2H first drive impressions

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bull

bull

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Took the family out in the troopy today. Our maiden voyage, everyone loves it! We filled up with B99 and got on the freeway to take it for a spin. Everything is tight and runs great. The only real concern for me is that going 60mph/100kmh the 2H was running around 3000 RPM.

Is that an ok rpm for a non-turbo 2H? I'm guessing from the RPM 3000, the tire size 235/85/16, and speed 60mph that the gear ration in the HJ47 is 4.11.

Is there a pro vs con in running 3000 rpms on the freeway? Going to lift it tomorrow and put 33" tires so I will get probably a 400rpm drop.


thoughts?
 
I think 3000 is a little high but both my 70 series have a 4.11 and when in 4th gear which is 1:1 they are doing about 2600 rpm or less at that speed.
I was wondering if either your speedo or tacho was out?

Im going to double check today if I get on the freeway and welcome to the diesel club;)
 
bull said:
what size tires do you have?
Click to expand...

I have 33 and 31 but that wont make a difference as what you read on the speedo is directly related to what you read on the tacho.

I double checked and I'm getting 2600 when the speedo says 100kph.I had a 61 series and it was getting about the same readings as the 73 and 75 series I have now
Im guessing,but at 3000 rpm I would be reading about 110+ on the speedo
 
"Is that an ok rpm for a non-turbo 2H? I'm guessing from the RPM 3000, the tire size 235/85/16, and speed 60mph that the gear ration in the HJ47 is 4.11."

My 2H with 31"/15's and 4:11 runs about 2500 rpm at 60mph.
 
Remember guys, this is a troopy, not a more arodynamic 60 or 70 series, his revs will probably be a bit higher, cause he will be pushing more air with that buldozer 40series windshield.
Cheers,
Deny
 
Deny said:
Remember guys, this is a troopy, not a more arodynamic 60 or 70 series, his revs will probably be a bit higher, cause he will be pushing more air with that buldozer 40series windshield.
Cheers,
Deny
Click to expand...
Aerodynamics have nothing to do with rpms
 
Is there a pro vs con in running 3000 rpms on the freeway? Going to lift it tomorrow and put 33" tires so I will get probably a 400rpm drop.


thoughts?

No doubt you will use more fuel at 3,000 rpm the 2H use less at a lower revs even with the 5 speed box. The lift and 33s will also make it use more fuel and less performance will result. The troopys become top heavy pretty quick on uneven ground with a lift and loading the roof rack is a bad idea with a lift and off road. cheers.
 
My HJ60 runs at about 3000 rpms in 4th at 68-70 mph. At 3300-3400, I can sustain 80 mph without heating up too badly. After that, the temp will rise and I must slow down. I believe my top end, on a level stretch of road is about 88 mph (142 kph), precisely enough speed to engage my flux capacitor!
 
hks3sgte said:
Plus you have to compare gear ratios. 1:1 vs the fifth gear on the H55
Click to expand...

Already taken into account .The 4th on a 5 sp is the same as a 4 sp ,1:1
In 5th gear with 4.11 diffs I get about 2200 rpms at 100kph

As to the original question very few diesels are designed to be driven at above 3000 and I would keep them under that except for short bursts.

I think the Landrover TD5 can sit on 3700 for extended periods
 
MyHJ60Sheila said:
My HJ60 runs at about 3000 rpms in 4th at 68-70 mph. At 3300-3400, I can sustain 80 mph without heating up too badly. After that, the temp will rise and I must slow down. I believe my top end, on a level stretch of road is about 88 mph (142 kph), precisely enough speed to engage my flux capacitor!
Click to expand...

Well, I don't have the balls to do this to my truck. I have only exceeded 3000rpm a couple of times and only on full load when preparing to shift.
 
On my way home today I verified my rpms and speed. At 3000 rpms, I am going ~108kph (67 mph). At 3500 rpms, I am at 133-135 kph (~82 mph), depending on the incline. I can get to 88 mph (142 kph), but it is well into the red and I am sweating bullets, especially when the truck starts lighting up with all that electricity and the flux capacitor is discharging those 1.21 gigawatts...
 
Tyres dont alter anything on the speedo/tacho readings. The speedo and tacho are both connected to the drivetrain.
The faster the engine spins,the higher the tacho and speedo reading. The speedo is connected to the gearbox/t/case,so if you double the engine speed you will always double the speedo reading in any given gear.

However if you add bigger tyres your REAL speed will increase but your speedo will only show the same speed in relation to rpm.
So basically in this case ,at 2600 rpm(approx)you will always read 100kph on the speedo in 4th gear with 4.11
The only way to get around this is to recalibrate the speedo,use a GPS or work out the real speed with a calculator

If a 2H and a 1HZ are running the same gearbox and diff then they will achieve the same readings if the rpm is the same.
However if one had bigger tyres ,it would overtake the other;)
 
Deny said:
Remember guys, this is a troopy, not a more arodynamic 60 or 70 series, his revs will probably be a bit higher, cause he will be pushing more air with that buldozer 40series windshield.
Cheers,
Deny
Click to expand...

only if your clutch is slipping :D:D:D
 
roscoFJ73 said:
Tyres dont alter anything on the speedo/tacho readings. The speedo and tacho are both connected to the drivetrain.
The faster the engine spins,the higher the tacho and speedo reading. The speedo is connected to the gearbox/t/case,so if you double the engine speed you will always double the speedo reading in any given gear.

However if you add bigger tyres your REAL speed will increase but your speedo will only show the same speed in relation to rpm.
So basically in this case ,at 2600 rpm(approx)you will always read 100kph on the speedo in 4th gear with 4.11
The only way to get around this is to recalibrate the speedo,use a GPS or work out the real speed with a calculator

If a 2H and a 1HZ are running the same gearbox and diff then they will achieve the same readings if the rpm is the same.
However if one had bigger tyres ,it would overtake the other;)
Click to expand...

You just contridicted yourself all in the same post. :flipoff2:


Tires size will affect speedometer readings. If you go bigger than stock tires your speedometer will read a % slower than you are really going.
 
bull said:
You just contridicted yourself all in the same post. :flipoff2:


Tires size will affect speedometer readings. If you go bigger than stock tires your speedometer will read a % slower than you are really going.
Click to expand...

No I did not :D,I differentiated between speed as read and REAL speed.

Here it is "However if you add bigger tyres your REAL speed will increase but your speedo will only show the same speed in relation to rpm."

eg If at 2000 rpm your speedo says 50 mph then at 4000rpm the speedo will read 100mph
However if you put tyres on with a 10% bigger circumference it will increase your REAL speed accordingly to 55 mph and 110 mph but the speedo will still read 50 and 100 mph at 2000 and 4000 rpm respectively ;)

Your speedo and tacho are connected to the same piece of spinning junk and will ALWAYS be in sync with each other
 
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