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How does this camshaft compare to that used in 427 L36. Any ideas on how it would compare to the L36 camshaft used in 68? My impression of the L36 is a very nice all around camshaft. Just wondering how it would compare to this 6272989? Thanks, Terry
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Re: Camshaft 6272989? LS5? How does this ....
All I have on the 989 cam are the gross timing numbers listed in the Chev. Power Manual, which aren't that much "bigger" than the L-36 cam, (The 989 is listed as "high-perf. street and marine"), but my suspicion is that it has more .050" duration and overlap than the '67 L-36 cam that was also used in 454s up to '72. Maybe Clem has the .050" data on the 989.
If you're happy with the current idle charactersitics and low end torque, I recommend you stick with the OE cam.
As with any OE engine, head massaging is the single best performance improvement you can make. It will increase top end power and useable revs by up to ten percent with essentially no impact on idle characteristics or low end torque.
Coincidently, I've done some preliminary system engineering investigation of the LS-5. It's "preliminary" because I am using head flow data from the Engine Analyzer library, and don't know how representative this data is for the OE heads in both factory machined and massaged configurations. I can't hang my hat on any performance predictions unless I have actual flow data for the specific head.
The L-36 cam has somewhat "advanced" POMLs of 110/120, and especially on a 454 with massaged heads, retarding it about 5 degrees with a CR of about 10:1 should yield a significant increase in power with a useable power bandwidth to 5500 and only a slight loss of low end torque while retaining the OE idle characteristics.
It also responds nicely to swapping the lobes with indexing of 120/120 and along with a 10:1 CR and massaged heads makes more torque/power from off idle to peak revs than the OE configuration, which only has 8.5:1 CR (and only needs regular unleaded) and is rated at 270 net HP.
It think the LS-5 has a lot of potential for increased performance across the range without altering the OE idle characteristics or visual appearance and without using a bunch of hot rod parts.
Duke -
Re: Camshaft 6272989? LS5? How does this ....
I will keep this information and use it to build my engine. I found that camshaft (989) and was wondering if it was somehow the same camshaft. I will stick with the original camshaft and I think I will consider retarding the cam to produce the upper bandwidth of power.
The person that has the 989 camshaft states it will pull hard to 6500 rpm?? A little more top than I want plus I know I will probably be lucky to get 5500 rpm with very nice valve train.
Just a little tid bit of information. I was reading something on I believe either Crane's or ProComp's full roller rockers for street use and they did advertise the weight over the valve stem as less than conventional rockers?? I thought that was interesting and sort of nice. I had asked the people on the help lines and the people that I talked to had no clue as to what I was asking??
Thanks, TerryComment
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Re: Camshaft 6272989? LS5? How does this ....
it is a hyd lifter marine engine cam. specs .500 IN/.500 EX lift,duration intake 222@.050/exhaust 221@ .050 exhaust. same as 14096209 i have been toldComment
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Thanks! Terry *NM*
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