Idle RPM's for 300 I-6

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wildcard
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Idle RPM's for 300 I-6

Post by wildcard »

I have a 300 I-6, 3 speed manual with electronic ignition.
I'm trying to get it running better so I would like to go back and get everything set back close to specs and adjust from there.
I have the timing at 10°.
What would be the ideal idle RPM's on this?
Once I get this, then I can start tweaking the timing and carb.
Thanks
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1972hiboy
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Re: Idle RPM's for 300 I-6

Post by 1972hiboy »

I would think in the 650-750 rpm neighborhood. :hmm:
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Re: Idle RPM's for 300 I-6

Post by eggman918 »

550 RPM for 1972 and earlier
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wildcard
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Re: Idle RPM's for 300 I-6

Post by wildcard »

Ok. Thanks.
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Re: Idle RPM's for 300 I-6

Post by WarEagle »

wildcard wrote:I have a 300 I-6, 3 speed manual with electronic ignition.
I'm trying to get it running better so I would like to go back and get everything set back close to specs and adjust from there.
I have the timing at 10°.
What would be the ideal idle RPM's on this?
Once I get this, then I can start tweaking the timing and carb.
Thanks
Is it a stock motor?
1972 F100 300 cid straight 6
2009 F150 4.6L Super Crew
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wildcard
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Re: Idle RPM's for 300 I-6

Post by wildcard »

Everything is stock except the electronic ignition.
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Re: Idle RPM's for 300 I-6

Post by Manny »

650-750 is where i would set it. With the 3 speed you have a little lee way.. :thup:
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Re: Idle RPM's for 300 I-6

Post by WarEagle »

I'm at 680-700 rpm in park, 560-580 in drive w/o choke. I have a mild grind cam built for torque. power band is something like 800 rpm to 3000 rpm.
1972 F100 300 cid straight 6
2009 F150 4.6L Super Crew
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Re: Idle RPM's for 300 I-6

Post by jzjames »

My OLD 300 I6 is at 550.

Gives me a sense of how tuned up we are. 8)
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Re: Idle RPM's for 300 I-6

Post by wildcard »

I haven't gotten far with mine. I got out and changed the rubber parts of my fuel line. I had to wire up a lever of some sort that's between my carb and choke to keep it from dropping too far when the choke releases. That was a week ago. Since then, it's either been too cold or my arthritis has been too bad. I sure hate cold weather.
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Re: Idle RPM's for 300 I-6

Post by Manny »

wildcard wrote: I sure hate cold weather.

No doubt..... :doh:
Just another Ford fool named Dan.
The Junk that hangs around
67' F-250 highboy Camper special cross breed currently under way
http://www.fordification.com/forum/view ... 22&t=86706
1974 Bronco 302 3 speed
1984 bronco 302 c6 35's
1994 F350 7.3 5spd dually.
woods wrote: The rust holes in my truck were a factory install (very rare).
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Re: Idle RPM's for 300 I-6

Post by wildcard »

OK, I got the RPM's set at 700.
I'm gonna start a new post on my carb.
Thanks for everyone's help and comments.
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