Cams are not a black & white issue. Hot Rod's Camshaft book is very enlightening on the subject & there is plenty of surprises. For one, it dispels the myth about tight LSA's being peaky. A couple of tests were done using identical cams, except for LSA. One pair was compared using 108 & 112 LSA. Another test also done using 110 & 114 LSA cams on 350 Chebby's [ what else!! ]. The results? " From the text: With the 108 deg cam, the engine produced 16f/p more torque & 5 more peak hp. But that only tells part of the story. From 2000 to 2750 rpm the 108 deg cam produced AT LEAST 30 f/p more torque at every data point; from 3000 to 4000 rpm, the average was 13 & 16 f/p." The test with the 110 & 114 LSA cams was similar; the 110 cam delivered more mid-range hp; the 114 cam delivered more top end hp, but the hp crossover point was not UNTIL 5250 rpm.
In another test in the book, three identical Isky cams, except for LSA, were tested. duration was 262/266 @ 050, solid lifter cams. The LSA's were 106, 108 & 110. The results? from the text: " The 106 LDA produced the most peak & average torque, as well as the most average hp & the highest cranking compression."
For the 106,108, 110 cams these are some of the numbers:
Peak tq: 504, 489, 479
peak hp: 580, 578, 583
Av thru 7000 rpm: hp: 525, 514, 506
tq: 476,463,452
There was also a test on advancing & retarding a cam 4 degrees. The cam was a Crane, 222/230 @ 050, 110 LSA.
It was tested straight up [0], 4 deg adv & 4 ret.
These are the results: 4 adv, 0, 4 ret:
Av tq thru 4000: 379.4, 373.2, 369.0
Av 4200 plus: 369.4, 371.4, 371.4
Av overall: 374.4, 373.2, 369.0. test rpm range was from 2000 to 6,250 rpm.
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