JUN 272

DSPORT Magazine technical showcase editorial on EVO 4G63 camshaft options

MANUFACTURER: JUN
ENGINE MODEL: 4G63 EVO 8
CAMSHAFT PN# (INTAKE): 1004M-M012
CAMSHAFT PN# (EXHAUST): 1004M-M142
SPEC CARD# : N/A

INTAKE EXHAUST
CAM TIMING EVENTS
Centerline 110° 110°
Valve Opening @ 1.0mm 7.3° ATDC 38.9° BBDC
Valve Opening @ 0.050″ 10.6° ATDC 35.6° BBDC
Valve Closing @ 1.0mm 39.4° ABDC 7.3° BTDC
Valve Closing @ 0.050″ 35.8° ABDC 10.9° BTDC
DURATION
Actual Duration @ 1.0mm 212.1° 211.6°
Actual Duration @ 0.050″ 205.1° 204.7°
Claimed Duration @ 1.0mm 214.0° 214.0°
PEAK LIFT
Peak Valve Lift 10.8mm (0.425″) 10.2mm (0.401″)
Peak Cam Lift 6.2mm (0.245″) 5.9mm (0.232″)

Manufacturer’s Pitch

When developing a high lift camshaft at JUN, the detailed data for each type of a car is taken, suitable valve springs and retainers are engineered and the optimal profile is determined. The advanced camshaft series, with very high lift, is designed for use only on high power engines. Reinforced valve springs are required.

JUN 272 camshafts vertical

INFO

Ahtough we could only get our hands on one of the JUN camshaft offerings for the 4G63 EVO 8, this camshaft set proved to deliver loads of power paired with the requisite lumpy idle. This pair of camshafts provided some of the highest VE numbers across our camshaft test group. Unlike most of the camshafts, the JUN 272s only began to deliver an increase in power production from 5,000 RPM up to 8,500 RPM. Our dyno runs recorded over 550 wheel horsepower from the JUN 272-equipped 4G63, a 23.5 percent increase in power over factory.


RUNDOWN

DSPORT Magazine technical showcase editorial on EVO 4G63 camshaft optionsDSPORT Magazine technical showcase editorial on EVO 4G63 camshaft options

557.56 WHP @ 8,500 RPM
404.96 LB-FT @ 6,200 RPM

Peak power checked in at 8,500 RPM, as the power curve flattened out from 7,000 to 8,500 RPM. Peak boost was reached at 4,600 RPM. The torque curve remained flat from 5,500 to 7,500 RPM and tapers off higher slightly in the power band. Maximum torque of nearly 405 lb-ft was reached at 6,000 RPM. VE values of 99.0 or higher were recorded from 5,000 to 7,000 RPM. Superior VE figures superior to the factory camshafts were recorded from 4,000 to 8,500 RPM.

HORSEPOWER

RPM/WHP FACTORY JUN 272 GAIN/(LOSS)
2500 49.66 47.64 (2.02)
3000 82.45 62.22 (20.23)
3500 112.31 91.03 (21.28)
4000 166.27 128.85 (37.42)
4500 281.42 255.26 (26.16)
5000 323.28 351.58 28.30
5500 371.95 414.73 42.78
6000 399.03 457.29 58.26
6500 415.72 481.20 65.48
7000 451.50 513.16 61.66
7500 N/A 539.58 N/A
8000 N/A 546.77 N/A
8500 N/A 557.56 N/A

VOLUMETRIC EFFICIENCY

RPM/% FACTORY VE JUN 272
2500 80.5 88.7
3000 88.2 92.9
3500 98.6 96.7
4000 85.9 96.6
4500 85.0 98.5
5000 89.1 100.0
5500 92.1 99.0
6000 88.7 101.5
6500 88.8 101.0
7000 84.9 99.0
7500 N/A 93.2
8000 N/A 88.9
8500 N/A 82.3