Help pick a cam - HR for a BBB 482

[70GS455]

Please help with cam selection, I would like a hyd roller. Engine is a BBB stroker, 482 ci, 4.35" x 4.05", 6.8" rod. Application will be mostly street, 6000 rpm hard limit due to block strength limitations (no girdle), vacuum brakes, 4-speed manual, 93 octane. AL stage-1 heads have been ported and flow 325/235 @ .60" (340/250 @ .80"), 2.125", 1.75" valves. Edel B4B dual-plane manifold, port matched with mod'd divider. 10.6 CR, 1-7/8" or 2" headers. Springs are 145/365 #, 1.6 rockers Johnson HR lifters. The cam core has structural limits on open spring pressure at about 375#. This particular engine family is sensitive to valve train stability due to it's small cam tunnel and therefore finished lobe and base circle sizes. I was thinking something along these lines:

290/237, .575" int
298/244, .600" exh
113 LSA, +5 deg adv

Thoughts?

[427dart]

What car, weight and rear gear ratio? With a 3.55 I would add another 10 degrees @.050 on a 110 or 112

[blykins]

Where do you want the peak hp rpm to be?

[70GS455]

What car, weight and rear gear ratio? With a 3.55 I would add another 10 degrees @.050 on a 110 or 112

3850 lb car, 2.99:1 M23Z, 3.31 final

[70GS455]

Where do you want the peak hp rpm to be?

Before 6000, say 5700 to 5900?

[blykins]

Do you know the intake port volume by chance?

[70GS455]

Do you know the intake port volume by chance?

No, but I wlll check. I know they are smaller compared to other engine families.

[70GS455]

Do you know the intake port volume by chance?

260 cc

[blykins]

Ok, I've never been one to subscribe to the fact that there aren't certain specific nuances to different families that may/may not require a tweak to a cam spec. Someone here may specialize and have more experience in the Buick stuff and can lend more information. I have built a whopping zero Buick engines, so my specs are based on my experiences with other engine families.....mostly Fords.

Based on your desires, rpm requirements, the head flow, port volume, intake flow, exhaust flow, intake/exhaust flow ratios, displacement, vacuum requirements, etc., I'd be at:

293/301, 239/247 @ .050", .606"/.619" lift at 1.6RR, 114 LSA on a 106 ICL. It would have 69° of overlap, which should still operate your power brakes. Lobes are not aggressive (I have ran these lobes on some of my Clevelands with a 1.73RR and they are quiet and easy on valve springs). My guess is that the engine would peak the horsepower at about 5500 and a 500 rpm higher shift point would keep you in your 6000 rpm hard limit. Your valve spring pressures would be adequate.

[427dart]

My mistake..I was thinking BB Chevy!

[70GS455]

Ok, I've never been one to subscribe to the fact that there aren't certain specific nuances to different families that may/may not require a tweak to a cam spec. Someone here may specialize and have more experience in the Buick stuff and can lend more information. I have built a whopping zero Buick engines, so my specs are based on my experiences with other engine families.....mostly Fords.

Based on your desires, rpm requirements, the head flow, port volume, intake flow, exhaust flow, intake/exhaust flow ratios, displacement, vacuum requirements, etc., I'd be at:

293/301, 239/247 @ .050", .606"/.619" lift at 1.6RR, 114 LSA on a 106 ICL. It would have 69° of overlap, which should still operate your power brakes. Lobes are not aggressive (I have ran these lobes on some of my Clevelands with a 1.73RR and they are quiet and easy on valve springs). My guess is that the engine would peak the horsepower at about 5500 and a 500 rpm higher shift point would keep you in your 6000 rpm hard limit. Your valve spring pressures would be adequate.

Brent, thaks for your input. What manufacturer, lobe series, part no. etc are the above specs from? Thanks

[70GS455]

Do you know the intake port volume by chance?

260 cc

I misspoke earlier. They were measured at 190 cc