Thread: Help me find my cam - 396, oval port heads, 10.1 compression

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Originally Posted by Jason_Lyman

It will be driven - not a trailer queen.

Great, then let's use some street driver parts, not race parts.

Originally Posted by Jason_Lyman

I'm not looking to build the fastest street car in America. I just want a stout motor that will "get the job done".

Great, I'll do my best to help you achieve your goal.

Originally Posted by Jason_Lyman

I plan on running a 2000-2300 RPM stall in a Turbo 400. I want a motor that comes to life around 2K RPMs and goes up to 6K RPMs. I don't really want to push it much higher than 6K RPMs.

You're going to need to begin stalling at 2800-3000 in order to use a cam that will make power up into the range. There is an effective range of about 3500 rpms or a little less for any cam that you bolt into the motor. For this application, I would use a cam that begins at about 2000 and noses over at about 5600, then use a 10" converter that comes on about 2800, giving you an 800 rpm lead on the motor, so that you're making hp when the whole mess hooks up. A 2800-3000 stall converter is a sweetheart on the street. Easy driver.

Originally Posted by Jason_Lyman

Lower end of motor is complete. 4 bolt main, forged rods and pistons. 10.1 compression. Very nice balance job.

A street motor at 10.0:1 with aluminum heads is just about as good as it gets, just make sure you use a composition head gasket so that the heads have a little wiggle room to prevent fretting. What did the squish/quench figure out to?

Originally Posted by Jason_Lyman

Heads will be AFR Magnum heads. 265CC runners. Oval port.
265cc BBC Oval Port Cylinder Head - Air Flow Research

Best BBC street heads on the planet.

Originally Posted by Jason_Lyman

Intake will be one of the following (still figuring this one out).
Edelbrock RPM
Edelbrock RPM air gap
Weiand Stealth

Stealth

Originally Posted by Jason_Lyman

Sorting out ignition. For now, let's just say HEI style with a super coil.

DUI

Originally Posted by Jason_Lyman

Carb: I have a Holley 750 that was modded years ago to allow all 4 barrels to open simultaneously. I had this carb on a pretty wild small block. It was a very touchy carb and I loved it. Debating if I need to go with a larger carb or jet this one way up for the big block.

I would adapt an 800 CFM Quadrajet to the Stealth.

Originally Posted by Jason_Lyman

Rear end: 12 bolt posi with either 3.55 or 3.73 gears. Also, still sorting this one out.

You have enough cubic inches to pull, I might use the 3.55's with the 2800-3000 converter.

Originally Posted by Jason_Lyman

I've already read several posts in here about big blocks being nasty to cams and that a roller is recommended. I had already decided roller was what I wanted, info here has cemented that plan. I just don't know which cam to go with.
So... recommendations on a cam that's going to make for an engine with great low end and mid range oomph for a stoplight to stoplight killer?

I like Howards. They're reasonably priced, have a good reputation and have been grinding cams since Noah was a teenager.

Part number CL123315-08 cam and roller lifters. This cam was chosen for performance, not for intake manifold vacuum. Vacuum brakes could be problematic. A change to all-around non-vacuum disc brakes would be the best fix. This cam has a lobe separation angle of 108 degrees for max power. If you need to adjust to less power with more intake manifold vacuum, have this cam ground by Howards with a 112 degree lobe separation angle.
2000-5600 rpm operating range
Advertised duration 280/280
0.050" duration 227/227
Valve lift 0.555" / 0.555" with stock ratio rockers
Intake centerline 104 degrees
Exhaust centerline 112 degrees
Lobe separation angle 108 degrees
Hydraulic Intensity 53
Mild, rough idle, Hot street, must have good exhaust system. Use an X or H pipe immediately after the collectors.
Howards calls for a 2500+ torque converter (meaning 2800-3000)
Cam requires minimum 9.5:1 static compression ratio

Originally Posted by Jason_Lyman

And yes, I do plan on taking it down a 1/4 mile to see what ET I can get. Low 12s would blow me away!
Thanks,
Jason