AzCoupe":10wfgj6r said:
I have spoken with four different cam manufactures, including Isky when we were at SEMA last fall. All suggested a dual pattern cam in applications using the OZ heads or Offy trips due to the increases in CFMs on the intake side. Applications with the stock log and a single carb would not see much benefit in dual patterns.
AzCoupe":10wfgj6r said:
Designed especially for the small sixes with modified (increased) carburetion. Specifically the OZ heads, Offy triples, and large duces as they offer more CFM than most shelf cams were designed to handle. Dual pattern for better exhaust capabilities.
Adv 268/274, 208/218 @ .50, .453/480 lift, 108° lobe centers.
Good vacuum, lopey idle, RPM range 1500-5800, can run higher compression due to smaller lobe centers (lowers cylinder pressure) they recommend minimum 9.4 CR, suggest 2000-2400rpm stall with auto trans. and a minimum of 3.20 rear gears (preferably 3.50). Durations were kept low to maintain low-end torque, lobe centers give more midrange, higher lift yields better overall and top end power. Said the cam should work really sweet for a daily performance driver.
I can have these ground to any specs I want, so if you want to make changes, feel free to e-mail me with what you want. If I order on Monday, I can have it by Friday. They are working on a hotter shaft for more top end performance and for use with manual trannys only. Have also requested a cam that is a bit milder for those of you who are so inclined. Remember, these shafts are being designed to optimize the additional CFMs that we are adding to the intakes, while still maintaining the fairly restrictive exhaust. The idea is to make the most of what we have to work with.
AzCoupe":10wfgj6r said:
This cam was designed with a C4, 2000 stall converter, and 8" 350 gears in mind.
Mike,
I went back to some of your old posts to answer some of my questions first. So I assume the cam specs above are for the log heads. The dual pattern cam is still the hot ticket for those of us with Aussie heads. I thought the one you had listed in your previous post (above) might be a little aggressive for my purposes (daily driver, beach curser, freeway flyer). I’ve been playing with some numbers on a custom grind: (
262/272 206/216 .425/.445 109 – 1500-5500) based on these engine & drive train specs:
Carb - 350 Holley 7448 2bbl on adapter.
Ignition, Pre '68 distributor w/Pertronix module (must ensure that vacuum advance is operating on early pre-68 distributors) w/Pertronix flamethrower coil.
Cylinder head 250 2V head with 1.75" SS intake valves and 1.5†SS exhaust valves, Hardened valve seats, 5/16 bronze guides three-angle valve grind, pocket ported, exhaust port divider installed. Aftermarket valve springs, adjustable rockers, mill the head to the desired compression ratio (8.9:1 to 9.2:1) ARP head bolts (one reduced shank head bolt on the Driver's Side rear-most bolt hole from a 75-80 Fairmont) with hardened washers and a steel shim head gaskets (.025â€).
Bottom end - 200 block decked to zero, use the stock dished piston, Molly rings, ARP rod bolts, balance the rotating assembly, and Dual Roller Timing Chain.
Cam, custom dual pattern cam. ?????????
Oiling system - Baffled oil pan with windage tray.
Transmission, C4 Auto trans w/2000 stall converter
3.50:1 ratio 7.25" four lug
rear end.
Exhaust, single outlet headers 2 1/4" single exhaust system w/ Dyno-Max low-restriction Turbo muffler.
Opinions and recommendations on the custom dual pattern cam grind specs welcome. Sorry for the long post, but how about
the use of color 