Top Speed?
Logistics Pro
Joined: May 2008
Posts: 3,670
Likes: 369
From: PHX AZ
jstephens2,
By changing the rear end gear set to a lower numerically ratio would reduce the engine rpms when at speed. However, by doing so will reduce the gear multiplication (torque) at the rear wheels. If you never tow or haul loads, you may not miss the higher gear ratio.
As OldHarlley indicated, back in the 60s, these old trucks were likely not designed nor INTENDED to be driven much over 70 mph.
Notice the advertisements from the day on these old trucks, most of the talking points were about hauling & towing and a few points about ride quality. I can't say I've seen any ads referencing top speed abilities. Now did these trucks have some sort of governor system or rev limiter? - No. So are they capable of speeds over 70 mph? - sure. But it wasn't a priority when they were built back in the day.
Which brings us to, "How fast can they be driven SAFELY?" BOSS9F100 says he'll soon have his '66 F100 capable to attain 140 mph. I'm confident that he'll have modified the OEM suspension & drivetrain to be driven SAFELY at those speeds. Now some here will claim they've driven their OEM 40+ yr old truck beyond 70/80 mph....some specifying to only try it on a clear, smooth, big road. Such a run would be preferred to be conducted in broad daylight, as the OEM headlights did not provide good vision in the darkness at higher speeds.
If you plan to find the 'top end' of your ol' truck, please first ensure you're confident that the steering and brakes are in the BEST CONDITION THEY CAN BE to allow you the peak control it can afford.
I prefer to drive & enjoy these ol' trucks as they were intended, for hauling and towing and driving under 70mph. When I want to go faster, I will jump into a Mustang or similar 'speed intended' vehicle... JMHO.
BarnieTrk
By changing the rear end gear set to a lower numerically ratio would reduce the engine rpms when at speed. However, by doing so will reduce the gear multiplication (torque) at the rear wheels. If you never tow or haul loads, you may not miss the higher gear ratio.
As OldHarlley indicated, back in the 60s, these old trucks were likely not designed nor INTENDED to be driven much over 70 mph.
Notice the advertisements from the day on these old trucks, most of the talking points were about hauling & towing and a few points about ride quality. I can't say I've seen any ads referencing top speed abilities. Now did these trucks have some sort of governor system or rev limiter? - No. So are they capable of speeds over 70 mph? - sure. But it wasn't a priority when they were built back in the day.
Which brings us to, "How fast can they be driven SAFELY?" BOSS9F100 says he'll soon have his '66 F100 capable to attain 140 mph. I'm confident that he'll have modified the OEM suspension & drivetrain to be driven SAFELY at those speeds. Now some here will claim they've driven their OEM 40+ yr old truck beyond 70/80 mph....some specifying to only try it on a clear, smooth, big road. Such a run would be preferred to be conducted in broad daylight, as the OEM headlights did not provide good vision in the darkness at higher speeds.
If you plan to find the 'top end' of your ol' truck, please first ensure you're confident that the steering and brakes are in the BEST CONDITION THEY CAN BE to allow you the peak control it can afford.
I prefer to drive & enjoy these ol' trucks as they were intended, for hauling and towing and driving under 70mph. When I want to go faster, I will jump into a Mustang or similar 'speed intended' vehicle... JMHO.
BarnieTrk
It runs 35 mph per 1000 rpm. 2800 rpm @ 100 mph.
Tuned
Joined: Feb 2017
Posts: 324
Likes: 6
From: SoCal
My 65 has been up to 90mph and still had plenty left to give. I figure I could reach the 120 peg if I wanted to but I prefer to keep it around 70-80mph on the freeway. Not to mention that my 10mpg drops scary low when speeding for too long.
Logistics Pro
Joined: May 2008
Posts: 3,670
Likes: 369
From: PHX AZ
And then you woke up at bottom of grand canyon realizing it was only a couple thousand feet not all day . .
Logistics Pro
Joined: May 2008
Posts: 3,670
Likes: 369
From: PHX AZ
Truck 1 did 105 quarter @ 13.0 being 4700 lbs effortless to cruise @ 100 mph 1966 F250
Truck 2 current build has a 6 cylinder and should run 11's in the 1/4 mile. Prob never dare try top speed but cruising all day @ 80+ no problem 1966 F250
Truck 3 Short bed should also run 11's in 1/4 no question it should go 140+ 1966 F100
Truck 4 Should run 12's in 1/4 mile and easily cruise 80 mph all day long with a 170 cu in engine. Its a 1966 F100 4x4 and prob get 25 mpg @ 65 mph
Truck 5 being 7000 lb plus should run 130 in quarter mile and its a BBF
Truck 6 is a 3.0 FWD no clue on speed but 80 mph cruise all day no problem.
Senior User
Joined: Jun 2017
Posts: 106
Likes: 0
"Truck 2 current build has a 6 cylinder and should run 11's in the 1/4 mile. Prob never dare try top speed but cruising all day @ 80+ no problem 1966 F250"
ok, now you've got me super interested in what you've got going with the sixer.
I just grabbed the clifford 2x2 and header setup for my '66 F250. yet to go on, but I have run 11's in the 1/4 and that's bloody fast. taking this behemoth down the track that fast with a 6 has to be quite a setup...one I don't foresee in my future..
mine sitting the way it is....I would need an MX missle crammed up its butt to do 11's
can I ask how?
ok, now you've got me super interested in what you've got going with the sixer.
I just grabbed the clifford 2x2 and header setup for my '66 F250. yet to go on, but I have run 11's in the 1/4 and that's bloody fast. taking this behemoth down the track that fast with a 6 has to be quite a setup...one I don't foresee in my future..
mine sitting the way it is....I would need an MX missle crammed up its butt to do 11's
can I ask how?
Lead Gopher
Joined: Aug 2012
Posts: 10,014
Likes: 1,565
From: Seattle
This thread is hilarious. It went from a guy asking in 2011 if he should be able to do better than 60-65 on the highway. Now we are up to 150 on the racetrack! Lol. Hahaha.
I like it!
Chad
I like it!
Chad
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Logistics Pro
Joined: Feb 2011
Posts: 3,522
Likes: 11
From: Townsend, MT
Direct injection, turbocharging, intercooling - it all adds up.
Logistics Pro
Joined: May 2008
Posts: 3,670
Likes: 369
From: PHX AZ
"Truck 2 current build has a 6 cylinder and should run 11's in the 1/4 mile. Prob never dare try top speed but cruising all day @ 80+ no problem 1966 F250"
ok, now you've got me super interested in what you've got going with the sixer.
I just grabbed the clifford 2x2 and header setup for my '66 F250. yet to go on, but I have run 11's in the 1/4 and that's bloody fast. taking this behemoth down the track that fast with a 6 has to be quite a setup...one I don't foresee in my future..
mine sitting the way it is....I would need an MX missle crammed up its butt to do 11's
can I ask how?
ok, now you've got me super interested in what you've got going with the sixer.
I just grabbed the clifford 2x2 and header setup for my '66 F250. yet to go on, but I have run 11's in the 1/4 and that's bloody fast. taking this behemoth down the track that fast with a 6 has to be quite a setup...one I don't foresee in my future..
mine sitting the way it is....I would need an MX missle crammed up its butt to do 11's
can I ask how?
The amazing truck will be the F100 4x4 that will run 12's on only 170 cu in. but still get great MPG and SPG
Logistics Pro
Joined: May 2008
Posts: 3,670
Likes: 369
From: PHX AZ
When one has PPG heavy duty stir sticks one can let 'er rip.
Logistics Pro
Joined: May 2008
Posts: 3,670
Likes: 369
From: PHX AZ
150 mph would be only 5000 RPM. That's doable if one were brave enough to hold er down
Logistics Pro
Joined: May 2008
Posts: 3,670
Likes: 369
From: PHX AZ
"Truck 2 current build has a 6 cylinder and should run 11's in the 1/4 mile. Prob never dare try top speed but cruising all day @ 80+ no problem 1966 F250"
ok, now you've got me super interested in what you've got going with the sixer.
I just grabbed the clifford 2x2 and header setup for my '66 F250. yet to go on, but I have run 11's in the 1/4 and that's bloody fast. taking this behemoth down the track that fast with a 6 has to be quite a setup...one I don't foresee in my future..
mine sitting the way it is....I would need an MX missle crammed up its butt to do 11's
can I ask how?
ok, now you've got me super interested in what you've got going with the sixer.
I just grabbed the clifford 2x2 and header setup for my '66 F250. yet to go on, but I have run 11's in the 1/4 and that's bloody fast. taking this behemoth down the track that fast with a 6 has to be quite a setup...one I don't foresee in my future..
mine sitting the way it is....I would need an MX missle crammed up its butt to do 11's
can I ask how?
170 cu in sounded good its actually 164.7641 cu in or 2.7 Liter as from a 2015 EcoBoost F150. It will have the 2.7 tuned to about 390 RWHP and would guess it will be well under 4000 lb. It also has electronic locking axles (3.55's) on front and rear. A Boosted Launch should get it into the 12's. I left out just a "few" pertinent details because I happened to have the PPG Heavy Duty paint stick in my hand.
The other 1966 F250's may be six cylinders but both have 3.5 EcoBoost engines. Current build has the 2017 Ford GT Turbo's on it so should make 480-500 RWHP and 550 lb ft torque. Being 3700-3800 lbs the picture has been "photoshopped" Yeah its only a 6 (six) but when you read the small script .. I was getting bored spending so much time on these trucks had to take a break.
