67-70 combo

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Combo 67.

Combo 67 uses the basic Brodix heads and Victor Jr. intake. This combination makes 401 HP and 456 ft-lbs of torque. Compared to the previous combo, these heads make 8 more HP and 21 more ft-lbs of torque with the same Victor Jr. intake. Compared to Combo 64, with the same heads and RPM intake, this combination produced 4 more HP and 11 less ft-lbs of torque.

 

Displacement:

408 cu. in., (0.040 in. over 400)

Carburetor:

Holley 750 double pumper with a 2 in. Edelbrock spacer

Heads:

Brodix street heads, with 165 cc intake runners and 2.02/1.60 in. valves

Intake:

Edelbrock Victor Jr.

Camshaft:

Lunati Street Master hydraulic, with 285° of duration, 235° of duration @ 0.050 in. lift, and 0.507 in. of lift

Rockers:

Lunati

Headers:

Hedman 1 3/4 in. headers

Pistons:

Lunati forged

Rods:

Lunati

Crank:

Lunati

Distributor:

MSD 6A

Comp. Ratio:

10.2:1

MAX HP:

401 @ 5000

MAX Torque:

455 @ 4000

Combo 68.

Combo 68 is the last of the 408 cu. in. combinations. The Victor Jr. intake is combined with the -8 heads to make 417 HP and 460 ft-lbs. This is 16 more HP and 5 more ft-lbs of torque than the other Brodix heads with the Victor Jr. intake. This combination produces 7 more HP and 16 less ft-lbs than the combo with the same heads and the RPM intake. Again, the Performer line proves to be more of a streetable intake than the race-oriented Victor Jr.

 

Displacement:

408 cu. in., (0.040 in. over 400)

Carburetor:

Holley 750 double pumper with a 2 in. Edelbrock spacer

Heads:

Brodix -8 heads, with 185 cc intake runners, 2.05/1.60 in. valves, and a back-cut on the exhaust valve

Intake:

Edelbrock Victor Jr.

Camshaft:

Lunati Street Master hydraulic, with 285° of duration, 235° of duration @ 0.050 in. lift, and 0.507 in. of lift

Rockers:

Lunati

Headers:

Hedman 1 3/4 in. headers

Pistons:

Lunati forged

Rods:

Lunati

Crank:

Lunati

Distributor:

MSD 6A

Comp. Ratio:

10.2:1

MAX HP:

417 @ 5000

MAX Torque:

460 @ 4500

Combo 69.

Combo 69 comes from a 1996 reprint of a Holley article in Chevy High Performance.

Holley components are used to produce an engine that makes 400 HP and 400 ft-lbs of torque. 110 octane gasoline is used on this engine, and I almost decided to omit it from the combos. I would assume that the higher octane will raise power at least 10 HP, but I am unsure of the exact increase. Anyhow, maybe this combination is still helpful.

 

Displacement:

355 cu. in.

Carburetor:

Holley 750 vacuum secondary (110 octane gas is used, so the HP and torque numbers will be a good bit higher than with ordinary 93 octane.)

Heads:

Holley Systemax, with 2.02/1.60 in. valves, a 20° valve angle, and 185 cc intake runners

Intake:

Holley dual plane

Camshaft:

Holley, with 234/242° of duration @ 0.050 in. of lift, and 0.473/0.488 in. of lift

Rockers:

Crane Energizer aluminum 1.5:1

Headers:

1 5/8 in. Flowtech

Pistons:

TRW forged

Rods:

stock

Crank:

cast

Distributor:

Performance Distributors HEI

Comp. Ratio:

9.2:1

MAX HP:

405 @ 5600

MAX Torque:

408 @ 4600

Combo 70.

Combo 70 comes from pages 29-31 the 2000 edition of Petersen's Hot Rod Camaros.

This engine is a 406 cu. in. version that is to be put in Mark Stielow's "Thrasher" 1969 Camaro. The build uses some impressive parts such as a roller cam, a Cola crank, and CNC'd Edelbrock Victor Jr. aluminum heads. The roller cam is pretty stout, and the lift seems huge with the 1.6:1 rockers; however, the EFI helps this engine to still be streetable. Note that the HP peak is at 6000 rpm, while the torque peak is at a low 4000 and 4100 rpm. This torque peak is only at 67-68% of the peak power rpm. Most engines have peaks that are closer, with the torque peak occuring at 75-80% of the HP peak rpm. Perhaps the EFI is the reason for this.

 

Displacement:

406 cu. in.

Induction:

Accel EFI

Heads:

Edelbrock Victor Jr. CNC

Camshaft:

Crane hydraulic roller, with 286/294° of duration, 236/244° of duration @ 0.050 in. of lift, and 0.525/0.579 in. of lift (Corrected valve lift with 1.6:1 rockers is 0.560/0.579 in.)

Rockers:

Crane 1.6:1

Headers:

Hedman 1 5/8 in.

Pistons:

Wiseco forged aluminum

Rods:

Trick Flow 6 in.

Crank:

Cola

Distributor:

Accel

Comp. Ratio:

?

MAX HP:

460 @ 6000

MAX Torque:

450 @ 4000 and 4100

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