Cam Suggestions for a 540
10-08-2015 | 08:33 PM
#31
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Joined: Jul 2004
Posts: 11,332
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From: chicago
Comp and Crane stuff are older lobes.Up until recently we didn't have hydraulic lifters that would support the higher lift cams. Now we do. About a year and a half ago I called everyone and there brother trying to find .700 + lift hydraulic lobe profiles. The only ones that had them were Bullet and Cam Motion. I highly doubt the larger companies are going to get into more exotic hydraulic cams for BBC I really don't think there is a big market for it. From what I've been told the LS market is really starting to pick up. And when you only need 1 cam core on the shelf to make whatever cam you want (instead of a gazillion) it's a no brainer (business wise) what to focus on.
I think you dont see big lobe hydraulics much even today, because most guys wanting big lift, dont want a hydraulic, based on experience that they really dont hold up well in an endurance application, even with modern lifters. Kind of like why nobody is making 4 5/8 nodular cranks.
Whos running +700 lift hydraulic roller cams successfully in the marine offshore stuff, even with modern lifters ? Not talking about a dyno pull, or race engine, talking poker run or pleasure engines ? I hoestly dont know. I know of a few who tried it, even with the high end morels , and ended up going back to solids , in bigger power applications.
Last edited by MILD THUNDER; 10-08-2015 at 08:42 PM.
10-08-2015 | 08:42 PM
#33
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Joined: Nov 2004
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From: On A Dirt Floor
Here's a look at comp's master lobe profiles they grind from. Page 16 is their marine grinds. They aren't offering anything in .650 lift with a 1.7 rocker, until the duration gets up to 254 range. In the 240* range, their "High lift" profile, is a .360 lobe/.612 valve lift. Seems like them and crane, are generally on the same page with lobe sizes for basic bbc marine/endurance stuff. Maybe the independent cam guys know some things they don't about duration vs lobe size, spring life, and so on. Possibly having in house spintrons, and grinding machines, might be a benefit to designing cams for all different applications, I would assume.
http://www.compcams.com/Technical/Ca...obeCatalog.pdf
http://www.compcams.com/Technical/Ca...obeCatalog.pdf
So.....if you call one of 2 'higher up' people in Comp Cams, you will more likely get another recomendation than the rest of the phone help and what is recomended in the catalog.
10-08-2015 | 08:46 PM
#35
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Joined: Oct 2015
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From: Calgary, AB
They are for sale but they are not out of the heads so I am not pushing to sell them. Yes I am replacing them with inconel valves but waiting to see what happens with the USD CAD exchange rate.
10-08-2015 | 08:46 PM
#36
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Joined: Oct 2005
Posts: 11,691
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From: Olmsted Falls,Ohio Marblehead,Oh
not sure that's why I ask, the performance of my old engines and new ones are very different, I have less cubes with better heads and cams (I was told) vs a little more cubes and lots smaller cams and pro comp heads, boat still never beat last engines speeds... I mean my old cams only had .578 lift.....on 565CI
10-08-2015 | 08:55 PM
#37
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Joined: Apr 2005
Posts: 2,150
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From: Northport N.Y.
Just asking how many people had a quality stainless exhaust valve fail? He does only have a 22' boat. I had severe duty stainless valves in my twin turbo small block with no issues at 1800-1900 exhaust temp. Around 1000hp.
10-08-2015 | 08:57 PM
#38
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Joined: Oct 2005
Posts: 11,691
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From: Olmsted Falls,Ohio Marblehead,Oh
I have ..... twice.....only have a pic of one saved... here is second time after I didn't learn from first failure...
[ATTACH=CONFIG]546312[/ATTACH]
[ATTACH=CONFIG]546312[/ATTACH]
