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Correct Idle Speed for 5.7L 350 V8

I have an '86 GMC 1/2 ton pick-up that now has a 5.7L 350 V8 in it. The emissions control label on the front of the engine compartment is for the original engine (a 4.3L V6) and says I should set the fast idle speed to 2200 RPM and the idle speed to 500 RPM. Does anyone have an idea if these numbers are good to use for setting the idle speed on my V8 as well?

The truck has A/C, automatic transmission, I've got the spark plugs gapped to .045, and the ignition timing is set to 8. Rochester Quadrajet M4ME Carburetor (17085210).

Anyone know the proper idle speed specifications for this type of engine?

Thanks, austin

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austin
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Reply to
austin

Gap sounds right, idle speed hot in gear 600 rpm, 800-900 rpm cold in gear. What year engine, and is it all original ie correct distributor for the year of the engine?

Whitelightning

Reply to
Whitelightning

Thanks for the post, Whitelightning. It's an older engine (I would say roughtly the same year as the truck--mid-80s) that had a couple misses in it when I bought it. I had it rebuilt a year ago. The distributor matches and they work well together. Sorry I can't be more specific about the year. I've looked all over the engine for the VIN number (down by oil filter and along the engine case pad especially) and can't find it.

Austin

Whitelightn> > I have an '86 GMC 1/2 ton pick-up that now has a 5.7L 350 V8 in it.

Reply to
austin

Yeah, I should have mentioned about the original numbers: the emission control label says the fast idle 2200 RPM number should be set in Park or Neutral, and the 500 RPM idle speed set in Drive. The truck is due for a TX emissions inspection soon, so I might retard the timing some before I take it in. I think specifications say it should be set at 8 BTDC (4 on the timing indicator), right?

austin

aust> Thanks for the post, Whitelightning. It's an older engine (I would say

Reply to
austin

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