RHS LIGHTNING

800.345.4545
jegs.com

The RHS 23-degree cylinder heads come complete with high-quality Comp Cams components (valvesprings, retainers, and keepers). They unleashed 468 lb-ft of torque from the 383 small-block at 3,900 rpm and 422 horses at 5,500 rpm. This head incor-porated a larger 72cc cumbustion chamber, which produced lower compression on our test engine than the smaller 64cc chambers featured on many of the other heads.

CATEGORY 2
MODEL: Cast-Iron SB-Chevy Cylinder Heads, 200cc
PN: 12320-01
PRICE: $1000/pair
Weight: 51 pounds each
True measured combustion chamber volume: 72 cc
True measured intake and exhaust port volume: 200 cc; 75 cc
Spring pressure: 115 lbs. on seat; 275 lbs. at 0.0500-inch lift
installed height: 1.850 inch
Valve size: 2.06/1.60-inch
Intake flow at 0.400 lift: 209.5 cfm
Complete, assembled with guideplates
Airflow
Valve lift.050.100.200.300.400.500.600
Intake Corr test flow3065122170210233263
Exhaust Corr test flow224591128152167176
POWER
Average torque:432 lb-ft
Average horsepower: 381 hp
RPMlb-ftHP
3,200442269
3,300442278
3,400450291
3,500457304
3,600458314
3,700463326
3,800466337
3,900468347
4,000467356
4,100467364
4,200465372
4,300463379
4,400461386
4,500459393
4,600456399
4,700452404
4,800446408
4,900439410
5,000434413
5,100429416
5,200424420
5,300418422
5,400409421
5,500403422
5,600395421
5,700384416
5,800374413
5,900367413
6,000361412
6,100348404