Top speed for 2F and 5speed? (1 Viewer)

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Installed the 5 speed but my tachometer doesn’t work. What have y’all found to be a comfortable top speed? 75?
 
FJ60 with 2F, H55F, 4.11s, 255/85/16 tires (ca. 33") flat road to low hills 2500 rpm seems to be the sweet spot which is about 70 mph but can run up to 75 at ca. 2700-2800 rpm. Mile after mile with mpg about 13 +/-
 
This is what mine looks like with true 33s and 4.11s with H55

8B4813CD-B773-4E13-9A6E-FEC97393154C.jpeg
 
Something is off on that because it would be over 3000 RPM
Depends on his diff ratios and tire diameters. Lots of ways to cruise at 100mph with an H55 at or under 3k rpm from a mathematical standpoint.

3.7 diffs and 37's measuring at 36" diameter would put you at 2935 rpm at 100 mph.

3.7 diffs and 35's measuring at 34" diameter would put you at 2953 rpm at 95 mph

On edit: I respect physics and value my life far too much to go near 100mph in a short wheelbase FJ40. But one could do so quite easily with the right combination of power, gearing and large tires.
 
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Depends on his diff ratios and tire diameters. Lots of ways to cruise at 100mph with an H55 at or under 3k rpm from a mathematical standpoint.

3.7 diffs and 37's measuring at 36" diameter would put you at 2935 rpm at 100 mph.

3.7 diffs and 35's measuring at 34" diameter would put you at 2953 rpm at 95 mph
I’m going with the Dakota is a bit off. I’m pretty sure that’s the LS/auto truck he did last year.
 
That's about all mine could muster. Tired 2F, H55, 3.70 gears, ~31" tires

Speedometer is reasonably accurate


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is


I have seen 70mph a couple of times, but I have no interest in going much faster than that. I usually avoid four lane roads just for that reason, this particular day, I had to cross the river, and there isn't any other options that don't turn it into drowning or taking a whole day. 😄
 
2F 4spd 4.11 diffs stock motor with factory carb BFG 33x10.50’s I’m running around 65mph just under 3k RPM’s.
 
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2F 5spd 4.11 diffs stock motor with factory carb BFG 33x10.50’s I’m running around 65mph just under 3k RPM’s.
How are you getting you're speed? GPS or speedo? With those #'s you should be around 23 to 2400 rpm at 65mph. H55f trans?
 
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How are you getting you're speed? GPS or speedo? With those #'s you should be around 23 to 2400 rpm at 65mph. H55f trans?
H42 trans
 
Just for fun, making some conservative assumptions about drag coefficient and frontal area, it would take 120hp to make one of these boxes move at 100mph. I dont think a normal 2f could push an FJ40 to 100mph even if you were brave enough to do it!
 
Just for fun, making some conservative assumptions about drag coefficient and frontal area, it would take 120hp to make one of these boxes move at 100mph. I dont think a normal 2f could push an FJ40 to 100mph even if you were brave enough to do it!
When I bought my LC, the drive line was a mess. Hard part failure was imminent and soon.

I really wish I would've put it on a dyno when I first got it. My guess, I was putting less than 60 hp to the ground. It struggled to hold 60mph on level ground. After going through the axles, transmission and transfer case it was better, but not life alteringly so. I'm betting I picked up 10hp. Still, a flaming turd, but there was a small noticeable increase in acceleration and ability to hold speed.

No matter what, it is worst case scenario for aerodynamics. 😄
 
Just for fun, making some conservative assumptions about drag coefficient and frontal area, it would take 120hp to make one of these boxes move at 100mph. I dont think a normal 2f could push an FJ40 to 100mph even if you were brave enough to do it!
Mine run out to the low 90s with my built Mosley motors. 40, 55, 60. Does not seem to matter drag or weight. They just stop there.

The top speed winner around here is my
3FE, H150, 4.11 truck with 34” tires.

31B7A4F7-77B4-4966-B606-FEBD4AF45FED.jpeg
 
Warthog was about 92 or so tops

2F, H55, 4.11, 33s


Cool info. What was the dyno HP # on the Warthog, to the ground?

I didn't realize how much force was on the front of these trucks until i drove 40mph with the windscreen down. It felt like I had a supercharger hooked up to my nostrils forcing air up my nose.
 
Cool info. What was the dyno HP # on the Warthog, to the ground?

I didn't realize how much force was on the front of these trucks until i drove 40mph with the windscreen down. It felt like I had a supercharger hooked up to my nostrils forcing air up my nose.

I think it was 120 hp at the wheels.
 

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