By having a none x (no awd) you sir lucked out. It’s alot harder to do the front diff and rear diff than rear. None the less both. I’would look at Z1 Motorsports website and just do their rear diff package and pick out what all options you want.

You have a bunch of options in gearing to go to being just rwd. I think you can choose all the way down to 3.1 final drive and all the way up to 4.08. If I was you, I would read some of the reviews for the 3:9/4.08 gears. Some people really love it. 3.69 is as high as it goes for the x, without being extremely expensive.

Fast intentions said “flex plate is roughly 2 pounds heavier than OEM due to it being sold aluminum with no window cuts.”

I’m sure it’s a typo and it ment to say “solid” instead of sold. Just a fun fact. I thought it would be lighter until I held them side by side. I know it’s only 2 lbs but weird enough you can actually tell a difference in weight. Lol I was told if I’m worried about the weight, loose it somewhere else hahahahaha

So the trans is done today!!!! It’s built and just needs to be filled up with 11qts oem matic s (level 10 calibrates transmission to run off of this fluid not anything else). $900 labor for install parts into trans.
Breakdown. Paid $500 for a 7at trans, bought exedy clutch kit $500, level 10 vb and tq converter was $1800, and the flex plate $800. I saved around $1000 out the door building the trans myself locally. Yes I saved money because I’m sure level 10 would of done more work to hold more power but I will never see more than 550 whp on this car so I saved that $1000 to buy another nitrous kit. Could of just done the level 10 bullet proof trans for 5k. Still would of had to buy fluid and the $800 flex plate but that’s it. Pat from level 10 laughed when I asked him if this setup will hold a 150 shot of nitrous and extreme daily abuse. Definitely no issue. Also didn’t opt for the custom shims from fast intentions since I’ll be no where near a place where I would need them.

Now we are working out the diff and other small tasks. Got a vlsd rear diff going in, wondering how that’s going to feel compared to my open rear diff I have now.
What all is getting done.
Raise headlights up
Heat wrap headers
Trans/power steering cooler install
Replace power steering pressure switch
Sub frame collars
Install z1 motor mounts
Custom mount a black mishimoto universal coolant reservoir
Fix the a/c (won’t charge Freon blows hot air but compressor works)
Install z1 master cylinder brace
Swap the correct rib count serp belt and inspect all the pulleys with belt off
Flex plate install
Swap diffs and bushings
Swap built trans back into car
Power steering boot leak. Replace both sides.
Also Uprev shows a code of p0550 (power steering pressure sensor) so replace that also.
Make car more aero/braces underneath

Going to ride out the stock driveshaft till the new one comes in. Haven’t ordered yet. Making sure measuremenrs don’t change since I changed the diffs. Also curious if I lost weight between the g35 diffs and my g37x diffs. The g35 ones are extremely light. Haven’t held the g37x ones yet they might be just as light.

Eagerly awaiting review of the G35 diff/gearing change. I may possibly be more excited than you are. I have diffs available to me, just awaiting news on your build to drop the hammer on them.

Zer099 has completed the swap already. He’s local to me also. He has a lot of knowledge on the swap. My mechanic says he has swapped front diff before and had no issues. Quoted around 600-700 labor to swap front and rear diffs and bushings. I was assured these diffs will work. But we’ll see, I’ll let you know. Should have it back in a week. Lol lots of hiccups so far but it happens when you go this far down the rabbit hole lol

Only issue not resolved yet on this build is the one piece rear driveshaft.

Yeah man. You’re going foot to the wood with the drivetrain. I am just so curious to see how the gear ratio change goes.

No problem!

Oem flex plate. Going to replace with orange flex plate pictured below. Camera is where transmission sits

Top left is a g35 lsd diff, underneath is z1 rear diff cover
Second from the top on left is front diff from g35x.
Whiteline bushings and underneath that is new boots for the rack.
Sub frame collar bottom right of pic
Flex plate (orange in picture)
Stall converter (silver circle with red cap)
Power steering and trans cooler (black squares)

Everything in just waiting on driveshaft!!
Warped my centric blanks I had on. Swapping to these. Slotted only though. I’ll be upgrading to a bbk in some time. For now this works since I have hard time finding something to clear my 17 inch rpf1
Swapping back to these from the posi quiet. Parking brake is posi quiet
3 coolers pictured. Left side is the trans cooler. Exactly next to it to the right is the oil cooler. In front of oil cooler and the trans cooler (mounted at same height as other coolers just moved 10 inches forward or so) is the power steering cooler.
Power steering cooler.
So the diff swap and trans install went fine. We wanted to wait till after we swapped diffs just to make sure we had the right size. Driveshaft shop has a 6 WEEK wait on custom driveshafts. Ended up having to do a custom local one piece aluminum driveshaft. Also going to cost me $1000 for just the aluminum. Not happy about it at all, really really wanted one from thedriveshaftshop but can’t wait 6 weeks. The oem one won’t fit? The local shop is going to have it custom made and ready on Tuesday for install and balanced to 9k rpm. After this driveshaft is installed, this part of the build will be complete. Then we do the break in period on trans. Going real easy on it for a month. Needs a bunch of heat cycles. I have to change the fluid every 1000 miles for 3k miles. So 3 times I will have to drain and fill. Not entirely sure why 1k miles then change but I’m guessing they look at oil make sure no shavings. Also I was told my last trans the fluid was burnt up. I’m sure they test the oil make sure stuff is good? All guesses here.

Hey buddy, I’ll get a few detailed pictures for ya on Monday and upload it. They are actually rerouting the lines and swapping some of the fittings around that have the different degree angles to make it go where they want it to. Changing it up from the way I’ve had it for 2 years. I’ll be sure to post up the new setup. They said it could be routed better than I did it. Which isn’t hard to believe because I just put it in however it would fit. But I can say that I’m extremely excited to have the lines rerouted and setup updated. Currently right next to the front sway bar is the oil filter. Well that Thermostat plate has a weird angle on it and if I bottom out hard it will brake the fitting off to the oil lines and spew out oil everywhere. This actually has happened before (mentioned somewhere in this thread)

Fingers crossed.

Found out why the driveshaft is so expensive ($1000)

Because we swapped the rear diff to a Z diff with a Z flange, it doesn’t have any room for slip. There’s no slip yoke in a awd trans it’s a flange end. It will be a one piece shaft with a slip joint in the center.

Ok this is a normal driveshaft


See on the left side how it has a “slip” yoke. That slides inside the transmission and then allows you to slide the other end up into place and bolt it to the diff

The awd trans doesn’t have a hole for a slip yoke to go into. It has the same flange as a diff does.
See how both ends are a 4 bolt flange. So when both sides are a 4 bolt flange you have to add a slide joint inside the driveshaft. That way you can compress the driveshaft just a little to get it up into the trans and then when you tighten it against the trans and the diff it will slip back into the proper length