Cruise RPM?

[ssffnomad]

Really ? ? ?
True Story ? ? ?
Stretch

[Tinker]

Originally Posted by Ol' Ron

Between 2000/2500 rpm air/fuel ratio in the low 15.
Gramps

I like this assessment about what was asked. This sounds better to me for longevity of the motor internals. Better then just run the poop out of it.

It might be okay to explore all the other options to get it going faster with less rpms. certainly over long distances.

Trans and diff gearing, tires, od....

[TomT/Williamsburg]

I have said this before. A wise Flathead guru from a long time ago told me that flatties need heat to run efficiently. The Rprange to stay in he said is between 2000-2800 rpm. Running a 5-speed with a .86 5th gear, 32” tall tires, and 3:54 banjo rear (my avatar) @2500 rpm I am running right around 75 and at 2800 I am at 86 mph (and I have sustained 86 for 2 hours except when I hit a headwind and lose 3 mph due to the weight of all the extra parts I carry “just in case”)! She is one long distance runner with 3 cross country trips to prove it.

All kidding aside, I can tell you my nearly stock flattie does not sound like it’s straining nor does it know the difference one bit at 2000, 2500, or 2800 rpm - she just loves it as do I!

I wish every Flathead owner the same fortune ……

[Tinker]

My stock-ish 38 truck has a basic 60 over single carb. 7.00 tires, 3.78 rear, and a Mitchell 36% od.


I can get it rolling at low rpm (ear only, no tach... no lug) up to 65-70. Top I've taken it to 75. It had room to keep going but maybe not road at low rpm. I'm running out of gears. Need a 12 sp trans. Temp never much near 180 if the gauges are good. Only talking 20 miles, guess I need to stretch it's legs.

[V8COOPMAN]

Originally Posted by ssffnomad

Really ? ? ?
True Story ? ? ?
Stretch

True scoop! Jim Miles was the builder/regular driver. He began to get "spooked" about driving the car after rolling the first Fiat-bodied car through the lights the year before. So engine builder Gary Essman was driving that night in '65. Engine was a 331 Hemi out of the first Fiat car with a 1/2" C&T crank. DD

.

[Will D]

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Where are you guys trying to get to in such a hurry? I putt along at 55mph and enjoy the ride. Double lanes, and pull outs aren't there for no reason

[ford38v8]

Originally Posted by Will D

Where are you guys trying to get to in such a hurry? I putt along at 55mph and enjoy the ride. Double lanes, and pull outs aren't there for no reason

When you're on the Nevada desert mid day, you don't stop to smell the flowers.

[JayChicago]

Originally Posted by Will D

Where are you guys trying to get to in such a hurry? I putt along at 55mph and enjoy the ride.

Me too. I drive the Interstates in the right lane, wave back at the smiling faces in the passing cars flashing the thumbs up. When driving the old car I'm doing what I love to do. No hurry to get to the destination; no hurry to end the fun.