wakawakalj wrote:This is an awesome and inspiring thread - I'm working on getting an AWD V8 build together myself, but using an S14 as a base. I've been struggling to figure out how to properly mount the front diff as the engine I'm looking at using has a steel oil pan rather than an aluminium one, and I can't weld steel to aluminium as I'm not a wizard.

Every R200 and R180 I have is NOT aluminum. That being said, I would not weld the diff directly to the pan. weld in a pass through tunnel or in my case notching the pan works out since the shaft will be up front and the sump will be in back.

I'd also like to go to something a little heavier duty than a F160 as my long term plans have me putting down a bit more power than I'd be comfortable putting through it regularly, so aftermarket alum pan + welded on GTR sump may not be the best thing anyways.

Keep in mind your typical front power output on r32/33/34 based systems will be 20% (50% MAX) whereas the rear will often see 50-100% In addition to that, the front wheels unload under acceleration so an AWD car will spin front tires before breaking front diffs.(unless you choose some tires that will also make the car hard to steer) I'm seeking the R16o for packaging reasons but I have no concerns with my modest goal of 450hp or even double that in a frot diff application.

@MY1PATH - how do you plan to mount the diff? Custom front crossmember? Or bolted to the engine somehow? I've been thinking about the possibility of a rear R200 mounted to a custom crossmember with gears cut for the Pathfinder/Xterra/Frontier high pinion R200 front diff, as my understanding is that gears in those diffs are reverse cut, which is basically mandatory for fulltime high hp AWD systems.

I plan to mount the diff directly to the engine. Engine roll will cancel out any diff roll forces generated by the front diff without transferring as many additional forces the uni-body car chassis. If you think this is a non-issue you should see how much a pathfinder front diff dances around on its mounts going over rough trails.
ONLY THE 97-04 PATHFINDERS RUN FRONT SPECIFIC R200 GEARS AND ONLY in 4.36:1 and 4.63:1 RATIOS (no alternative gear swaps available).
It is not mandatory, it just cuts down on gear noise which was an important thing for a uni-body-soccer-mom-SUV running smooth highway tires.
The 87-95 Pathfinder and 97-04 Xterra/Frontier all ran REAR GEARS in the front diff in 4.36:1, 4.63:1, 4.88:1 and 4.9:1. You can use the housing with and load other SHORT NOSE r200 ratios into it such as the Infiniti J30 4.11:1 gear set.
Speaking from personal experience, I have run thousands of miles in 4 wheel drive (50/50 split all time) over trails, snow, ice and even paved road. Not stopping to unlock hubs when I reach dry pavement and my front diffs (with rear gears) have not shown any significant wear in the 25+ years I have been with my Pathfinder. There is some additional gear noise that you have to try hard to notice over the sounds of aftermarket exhaust, modified engine, and not-so-quiet off-road tires.

MY1PATH wrote: Keep in mind your typical front power output on r32/33/34 based systems will be 20% (50% MAX) whereas the rear will often see 50-100% In addition to that, the front wheels unload under acceleration so an AWD car will spin front tires before breaking front diffs.(unless you choose some tires that will also make the car hard to steer) I'm seeking the R16o for packaging reasons but I have no concerns with my modest goal of 450hp or even double that in a frot diff application.

I remembered something and did a little digging. GTRs (cast aluminum housings) have had some grenade issues that have taken out the motor with them. The cast steel/iron housings for the r160, r180 and r200 should not suffer this issue if you use one of those for your project.

Thanks for the great info - looks like I'll be going with a short/snub nose R200 + 4.363 gears, which should work really well with my power goals and transmission gearing. I want to make this as close to bulletproof as reasonably possible and set up to handle up to ~800awhp on slicks, though I will start in the low 400 N/A range to get everything sorted before I start adding forced induction to the mix.

Now it's off to solidworks to start designing a way to attach it to the motor.