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idle speed
- Thread starter AUSMHLY
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Hi Roger,
I think the idlespeed is mostly personal preference. Factory specs usually call for about 500 rpm.
My personal preference is an rpm that is high enough that the engine won't stall at any temperature encountered. The idle speed tends to get a bit slower under very hot stop & go traffic conditions. Other considerations with the original generator is that the idle be high enough to prevent battery discharge during prolonged idle conditions. Also, the cooling system usually works better at a somewhat faster idle. I think a lot of folks try for something like 800 rpm.
The faster idle also brings in some of the distributor's centrifugal advance which tends to promote less combustion heat rejection to the engines cooling system.
I don't know about your car, but my BN2 is set up so that the first part of choke knob travel only affects the idle speed, doesn't really apply any choke, just fast idle. This allows convenient temporary resetting idle speed to anything needed for the conditions, ie. very hot driving conditions, altitude changes, fuel quality, etc.
D
I think the idlespeed is mostly personal preference. Factory specs usually call for about 500 rpm.
My personal preference is an rpm that is high enough that the engine won't stall at any temperature encountered. The idle speed tends to get a bit slower under very hot stop & go traffic conditions. Other considerations with the original generator is that the idle be high enough to prevent battery discharge during prolonged idle conditions. Also, the cooling system usually works better at a somewhat faster idle. I think a lot of folks try for something like 800 rpm.
The faster idle also brings in some of the distributor's centrifugal advance which tends to promote less combustion heat rejection to the engines cooling system.
I don't know about your car, but my BN2 is set up so that the first part of choke knob travel only affects the idle speed, doesn't really apply any choke, just fast idle. This allows convenient temporary resetting idle speed to anything needed for the conditions, ie. very hot driving conditions, altitude changes, fuel quality, etc.
D
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It appears that you may not care about long winded explanations about what or why. If so, just set it at 900 & be done with it. Sorry to clutter up the board.
D
D
Keoke
Great Pumpkin
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Yeah Dave, I thought that might be mistooken and I was just about to fisit. But on the BJ8 if the chokes are set up properly the first 1/4" or so will vary idle speed without applying any choke. Sorry it didn't just pull your leg a bit.---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
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The fast idle is a linkage operated cam. The more the choke is pulled, the faster the idle. I would set the fast idle to about 1,500 rpm when the choke is fully pulled.MarkA said:
If you set it up correctly, when the choke knob is pulled, the first part of the travel will increase idle speed without actually applying any choke. You can watch the carb linkage as you pull the choke to see the action. The shop manuals give pretty complete details on setting.
D
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900ish is perfect and that's if you can believe the tach. Not all car engines idle the same at the same tach speed so set the speed to whatever feels good.Dave Russell said: