Author Topic: Camshaft Selection for your New Engine  (Read 6122 times)

Offline 73ss

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Re: Camshaft Selection for your New Engine
« Reply #15 on: December 19, 2019, 03:02:50 PM »
I'm finding most everything is ground on a 110LSA, with the exception of computer friendly cams which are 114. Since this was originally a EFI engine (98 suburban) I'm assuming this is done to produce enough vacuum to keep the map sensor happy.

Offline Cliff Ruggles

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Re: Camshaft Selection for your New Engine
« Reply #16 on: December 21, 2019, 01:24:15 AM »
There should be a clue in there someplace as to why a 114 LSA cam is computer friendly and 110 LSA is not.

The tighter LSA increases overlap and make it much harder to get clean exhaust to be computer and emission friendly. 

Of course it's a little more complicated than that as there are many other factors that effect the end results, but for the most part tight LSA puts more unburned particles in the exhaust stream and makes it harder to get the engine thru emission testing or to be computer friendly plus it lowers the vacuum production at idle all else being equal........Cliff

Offline Cliff Ruggles

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Re: Camshaft Selection for your New Engine
« Reply #17 on: April 08, 2020, 03:55:16 AM »
Bump...