1hz high rpm in 5th gear

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To hell with going from r series to h series transmissions unless you can handle sheet metal, floor covering, tcase etc etc.
the cost effective solution is switch the ring and pinions to 4.10’s or 3.90’s ( i have 3.90’s w 1hdt).
 
forum.ih8mud.com

HDJ81 H151

forum.ih8mud.com forum.ih8mud.com

In 2014 i posted some info.

So R and H15x’s come in two flavors for 100/105. Separated seat (rear shift) and forward shift. The emergence for a R rear is different from H for rear. Thus changes in sheet metal. Thence changes in flooring.
Switching a h152 to separated seat included additional costs for the euro spec only parts.
If you have the pictured transfer from link above it might fit a h152, but work might be needed to confirm. Also, driveline lengths might be different as well. Shift linkages are certainly different. Bellhousings in north america are rare for h15x so expect to buy new from overseas.
H152 in US is $2550 discount plus freight and several hundred in parts and labor to swap out input (they only come in VDJ versions).
The swapped Shaft is 14 spline thus your 21 spline 1hz clutch won’t work.

Anyway. Stupid expensive route to go from R series to H series swap.
 
What you guys think of increasing tire size? Currently, it has 275/70/16 tires. Wouldn't upgrading to a bit bigger size tire bring down the tachometer needle a bit down?
It will cost me less money and save me more time, if I just go with a bit bigger size tire. I have no rooftop tent and never planning to have one or tow anything. I just like to get an ARB style front bullbar.
 
Here is the picture from inside.
IMG_3935.webp
IMG_4112.webp
 
rick_d said:
forum.ih8mud.com

HDJ81 H151

forum.ih8mud.com forum.ih8mud.com

In 2014 i posted some info.

So R and H15x’s come in two flavors for 100/105. Separated seat (rear shift) and forward shift. The emergence for a R rear is different from H for rear. Thus changes in sheet metal. Thence changes in flooring.
Switching a h152 to separated seat included additional costs for the euro spec only parts.
If you have the pictured transfer from link above it might fit a h152, but work might be needed to confirm. Also, driveline lengths might be different as well. Shift linkages are certainly different. Bellhousings in north america are rare for h15x so expect to buy new from overseas.
H152 in US is $2550 discount plus freight and several hundred in parts and labor to swap out input (they only come in VDJ versions).
The swapped Shaft is 14 spline thus your 21 spline 1hz clutch won’t work.

Anyway. Stupid expensive route to go from R series to H series swap.
Click to expand...
The is in Pakistan and there is a large marketplace for JDM car parts. Transmissions are always sold with bell housing, and you can also get money for selling yours to the person from whom you are buying.
Transmission for land cruisers are usually 1000 USD with bell housing and computer included for those transmissions that requires computer.
 
Kamran Khan said:
Wouldn't upgrading to a bit bigger size tire bring down the tachometer needle a bit down?
Click to expand...

Yes.

BUT
You'll also reduce torque. This means you have to work it harder to get moving off the line. If you're towing, or on steep hills this can be a problem.
You'll also have to change down more frequently for hills.

I had 285/75r16 (33" tire) and 4.1 did ratios in my 105. (about equal to 35" tire and stock ratios)
It reduced RPM on the highway, but I had to change to 4th for far more hills.

There's no gain in economy, and you'll find you have to concentrate on the highway more.

I had a few times when i was towing, and had to start in low range on a hill.
 
Kamran Khan said:
The is in Pakistan and there is a large marketplace for JDM car parts. Transmissions are always sold with bell housing, and you can also get money for selling yours to the person from whom you are buying.
Transmission for land cruisers are usually 1000 USD with bell housing and computer included for those transmissions that requires computer.
Click to expand...

There's not a lot to gain by changing to H151.
From memory, R151 has a deeper overdrive than H151. H151 is stronger.
 
33" tire. Or 285/75r16 will reduce RPM and torque by 5%.
Is really not noticeable in terms of engine noise.

If you're worried about noise. Better option would be remove carpet, add sound deadener and insulation to floor, firewall, wheel arches, door skins, quarter panels, and if you gwt really excited, underside of roof.

Do this right, you'll be able to make a BIG difference in noise and heat inside the car.
 
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