What RPM should 1967 327/300HP Idle at?
#1
Pro
Thread Starter
What RPM should 1967 327/300HP Idle at?
1967 327/300HP with A/C power steering and power brakes. 3810 Holley carb. What idle RPM's should I set the carb for?
#4
Pro
Thread Starter
Sounds about right. I remembered seeing a chart in an old Corvette New mag Vol 2, No 10 and just looked it up. It says recommended idle speed RPM for standartd engine 327 cu in 4 barrel carb hydraulic lifter camshaft is 500 RPM, 700 RPM with manual transmission and Air Injectior Reactor and 600 RPM for automatic with Air Injector Reactor. So, your settings seem right in the ballpark. Thanks.
#7
Tech Contributor
With the A/C on or off?
My 65 327/350 with A/C idles around 1100 until I turn on the A/C, then it drops to 700. It might be too high, but any lower and it sounds like it wants to stall.
My 65 327/350 with A/C idles around 1100 until I turn on the A/C, then it drops to 700. It might be too high, but any lower and it sounds like it wants to stall.
#8
All
Just found dad's old Chilton Vette manual for 63. It recommends idle speed of 500 for the 327 and 700 with air. Im at 700 now w/o air and I get some dieseling on hot days so Im going to try to take it down a notch. Hopefully it doesn't run rough.
Just found dad's old Chilton Vette manual for 63. It recommends idle speed of 500 for the 327 and 700 with air. Im at 700 now w/o air and I get some dieseling on hot days so Im going to try to take it down a notch. Hopefully it doesn't run rough.
#9
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You're responding to a thread that's ELEVEN years old.
#10
Le Mans Master
But for those that don't know, the above info. is correct. Any small block running that hydraulic cam (250-300HP), if properly tuned, should idle at 500 RPM and be so smooth that you could "balance a nickle on the air cleaner".
#11
Thanks....great to know......also great you can get a response to an 11 year old thread! This forum and it's members are AWESOME! I would be stuck on the side of the road without you guys instead of enjoying my 63!
Frank
Frank
#12
Race Director
My bone stock 67 327/300 hp, powerglide in drive, factory air. I took this picture last summer to show the engine temperature on a hot So Cal day with the A/C on after installing a SPAL 16" puller fan. Idle speed looks like 700 RPM on the nose. Never runs on. I run 91 octane at the pump.
This was taken the week before I installed the SPAL 16" puller fan photo, hot day, A/C on. Looks like 700 RPM as well.
EDIT. I just noticed how the oil pressure is higher with the cooler engine temperature at the same idle speed. It's an indication that the oil is running cooler as well, evidently.
.
This was taken the week before I installed the SPAL 16" puller fan photo, hot day, A/C on. Looks like 700 RPM as well.
EDIT. I just noticed how the oil pressure is higher with the cooler engine temperature at the same idle speed. It's an indication that the oil is running cooler as well, evidently.
.
Last edited by Randy G.; 12-11-2018 at 09:09 PM.
#13
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500 in neutral with a manual trans and 450-500 in DRIVE with an automatic. With AC the idle speed-mixture adjusting procedure should be done with the compressor engaged in neutral with a manual trans and DRIVE with an automatic, so with the compressor off it will idle about 100-200 revs higher.
As previously stated it should be very smooth. If you can't achieve the above idle speed and smooth behavior the engine probably has an aftermarket cam with more overlap that the OE cam, which is not a good idea, especially with PG.
Duke
As previously stated it should be very smooth. If you can't achieve the above idle speed and smooth behavior the engine probably has an aftermarket cam with more overlap that the OE cam, which is not a good idea, especially with PG.
Duke
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Shouldn't go putt, putt, putt, PUTT, putt, PUTT, putt! Some idle like that without having anything special in the way of aftermarket cam.
Last edited by MikeM; 12-12-2018 at 10:09 AM.
#15
Awesome, Im totally stock, would like a better fan at some point. Appreciate the response. Under those conditions, I would be running temp around 220 and oil pressure around 20. As you say hotter temp and oil pressure goes down. On a cooler day i run pressure around 40/50 and temp of 180.
#16
Duke
Thanks. These specs are very helpful. I have no insight into the cam situation except being told its stock.
Thanks. These specs are very helpful. I have no insight into the cam situation except being told its stock.
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