excess cylinder pressure/cam chioce

[mbandit]

My 440 Charger has been running but its not making real power.  To cut a long story short my engine builder put together a 9.7:1 CR with no quench and iron heads...We ended up with 210 psi cylinder pressures.

It was too expensive to go back to dome pistons/new heads so we put in thicker head gaskets which got us down to 9.1:1 at 185 psi with the cam advanced a little.  We now need to choose a cam that will bleed off another 20psi.  Help me choose a new cam.  Specs are:

Car will be used on street, 93 octane pump gas
3.55 gears, stall is about 2500 rpm
1 7/8 Hooker headers, Steet Dominator Manifold, 750 Holley
Bowl ported 906 heads, 80cc
28" diameter tires, 10" wide
Crane roller rockers, 1.6 ratio
Current cam is a Reed Torque Master hydraulic 276/282 - 223/228 @ 0.050, 110 LSA, valve lift is 0.502/0.512 @ 0.050 with the 1.6 rockers
(the cam/lifters and 3 bolt timing set will be up for sale soon if someone's interested, less than 200 miles, nothing wrong, Reed has a great reputation)

I think I need something like 236/242 @ 0.050 (tops) with 112 LSA and about the same lift.  I would prefer to be just on the high side so that we can retard it if necessary.   

Someone help me zero in.

Thanks,

Mel

[firefighter3931]

The new MP 284/484 on a 114* lsa would fit the bill. It has 238* dur @ .050 lift. There are programs available that will compute the static/dynamic compression based on cam timing events and the engine setup. This grind should bleed off enough low speed cylinder pressure to make it pump fuel friendly, inmo.

Ron

[mbandit]

Where do I find the sppecs on that cam?

LSA seems a bit wide, I prefer the rougher idle and I'm not worried about vacuum.

[firefighter3931]

Where do I find the sppecs on that cam?

LSA seems a bit wide, I prefer the rougher idle and I'm not worried about vacuum.

You can't have it both ways.A rough idle comes from a tight lsa with lots of overlap. Those types of grinds build lots of cylinder pressure. If you want to use a narrow lobed profile, you'll need a better engine combo....zero deck flattop, alum head and 10.5:1 static compression max with .040 quench. You're trying to "bandaid" a mismatched combo by covering up the problem with a cam choice. I don't see it happening unless you go really big on the cam (MP509) but then the car will be a dog. That stick needs 3500 stall and 4.10 gears.

Ron