The "just bought it thread" ----> here
A caveat before we start - this BJ42 is all original and I will not be the PO who hacks it all up. I have another build that is all custom but all mods on this 42 must be "un-doable". I intend a full nut and bolt restoration on this truck some day and have been collecting parts to that end already.
After 22,000 km last year I have a few things I want to change for the upcoming wheeling season.
These are the issues:
1) Power. Need some. The normally asphyxiated 3B has enough power to tool around the city with no issues at all. Her favorite speed is right around 80km/h. The highway is another matter. With no wind on level ground she'll do 110km/h with relative ease. A headwind or any incline whatsoever is like throwing out an anchor. And most of the 22k km last year was hwy.
2) Gearing. The current gearing is all stock H42/2.28/4.11 with 10% rubber overdrive. It works good but can be stressful on certain high risk obstacles. Without enough power to push through I have often stalled at quite inconvenient times.
3) Front diff. It's open and I had at least three specific occasions where a front locker would have gotten me through.
My solutions are:
1) Turbo. Go head and say it Josh.
2a) Advance Adapter's 4:1 transfer case gears.
2b) H55f
3) ARB and compressor.
I will be pulling the entire stock original drive train out and mothballing it for that future restoration. There is nothing wrong with it and only 200k on the clock.
I had a 3B rebuilt at great cost for my 45 project using many new components and a t3/t4 turbo. The 45 project is going another direction and this engine is getting dusty. I sourced an H55f/splitcase (from Behemoth60) out of a 86 BJ70 but it has over 650,000km on it. I also purchased a brand new H55f from Beno and AA's 4:1 gears purchased through Kurt.
This combo does a number of things differently than the stock train did. Turbo for more power. 5 speed gives lower first gear and a 15% overdrive. The 4:1 case gears give me a 77:1 low/low and another benefit. The lesser known effect of the 4:1 AA gears is the 10% under-drive in high range. At first I thought that was a bad thing until I realized that the 33" KM2's give me near enough to a 10% rubber overdrive.
Net effect is a corrected speedo and 5% overdrive with a turbo to power it and low enough crawl to stop a lot of the herky-jerkies.
Feel free to point out any errors in my math. Here are some pictures.
The 42
The 3B originally built for my 45
The new H55f from Beno
A caveat before we start - this BJ42 is all original and I will not be the PO who hacks it all up. I have another build that is all custom but all mods on this 42 must be "un-doable". I intend a full nut and bolt restoration on this truck some day and have been collecting parts to that end already.
After 22,000 km last year I have a few things I want to change for the upcoming wheeling season.
These are the issues:
1) Power. Need some. The normally asphyxiated 3B has enough power to tool around the city with no issues at all. Her favorite speed is right around 80km/h. The highway is another matter. With no wind on level ground she'll do 110km/h with relative ease. A headwind or any incline whatsoever is like throwing out an anchor. And most of the 22k km last year was hwy.
2) Gearing. The current gearing is all stock H42/2.28/4.11 with 10% rubber overdrive. It works good but can be stressful on certain high risk obstacles. Without enough power to push through I have often stalled at quite inconvenient times.
3) Front diff. It's open and I had at least three specific occasions where a front locker would have gotten me through.
My solutions are:
1) Turbo. Go head and say it Josh.
2a) Advance Adapter's 4:1 transfer case gears.
2b) H55f
3) ARB and compressor.
I will be pulling the entire stock original drive train out and mothballing it for that future restoration. There is nothing wrong with it and only 200k on the clock.
I had a 3B rebuilt at great cost for my 45 project using many new components and a t3/t4 turbo. The 45 project is going another direction and this engine is getting dusty. I sourced an H55f/splitcase (from Behemoth60) out of a 86 BJ70 but it has over 650,000km on it. I also purchased a brand new H55f from Beno and AA's 4:1 gears purchased through Kurt.
This combo does a number of things differently than the stock train did. Turbo for more power. 5 speed gives lower first gear and a 15% overdrive. The 4:1 case gears give me a 77:1 low/low and another benefit. The lesser known effect of the 4:1 AA gears is the 10% under-drive in high range. At first I thought that was a bad thing until I realized that the 33" KM2's give me near enough to a 10% rubber overdrive.
Net effect is a corrected speedo and 5% overdrive with a turbo to power it and low enough crawl to stop a lot of the herky-jerkies.
Feel free to point out any errors in my math. Here are some pictures.
The 42
The 3B originally built for my 45
The new H55f from Beno
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