Jump to content

3.13 differential with limited slip


302MGB
 Share

Recommended Posts

The exploded view in the '05 service manual shows a two-pinion open diff, which another illustration shows dressed up with a finned diff cover. Perhaps that cover is where your source got the idea that there was something else going on inside. Have a look for yourself, I didn't bother reading through the whole thing and may well have missed something. I don't think there are many R51 guys on here, so if you want firsthand info, you may need to try other forums.

 

Also, I have to ask... does 302MGB refer to a little British car with a Ford V8 in it? I ask because my dad and I are in the process of shoehorning a 302 into his Triumph. Should be ludicrous once it's back together. :lol:

Link to comment
Share on other sites

Thanks for that info Startbartfast. For some reason the link won't open on my phone so I'll have to look when I'm at a PC - but sounds like what I was afraid of but didn't want to hear.

 

As for 302MGB, yes, I swapped the drivetrain in my MG to a 302/T5 combination from a Mustang and custom IRS using the short nose Nissan R200 differential (mine's from a JDM Skyline). You can see pics of my build here: http://www.britishv8.org/MG/RobFicalora.htm. BritishV8.org is a great board for British car engine swaps. And, we get together somewhere in the US every year. 2018 is Dayton OH in July. You/your dad should check it out. What model Triumph are you guys doing?

Link to comment
Share on other sites

Nice build! Looks like a lot of work went into the suspension. My dad's is a '67 TR4A, at least from the doors forward--some nut hacked off the back end and spliced in TR6 sheet metal from the B pillars back. We're not entirely sure why. But since it was "wrong" already, we figured we might as well go crazy with it. Same Mustang 302/T5 you went with, though we're leaving the suspension stock for now (and hoping the rear axle can take it). We've studied a few of the builds on Triumph V8 for ideas! Dayton's a little far but we're hoping to make the all-British field meet in Seattle one of these years. I've made a few videos of the build process so far--lots left to do!

Link to comment
Share on other sites

Looks like you guys are well on your way. I've always loved TR-4/4A's. But for some inspiration, check out my buddy Calvin's TR-6... http://www.britishv8.org/Triumph/CalvinGrannis.htm

 

Looks like I'm SOL on a 3.13 with limited slip. I'm still checking to see if I can put the 3.13 ring and pinion in my Skyline diff. If not, I'm going to gave to rebuild my IRS using some other diff.

Link to comment
Share on other sites

Jesus, that's a motor! He did a really clean job on it, too. :aok: I showed my dad the exhaust routing, that's something we'll need to tackle pretty soon on his. Seeing builds where you guys go all out on suspension makes it seem like our simple engine swap should be done by now. :lol:

 

I did a search and Hawairish (forum axle expert) says in this thread (near the end of post #2) that the R51 has an R200/R200A rear end--looks like your Skyline rear is also an R200, so unless Nissan did something bizarre, your gearing swap might just work.

Link to comment
Share on other sites

Very long story short from a PM reply, 3.13 (47:15) gears exist in the 05-09 R51 V6 2WD (and probably 10-12) as the R200 rear diff w/ IRS, and similar year Frontier D40 and Xterra N40 models (presumably 2WD) that got the C200 straight axle instead of the Dana axles. I only cross-ref'd parts far enough to say the ring and pinion should fit 03-17 350Z/370Z/G35/G37 R200V VLSD diffs based on the same front bearing, rear bearing, spacer, and shims for the pinion, but next step is trying to cross-ref to older 240SX and 300ZX Turbo R200V diffs, since his 96 Skyline assembly appears to share part numbers with.

 

Several other Nissans and Infinitis have used the R200 rear diffs since mid 90s, mainly V6 AWD/RWD cars and V6 SUVs like the R51 and FX35/FX37/QX70, but I suspect only the cars had VLSD options. The V8 models got the R230. I presume all the newer ones use the 6-bolt axle stubs instead of the 5-bolt, and there's probably a change in spline count and shaft diameter.

 

If the 3.13 gears can fit the older housing, I'd imagine it'd work with the older bearings and spacers. On the flip side, since carrier dimensions among C200 and R200 variants were pretty much identical, I'd think the old VLSD carrier would fit the newer R200/R200V housings, but casting from the housing around where the ABS tone rings would probably need to be removed to clear the 5-bolt stubs, and the stub seals would likely have to be used (assuming the outer diameter of the seal hasn't changed). If I'm not mistaken, the chassis mounting pattern on the R200 hasn't changed much over the years, and might be the same as the R230 unless. That would at least give hope that you could get a Z/G VLSD that would bolt onto your chassis, but you'd still need the R51 diff to get the 3.13 or 3.357 (47:14) gears, and work out any differences on the stub shafts or driveshaft flange (that could likely be swapped).

 

 

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...