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Lazer Cam profile #1 Street/Track use. Good to 5500 rpm.
272` advertised duration 210`@0.050" with 0.418" valve lift on a 108 to 110` lobe separation. Good idle.
Lazer Cam profile #2 Short Track use. Good power from 2500 to 6000 rpm
275` advertised duration 222`@0.050" with 0.430" valve lift on a 106 to 108` lobe separation. Fair idle.
Lazer Cam profile #3 Sustained high RPM usage. Good power to 6500 rpm.
280` advertised duration 228`@0.050" with a 0.436" valve lift on a 106` lobe
separation. Rough idle.
Stock cam profile:
197`@0.050" duration with a 0.370" valve lift on a 114` lobe separation.
CHEVETTE 1.6 &1.9 OHC PROFILES STOCK BASE CIRCLE DIAMETER
duration
lobe valve
valve approximate
adv. .050 VL lift
lash lift
rpm range
267 210
.260 .000
.418
2000-5200
272 216
.265 .000
.426
2200-5600
278 222
.267 .000
.430
2500-6000
282 228
.271 .000
.435
3000-6500
290 236
.271 .000
.435
3500-7000
300 249
.283 .000
.455
4200-7700
308 256
.283 .000
.455
4600-8100
318 266
.283 .000
.455
5000-8500
set of rockers, # 1025-8
and springs, # 910-8
There 2 heads for Chevette: 1976-1980, and 1981-1987.
The 76-80 head has better intake ports, and will flow more air. The valve
spring seat is high, giving only 1.260" installed height. It must be
machined down .040" to get an installed height of 1.300" so you can use our
recommended #910 valve spring.
The 81-87 head has a swirl intake port which is very restrictive to air flow.
Consequently, it does not make power as well as the earlier head without
careful port work. It does, however, have a taller (1.300") valve spring
installed height in stock form. Our recommended #910 spring fits with no
machine work.
The # 910 spring fits a stock retainer.
The stock hydraulic adjusters have given us no trouble.
Chevettes work well in a basic 2500-6000 rpm range when properly built with
an appropriate camshaft. Operating them at a substantially higher rpm range
requires the kind of work that usually doesn't fit well with basic sportsman
racing; either due to rule structure or expense.
The camshafts we supply have stock diameter base circles on the lobes and
require stock valve train geometry. We do not make them to fall in on any
particular intake centerline-THEY MUST BE DEGREED IN - DEGREE WHEEL AND DIAL
INDICATOR REQUIRED. Use a light checking spring to avoid squishing the
hydraulic adjuster and getting incorrect readings. These cams have the same
1/4" pin as a Chevy V8, so you can use the same bushing kits.
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