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Here's what I have, 454 bored 30 over ,scat forged rods speed pro forged 2349f pistons 30 cc dome, brodix race rite aluminum heads 270cc 2.25 intake 188 ex,eldebrock rpm air gap 850 volley do with pro form valve body, headders this is a stick shift car, 1978 camaro, I need help picking a can for this, its a street strip car,I want as much power as I can get and still be drivable in town, thinking hyd roller maybe ?
 

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you can go a decent size cam,what do you call decent to drive on the street?What is the measured compression ratio? Im thinking 250 ish º duration @ .050 and low .600s lift with LSA of 110º-112º. This is just a guess to get the discussion started.

what are the head flow numbers?
 

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As long as it doesn't surge at lower rpm it would be fine, never put dome pistons in anything and these are closed chamber pistons with open chamber heads,little worried about the valves hitting
 

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It would be nice to have flow numbers so the cam matches the heads and compression ratio. BBCs need a little care when matching pistons and heads. Do you know the deck height of the pistons?You have to check piston to valve clearance on all cam changes(performance especially) You should check PtoV at 0&plus/minus 4º.
As far as gears are concerned,that is matched to the transmission and use of the car with tire size part of the equation,nothing to do with how the engine runs
 

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1.645" piston compression height, 6.135" rod, 2.000" crank radius makes a 9.780" stack. Airflow Research recommends a Fel-Pro 1017-1 head gasket for use on a 454 with aluminum heads, 4.540" x 0.039", so for engineering a 0.045" squish/quench, after verifying that the mains are round and parallel with each other, cut the block decks to a new block deck height of 9.787", allowing a piston deck height of 0.007" and a squish/quench of 0.045" with the 0.039" head gasket. Assuming the combustion chambers at 119cc's, this combo allows a static compression ratio of 10.4:1, right at the max SCR currently advised for aluminum heads on pump gas. Trial assemblies with clay will be necessary to validate piston to head clearance as well as piston to valve clearance and of course any cutting on the head or the piston crown will lower SCR from the calculated 10.4:1. Use only oil-based modeling clay from the hobby or craft shop, Play-Doh will not hold its shape properly for accurate measurments. Ask me how I know. Iskenderian rents piston notching tools that operate in the valve guides with your drill motor so that the cuts are dead nuts for the heads used. Part number PNT-238 would be 2 3/8" diameter for the intake valve and part number PNT-200 would be 2" for the exhaust valves.
http://www.iskycams.com/
I have made my own cutters in the past by sweating a cutting tool to an old pair of intake and exhaust valves.

Use Howards CL120255-12 retro-fit hydraulic roller cam with lifters kit.
Advertised duration 284/288
0.050" duration 231/235
Valve lift 0.578"/0.618"
Intake valve centerline 108 degrees
Exhaust valve centerline 116 degrees
Lobe separation angle 112 degrees
Fair idle, Performance usage. Great mid-range torque & power.
Operating range 2400-6000 (hydraulic roller lifters are heavy and will begin lofting up off the cam lobes at speeds above 6000 rpm's. Use a rev kit if necessary). To my surprise, Howards does not make a rev kit for the BBC, but Comp does....
http://www.summitracing.com/parts/cca-4003/overview/make/chevrolet
I would use a 10", 3000 stall converter and some serious gear in the diff, along with upgraded rear suspension components, diff locker/no-slip and some serious tire. I might be thinkin' tubs or mini-tubs.

This combo makes 10.4:1 SCR, 0.045" squish/quench and 8.73:1 DCR.

If I get a chance later, I will put this combo into DynoSim and see what it produces. I'll need some reliable head flow figures, 0.100" through 0.700" valve lift, intake and exhaust. I have the cam timing events at 12.5 BTDC,/43.5 ABDC/53.5 BBDC/1.5 ATDC @0.050" tappet lift.

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Cylinder head flow figures can be found at the Stan Weiss Cylinder Head Database....the are listed as "Brodix RR BB-O" (Brodix Race-Rite BigBlock-Oval)
Stan Weiss' - Cylinder Head Flow Data at 28 Inches of Water -- DFW / FLW Flow Files for use with Engine Simulation Software

Stan's database has flow figures for literally a thousand heads, or more!
Bookmark the site, it gets updated as people add figures for new heads. (Here you go, Techinspector!)
Stan Weiss' - Cylinder Head Flow Data at 28 Inches of Water -- DFW / FLW Flow Files for use with Engine Simulation Software
 

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As long as it doesn't surge at lower rpm it would be fine, never put dome pistons in anything and these are closed chamber pistons with open chamber heads,little worried about the valves hitting
Closed chamber pistons in open chamber heads is no problem, you just can't go the other way around.
It is dome shape interference with head chamber shape that causes the problem, not anything to do with the valves.

Cam size is going to determine valve-to-piston clearance and not the fact that you are using closed chamber pistons with open chamber heads, both the open chamber and closed chamber pistons have the same valve reliefs, and open and closed chamber heads have the valves in the same place and depth also.
 

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agree with techinspector on his post( I would use the bigger cam)

as far as gears are concerned,thats a choice you can make based on tire size and expected ETs. The transmission you have will need some help if its a stock unit,that soon to be 454 beast will be breaking drive line parts in that super heavy car. Try and drop at least 300 pounds,,,
 

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Motor wanted more cam. Not finished yet, but made 565hp @5500 and 585 ft/lbs of torque @4500 with Howards CL120275-10, installed 3 degrees retarded. Will try a few different cams later this evening. Great heads!!!

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Howards CL120275-10 Hydraulic Roller Retro-Fit
Installed retarded on these 0.050" tappet lift numbers....
Intake opens 11.5 degrees BTDC
Intake closes 49.5 degrees ABDC
Exhaust opens 51.5 degrees BBDC
Exhaust closes 9.5 degrees ATDC

RPM....HP...TQ
2000 176 472
2500 223 468
3000 283 496
3500 359 539
4000 435 571
4500 500 583
5000 548 575
5500 567 542
6000 555 486
6500 488 394
Max volumetric efficiency 98.6% @5000
Max BMEP 190.8 psi @4500


Howards CL121615-14 Hydraulic Roller Retro-Fit
Installed retarded on these 0.050" tappet lift numbers....
Intake opens 7.5 degrees BTDC
Intake closes 55.5 degrees ABDC
Exhaust opens 61.5 degrees BBDC
Exhaust closes 13.5 degrees ATDC

RPM....HP...TQ
2000 168 441
2500 215 452
3000 268 469
3500 341 512
4000 418 549
4500 485 566
5000 543 570
5500 576 550
6000 580 507
6500 546 441
Max volumetric efficiency 104.5% @5500
Max BMEP 186.7 psi @5000

Notice that although the bigger 121615 cam makes more max hp at a slightly higher rpm range, the shorter cam makes quite a bit more power and torque from 2000 to 5000 than the bigger cam (more power under curve). For a street motor, the 120275 cam would be my choice. It's only 17 away from 600 ft/lbs at mid-range rpm's. MISTER TWISTER.

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