Posted By: Scott58
493 Buildup Miscellaneous Questions - 03/31/09 08:37 PM
I'm getting ready to build a 493 for my 70 RR coupe. The car currently has a TRW based 440 with ported 915's, TM-7, 1" spacer, HP950, MP590 solid w/1.5 rockers, and 2" Super Comps into 3" exhaust (Old School!). 727 / 3.91 8 3/4 3800# with driver. On 275/50/15 Drag T/A's we ran a traction limited 11.95 at 117.5 last fall in cool air at 600' altitude. The car was driven 80 miles to the track (Muncie, IN) and run as driven. Chassis dyno says 392 HP at wheels, I'd guess 520 at the crank.
We are upgrading to new Moser axles and will be going to a 28" tall tire. I also have a new A&A 727 and 9 1/2" Dynamic converter (3800 stall) that we are installing now.
For the 493, I have a set of "stealth" heads, CNC ported by Jeff at MCH, and a port matched Street Dominator intake (to get some hood clearance). I'd like to re-use my headers and carb on the 493. Springs on the heads are the 440 source outers with some Comp 974 inner springs, 10 degree steel retainers and lash caps. 150# on the seat, 420# at .650", bind at .720". Heads milled to 82.5cc.
Flow Numbers:
Intake Exhaust Exhaust w/tube
.100 75.0 71.0 72.9
.200 156.7 120.4 124.8
.300 218.8 158.6 166.4
.400 264.2 184.7 198.1
.500 296.8 200.3 219.3
.550 308.2 206.2 228.6
.600 315.9 210.9 233.3
.650 320.7 215.8 238.2
.700 322.7 218.9 243.8
.750 325.6 220.8 248.2
I'm thinking zero to .005" deck height for quench with the closed chamber heads and standard gasket thickness ( .039"), static CR between 11.25 and 11.5, .030 over 440 stock block with 4.15 crank and 6.76 rods. solid flat tappet cam with about 290 duration, .650 lift ( with 1.6 rockers).
Use is 50% street / 50% strip, with trips up to 150 miles at a time. The current combo is fine for me as far as drivability, even with the .590 cam.
Objective is 80-100 HP more than current combo with equivalent drivability and good reliability.
Please offer your comments on the following:
RAS 1.6 rockers
1) Not too heavy for the RPM ( < 6800RPM) range for this engine?
2) Pros/cons to selecting the type of adjuster end ( ball versus cup)?
Camshaft
1) Comp MM solid 6587 lobe:
Dur @ .050” @ .200” Lobe 1.5 1.6
289 263 181 .404 .606 .646
2) Your recommendation on a cam
3) Need for lifter face oiling ( EDM hole) for these types of cams
Overall Buildup
1) Main studs?
2) Steel Caps?
3) 1/2" pickup?
4) oil passage mods?
Anything else you would like to mention!
We are upgrading to new Moser axles and will be going to a 28" tall tire. I also have a new A&A 727 and 9 1/2" Dynamic converter (3800 stall) that we are installing now.
For the 493, I have a set of "stealth" heads, CNC ported by Jeff at MCH, and a port matched Street Dominator intake (to get some hood clearance). I'd like to re-use my headers and carb on the 493. Springs on the heads are the 440 source outers with some Comp 974 inner springs, 10 degree steel retainers and lash caps. 150# on the seat, 420# at .650", bind at .720". Heads milled to 82.5cc.
Flow Numbers:
Intake Exhaust Exhaust w/tube
.100 75.0 71.0 72.9
.200 156.7 120.4 124.8
.300 218.8 158.6 166.4
.400 264.2 184.7 198.1
.500 296.8 200.3 219.3
.550 308.2 206.2 228.6
.600 315.9 210.9 233.3
.650 320.7 215.8 238.2
.700 322.7 218.9 243.8
.750 325.6 220.8 248.2
I'm thinking zero to .005" deck height for quench with the closed chamber heads and standard gasket thickness ( .039"), static CR between 11.25 and 11.5, .030 over 440 stock block with 4.15 crank and 6.76 rods. solid flat tappet cam with about 290 duration, .650 lift ( with 1.6 rockers).
Use is 50% street / 50% strip, with trips up to 150 miles at a time. The current combo is fine for me as far as drivability, even with the .590 cam.
Objective is 80-100 HP more than current combo with equivalent drivability and good reliability.
Please offer your comments on the following:
RAS 1.6 rockers
1) Not too heavy for the RPM ( < 6800RPM) range for this engine?
2) Pros/cons to selecting the type of adjuster end ( ball versus cup)?
Camshaft
1) Comp MM solid 6587 lobe:
Dur @ .050” @ .200” Lobe 1.5 1.6
289 263 181 .404 .606 .646
2) Your recommendation on a cam
3) Need for lifter face oiling ( EDM hole) for these types of cams
Overall Buildup
1) Main studs?
2) Steel Caps?
3) 1/2" pickup?
4) oil passage mods?
Anything else you would like to mention!