a little lump, pull between 10 to 14 inch vacuum, have excellent torque for street driving and some gas mileage (10?,12?) and maybe a power peak of 5200 to 5600? My WAG is something in the mid 220 range at .050, intake, another 6 to 10 degrees on exhaust, with an lsa in the 110 range? What have you run, and did it meet the goals i am after?
You can get a Lot more power and a lot more RPM than that with an expectation like 10 to 14 inches of vacuum and 10-12 mpg
 
One of the reasons i am conservative on my own guestimate of duration was i built a 408 with a thumpr 235/249/107 hyd roller, 318b heads,and the motor was a beast making 518 tq at 4600 and 503 hp at 4700, BUT, it had a rather ugly idle and needed a 4,000 stall converter. That cam had 28 degrees overlap at .050, and too much for our needs on this next 408. Obviously less cam will mean less total hp, but that is ok to a point. I mentioned something on the order of 225/235/108 might get me close? With 3.73 rear gears and a stock 340 4 speed, the ideal situation would be for it to not need a lot of rpm and clutch slip to get moving in a full weight 73 duster with a couple of passengers
 
If you want something custom, you could talk to Ken at Oregon Cam Grinding. He's got some pretty decent profiles for what you're wanting to do. Possibly some that will work on a stock LA or Magnum cam core.
 
The go to cam for customers wanting a stroker, but wanting it mild enough there wife can drive it, for me has been the comp 274 hydraulic roller. Have one in a 408 with trick flow heads, air gap ect, still running a stock converter.
 
The go to cam for customers wanting a stroker, but wanting it mild enough there wife can drive it, for me has been the comp 274 hydraulic roller. Have one in a 408 with trick flow heads, air gap ect, still running a stock converter.
If the QC is still acceptable on them, I don’t see any downsides to using one those for that application at all. If it’s as good as the XE 274H in a stroker then it’s about as good as it gets for a street cruiser.
 
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