Author Topic: Best idle speed for "performance" not Emissions  (Read 3774 times)

Offline D.M.

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Best idle speed for "performance" not Emissions
« on: May 30, 2018, 08:23:21 AM »
Hi, I just had my Quadrajet(7028240) rebuilt for my 1968 Buick Wildcat. I'm at the 'Dialing" in stage after re-installing it and was wondering what the best idle rpm in drive would be for best stock performance. The manual states 550 rpm when in drive for best emissions. My engine has mild upgrades like stock big port heads, upgraded ignition, 3" x-pipe  with dual 2.5" exhaust for better flow. Stock transmission. ignition advanced to about 34* of mechanical timing. Any suggestions?

Offline Cliff Ruggles

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Re: Best idle speed for "performance" not Emissions
« Reply #1 on: May 31, 2018, 01:53:38 AM »
Stock cam or aftermarket?

If the converter is still stock you'll need to keep the idle speed low as it will hit pretty hard when placed in gear......Cliff

Offline D.M.

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Re: Best idle speed for "performance" not Emissions
« Reply #2 on: June 01, 2018, 07:57:38 AM »
Thanks for replying Cliff, Its a stock cam and converter. Should I just go with whatever idle RPM(In Drive) that gives max vacuum?...or whatever clunks into drive the least? I was just wondering if there is an advantage to have your car idle a little higher for a better gas pedal response.
Thanks.

Offline 77cruiser

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Re: Best idle speed for "performance" not Emissions
« Reply #3 on: June 01, 2018, 10:03:21 AM »
Just go for the stock settings with what you have.
Jim