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The OEM's went to rollers to be able to meet the EPA standards ( and a good portion of that was to cut friction losses ), not for performance reasons. Street grind flat tappet cams can easily duplicate roller performance with a lot less valve train stress - and BTW, those high load valve springs needed with rollers affect valve train longivity at ALL rpm's - all the time. That equates to not only higher initial valve train $, but higher $ throughout the entire life of the valve train( and only the valve train if you are lucky ). The point I have been trying to make here is not that rollers are a bad thing, but that they are mismarketed by many cam manufacturers ( for obvious reasons - $$$ ) and sold to the ( to be kind ) less knowledgeable as a major performance gain when in most street and mild performance appications they are not. JMO. My suggestion is that before you pop for a roller cam, take a good look at your particular application. Don't just jump in to a roller because " all performance engines gotta have one".




i dont mean to digress but HUH?
frictional losses at the lifter ? = emission output?
more like valve events..that allow for a longer burn cycle to take place before exhaust valves open sending incomplete combustion gases out the tail pipe. that constitutes emissions..
holding the valve closed longer in degrees of crankshaft rotation extends the burn cycle..then having an opening ramp rate faster so the valve opens to the same lift rate later in crank rotation..achieving the same or more optimal max open rates in relation to crankshaft degrees..is more likely...
or Intake valve events that prevent reversion and egr issues.

seems more likely the causation..

now if we where talking oem extending the oil changes to 10,ooo miles.because of rollers..you may have causation to justify that one...?


365" Iron J heads,,3480lbs best 1.39 60ft on SS springs.10.54,124 mph ...6.67 1/8th et.average 60fts 1.46 w/ small cam &.063 no2 pill tagged & insured
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