Camshaft Comparison
11-25-2006, 02:00 PM
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Camshaft Comparison Similar camshaft comparison between:
#1: 238/240 112+2 --> 64 degrees of overlap
#2: 238/242 114+4 --> 61 degrees of overlap
What differences would there be when installed in 402cid engine, great flow through heads (71% 'exhaust/intake' ratio), M6.
Looking for info like: "area under the curve" differences, fuel economy, low rpm highway cruising. Which one would be more desireable, why?
#1: 238/240 112+2 --> 64 degrees of overlap
#2: 238/242 114+4 --> 61 degrees of overlap
What differences would there be when installed in 402cid engine, great flow through heads (71% 'exhaust/intake' ratio), M6.
Looking for info like: "area under the curve" differences, fuel economy, low rpm highway cruising. Which one would be more desireable, why?
11-25-2006, 03:31 PM
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Originally Posted by squealingtires
Similar camshaft comparison between:
#1: 238/240 112+2 --> 64 degrees of overlap
#2: 238/242 114+4 --> 61 degrees of overlap
What differences would there be when installed in 402cid engine, great flow through heads (71% 'exhaust/intake' ratio), M6.
Looking for info like: "area under the curve" differences, fuel economy, low rpm highway cruising. Which one would be more desireable, why?
#1: 238/240 112+2 --> 64 degrees of overlap
#2: 238/242 114+4 --> 61 degrees of overlap
What differences would there be when installed in 402cid engine, great flow through heads (71% 'exhaust/intake' ratio), M6.
Looking for info like: "area under the curve" differences, fuel economy, low rpm highway cruising. Which one would be more desireable, why?
238+242=480 480/4=120 120-114= 6 overlap
now the cam has built in advance and i don't know how much that changes things. most gurus do not like anything more than +2 built into the cam. good luck. maybe Predator or Patrick G. will help you.
Last edited by mullenh; 11-25-2006 at 05:15 PM. Reason: spelling
11-25-2006, 05:07 PM
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Originally Posted by squealingtires
Similar camshaft comparison between:
#1: 238/240 112+2 --> 64 degrees of overlap
#2: 238/242 114+4 --> 61 degrees of overlap
What differences would there be when installed in 402cid engine, great flow through heads (71% 'exhaust/intake' ratio), M6.
Looking for info like: "area under the curve" differences, fuel economy, low rpm highway cruising. Which one would be more desireable, why?
#1: 238/240 112+2 --> 64 degrees of overlap
#2: 238/242 114+4 --> 61 degrees of overlap
What differences would there be when installed in 402cid engine, great flow through heads (71% 'exhaust/intake' ratio), M6.
Looking for info like: "area under the curve" differences, fuel economy, low rpm highway cruising. Which one would be more desireable, why?
11-25-2006, 06:49 PM
#4
238/240 with 112 lsa = 15* overlap
238/242 with 114 lsa = 12* overlap
those are small cams for use in a 402 cid engine. i would opt for the 238/240 - 112 lsa because it would offer a better tq curve (more "under the curve" and it would come in sooner) and more potential for upper rpm power. both cams would provide excellent low rpm driving manners and when compared on a dyno, would be very similar.
if it was me, i'd be using a 25x/26x cam with a 108+2 lsa in that 402, but we obviously have different goals.
overlap calculator: ... [ indur+exdur / 2 = N. N - LSAx2 = overlap ]
238/242 with 114 lsa = 12* overlap
those are small cams for use in a 402 cid engine. i would opt for the 238/240 - 112 lsa because it would offer a better tq curve (more "under the curve" and it would come in sooner) and more potential for upper rpm power. both cams would provide excellent low rpm driving manners and when compared on a dyno, would be very similar.
if it was me, i'd be using a 25x/26x cam with a 108+2 lsa in that 402, but we obviously have different goals.
overlap calculator: ... [ indur+exdur / 2 = N. N - LSAx2 = overlap ]
11-25-2006, 10:45 PM
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Originally Posted by s346k
238/240 with 112 lsa = 15* overlap
238/242 with 114 lsa = 12* overlap
overlap calculator: ... [ indur+exdur / 2 = N. N - LSAx2 = overlap ]
238/242 with 114 lsa = 12* overlap
overlap calculator: ... [ indur+exdur / 2 = N. N - LSAx2 = overlap ]
[(287+289)/2]-112*2=64* -->good
[(287+291)/2]-114*2=61* -->good
I think either of these are gonna be great for a DD car. DCR is way up there at 8.882:1. However it is calculated the overlap difference is 3*, so would camshaft #2 have better off-idle torque? Would fuel consumption be noticable on 1 tank of gas between the two of these (highway miles @70mph)?
Originally Posted by s346k
those are small cams for use in a 402 cid engine.
