cam gear oiling
#13
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Joined: Jan 2006
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From: taxachusetts
I've done a groove to add oil,noticed nothing better in terms of wear compared to the non grooved ones.on msd distr's,I use only the top o-ring.of course the spring seat pressures were never over 225lbs on the solid rollers.and nver saw anything on hydraulics.
#14
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Joined: Jul 2004
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From: chicago
Some good info on this mod here. I see some guys have cut a groove in the block to get some addtl oiling to the cam gear.
Makes sense, like guys grooving lifter bores, or lifters, with flat tappet lifters.
http://garage.grumpysperformance.com...ear-wear.1701/
Makes sense, like guys grooving lifter bores, or lifters, with flat tappet lifters.
http://garage.grumpysperformance.com...ear-wear.1701/
#15
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Joined: Feb 2012
Posts: 4,031
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From: westville, NJ
Has nothing to do with valve spring pressures. Roller cams are harder than flat tappet cams and they will eat a standard iron gear. Apparently the GM perf cams like the 454HO and ZZ502 are billet stock and require special dist. gears. I am not sure about the standard production roller cams. I just picked up a 454HO cam for one of my builds and am wondering if all production engines from the roller era come with the hardened dist gear. Where do i find details on the distrib mod for gear oiling?
#16
#17
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From: chicago
Found this on cranes site
Chevy V-8's, small block, big block, and 90? V-6 engines, all use splash lubrication to oil the distributor gear. Although higher RPM operation provides sufficient lubrication to prevent wear, low speed use can be a problem. The situation can become critical if a high volume oil pump is used. The high volume oil pump was developed for engines where bearing clearances were increased over stock. These work fine in racing engine applications, where extra clearance is provided in the short-block.
However, when a high volume oil pump is used in an engine with stock internal clearances, the increased volume of oil can't flow through the engine fast enough to relieve the back pressure created. This places an increased load on the distributor gear, and leads to accelerated wear.
Once the gear on either an 8620 steel cam or a cast iron cam is worn excessively, the cam itself must be scrapped! There is no repair for this problem, and the only option is to buy a new cam. To eliminate this annoying and expensive problem, we offer a simple, do-it-yourself way to help oil the distributor gear and reduce this accelerated wear in Chevy V-8 and 90? V-6 engines.
On these engines, the lower portion of the distributor housing drops through the oil gallery that supplies oil to the lifters on the passenger side of the engine. Two rings at the bottom of the distributor housing seal the top and bottom of this galley. Oil flows around the distributor, between the two rings.
Solving distributor gear wear is as simple as filing or machining a .030" groove in the bottom ring of the distributor housing. A three cornered file can also be used.
The distributor housing should be grooved in any engine operated for extended periods at low engine RPM. With the distributor installed in the engine - ready to run - the groove should face TOWARDS THE CAMSHAFT. This will provide a reasonable flow of oil to lubricate and cool the distributor gear and cam gear as they operate.
http://www.cranecams.com/bulletins_listview.php?s_id=27
Chevy V-8's, small block, big block, and 90? V-6 engines, all use splash lubrication to oil the distributor gear. Although higher RPM operation provides sufficient lubrication to prevent wear, low speed use can be a problem. The situation can become critical if a high volume oil pump is used. The high volume oil pump was developed for engines where bearing clearances were increased over stock. These work fine in racing engine applications, where extra clearance is provided in the short-block.
However, when a high volume oil pump is used in an engine with stock internal clearances, the increased volume of oil can't flow through the engine fast enough to relieve the back pressure created. This places an increased load on the distributor gear, and leads to accelerated wear.
Once the gear on either an 8620 steel cam or a cast iron cam is worn excessively, the cam itself must be scrapped! There is no repair for this problem, and the only option is to buy a new cam. To eliminate this annoying and expensive problem, we offer a simple, do-it-yourself way to help oil the distributor gear and reduce this accelerated wear in Chevy V-8 and 90? V-6 engines.
On these engines, the lower portion of the distributor housing drops through the oil gallery that supplies oil to the lifters on the passenger side of the engine. Two rings at the bottom of the distributor housing seal the top and bottom of this galley. Oil flows around the distributor, between the two rings.
Solving distributor gear wear is as simple as filing or machining a .030" groove in the bottom ring of the distributor housing. A three cornered file can also be used.
The distributor housing should be grooved in any engine operated for extended periods at low engine RPM. With the distributor installed in the engine - ready to run - the groove should face TOWARDS THE CAMSHAFT. This will provide a reasonable flow of oil to lubricate and cool the distributor gear and cam gear as they operate.
http://www.cranecams.com/bulletins_listview.php?s_id=27




