Custom grind cam question...
05-20-2017, 05:55 PM
#1
Melting Slicks
Thread Starter
Custom grind cam question...
Posted a few threads about a 383 stroker short block I have on an engine stand......When I purchased it a few years ago the previous owner explained to me that it had a custom grind cam in it....Hydraulic flat tappet..
What exactly is a custom grind cam? I have an idea but I'm not exactly sure....I figured I would ask the members on the forum..
Thanks....
What exactly is a custom grind cam? I have an idea but I'm not exactly sure....I figured I would ask the members on the forum..
Thanks....
05-20-2017, 06:08 PM
#2
Race Director
The cam companies have a collection of lobe profiles. The lobes themselves are not what's custom.
A custom ground cam lets you take an intake and exhaust lobe that normally don't come on a specific cam, and you can specify the lobe separation (within reason limited by the cam blanks).
A common custom grind would be to specify a tighter lobe separation than the off-the-shelf version. Tighter separation builds more low and mid range torque, and in the right motor can even make more top end power.
A custom ground cam lets you take an intake and exhaust lobe that normally don't come on a specific cam, and you can specify the lobe separation (within reason limited by the cam blanks).
A common custom grind would be to specify a tighter lobe separation than the off-the-shelf version. Tighter separation builds more low and mid range torque, and in the right motor can even make more top end power.
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zrc3john (05-20-2017)
05-20-2017, 06:44 PM
#3
Melting Slicks
Any chance you know who ground that cam, and can get in touch with them to find out what the specs are? I had Cam Motion grind me a custom BBC solid roller Cam with a billet core with a cast gear on the end because i was running nitrous. They ground it on a 114 CL with .691/.684 lift and a .262/.272 Dur @.050. Most off the shelf grinds will work with most engines, a custom grind has a purpose.
05-21-2017, 05:50 AM
#4
With so many cams available for the SBC there is really little reason for the expense of a custom ground unless there is something really unique about the engine.
In your context they probably meant they had an aftermarket cam vs a stock replacement cam.
In your context they probably meant they had an aftermarket cam vs a stock replacement cam.
05-22-2017, 09:10 AM
#5
Le Mans Master
Not sure I 100 percent agree with that. The builder may want the engine to perform a certain way in a given circumstance . By changing the specs they can tailor a cam that may be close but not exactly what he or the customer may be looking for.
contacting the builder or cam grinder would possibly yield some light. I can't see it being negative, it's likely that there could have been heads or compression that wasn't ideal for an off the shelf cam..
contacting the builder or cam grinder would possibly yield some light. I can't see it being negative, it's likely that there could have been heads or compression that wasn't ideal for an off the shelf cam..
05-22-2017, 10:04 AM
#6
Melting Slicks
Thread Starter
Not sure I 100 percent agree with that. The builder may want the engine to perform a certain way in a given circumstance . By changing the specs they can tailor a cam that may be close but not exactly what he or the customer may be looking for.
contacting the builder or cam grinder would possibly yield some light. I can't see it being negative, it's likely that there could have been heads or compression that wasn't ideal for an off the shelf cam..
contacting the builder or cam grinder would possibly yield some light. I can't see it being negative, it's likely that there could have been heads or compression that wasn't ideal for an off the shelf cam..
05-22-2017, 11:10 AM
#8
Melting Slicks
The cam needs to be matched to the cylinder head and RPM goals of the engine. Lots of thought goes into picking the correct can for the correct application.