I barely post anymore but after the latest mods I felt the need. I have an ‘92 80 series with 285r16 tyres. Vehicle now has 370000km. I’m running a Gturbo with w2a ic. It’s in pretty good nik but never happy with performance at 100kmh. About 2600rpm for a 100kmh and high boost. Just meant engine was working harder than I wanted.
I decided to replace the gearbox with the 79 box. I also put in a taller 5th gear. I believe it was around .7 something. I have also swapped out the diff gears and now running 3.7s.
It has completely changed the vehicle for the better. I wished I had done it years ago. I would highly recommend doing both. If you had a NA engine I’m not sure if you would be satisfied. I have the power and now a big smile.
RPMs now sit a whisker under 1900rpm for the 100kmh. Boost isn’t sitting at 18-20psi and it’s so much quieter. Less gear changes because everything is a lot taller.
The biggest bonus is fuel. I went from a solid 400km per 80lt tank to now getting over 600km without change in driving behaviour.
It’s just great to drive.
I believe all genuine parts used in the box and some from terrain tamer. PDI supplied the diff gears. I wanted to go 3.5s but was worried about drivability off-road. 3.7s are perfect for what I do. I put in solid spacers when the diffs were rebuilt and an electric LTG4x4 diff lock in. Have t heard much about them but I’ll give it a go. I won’t be using it much.
Can’t recommend enough dropping the revs. When you start doing the math for a couple hour drive, can be over a million less revs.
I decided to replace the gearbox with the 79 box. I also put in a taller 5th gear. I believe it was around .7 something. I have also swapped out the diff gears and now running 3.7s.
It has completely changed the vehicle for the better. I wished I had done it years ago. I would highly recommend doing both. If you had a NA engine I’m not sure if you would be satisfied. I have the power and now a big smile.
RPMs now sit a whisker under 1900rpm for the 100kmh. Boost isn’t sitting at 18-20psi and it’s so much quieter. Less gear changes because everything is a lot taller.
The biggest bonus is fuel. I went from a solid 400km per 80lt tank to now getting over 600km without change in driving behaviour.
It’s just great to drive.
I believe all genuine parts used in the box and some from terrain tamer. PDI supplied the diff gears. I wanted to go 3.5s but was worried about drivability off-road. 3.7s are perfect for what I do. I put in solid spacers when the diffs were rebuilt and an electric LTG4x4 diff lock in. Have t heard much about them but I’ll give it a go. I won’t be using it much.
Can’t recommend enough dropping the revs. When you start doing the math for a couple hour drive, can be over a million less revs.
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