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-   -   Billet diff case? (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/billet-diff-case-1154735/)

Billj747 06-14-23 01:47 AM


Originally Posted by mr2peak (Post 12563898)
I didn't come up with $700 for the cover, that was Billj747 in post #43, not sure why he's pointing at me? However, that is what they cost. The cheaper options, like the Greddy, are sand cast.

Yes you did, post #22 dude...


Originally Posted by mr2peak (Post 12563898)
OS-G super lock shouldn't chatter, but it's also one of the most expensive options. The KAZZ is known to chatter, less plate clutch pairs with a shorter life, but plenty good for most people.

They do. I have one in my NSX and will be swapping it out for a wavetrac. I've also used them in RX8s, EVOs, 350Zs, and countless other cars along with writing this article on how to tune them:

https://motoiq.com/project-nsx-part-...ifferential/3/


Originally Posted by mr2peak (Post 12563898)
Sure, the 8.8 is a great option if you don't mind cutting up your subframe, welding, and moving on from the stock style parts. Some of us, for better or worse, want to keep the FD as true as possible to its origin. I'd argue people looking for an upgraded FD trans with a billet main shaft vs swapping to a CD009 or similar, might want to stick with the OEM style housing along with a true motorsports clutch type diff for reasons other than pure rationality. Modding cars isn't really rational anyway, try justifying why you own an old rotary without resorting to "because it's just so cool".

Billet diff housings exists for other platforms. I guess those guys are all idiots for not just swapping in an 8.8?

Should we all just LS swap? Hell, just go buy a Tesla and get over-the-air mods..

It appears you haven't looked into the Ford 8.8" install. There is not 'cutting' of the subframe. You simply drop the subframe then weld in the "X" brace at 4 points on your subframe, and then the Ford 8.8" diff bolts right in. The driveshaft is essentially the same length as stock but requires the Ford bolt pattern by modifying the Ford flange or the driveshaft. Many cars from Supras to BMWs and GT86s are now using Ford 8.8" because of how strong they are. Other cars may not have the room to fit the diff and thus require a billet option 4-times the price or more.

It all depends on the usage and need. For around an extra $1,000 I would prefer a bulletproof diff and axle setup that does not chatter like an OS Giken (let alone KAAZ). If the chatter does not bother you and if your usage and power won't break the stock 8" ring and pinion or axles, the OS Giken and brace/girdle is a less expensive option that's probably good for most.

TeamRX8 06-14-23 11:41 AM

^^^^
https://cimg4.ibsrv.net/gimg/www.rx7...e5956a05d.jpeg
.

mr2peak 06-14-23 01:16 PM

My bad Billj747, I wrote that a few months ago. At least I backed it up by saying that's a realistic price. The B2A billet cover is $800, seems insane honestly. The cover doesn't break anyway, it's the nose of the diff that snaps off. The gas tank blocks most of the cover bling anyway, but I guess it has it's place.

Just checked out the MotoIQ article you wrote, "The OS Giken LSD has some of the smoothest operation of any aftermarket LSD we have tested with minimal to no noticeable ‘chattering’ side effects." Is this something that developed later on once you put more miles on the diff? Or did you change something else in clutch pack / spring setup that lead to more chatter?

No Wavetrac for the FD case, that's another solid argument for going 8.8

It's a 2 rotor on pump so I doubt I'll be breaking axels. Nothing else on this car is prepared for that level anyway.


Originally Posted by TeamRX8 (Post 12564087)

If you feel like coming to this thread to help and add info, like talking about a Winters QC, I'm all ears. Otherwise try to keep the personal stuff in the politics forum where it belongs, you're welcome to come back there and insult me as much as you want.

mr2peak 06-15-23 06:46 AM

@Billj747 I live in Thailand, getting the Ronin kit here is a bit more costly. I'm not sure we have the correct 8.8s here as well, so that's just more cost in shipping and taxes.

You guys seen that full carbon bodied FD? That makes no sense. Maybe that dude wants a billet diff case :lol:

Narfle 06-16-23 01:50 AM

https://cimg4.ibsrv.net/gimg/www.rx7...3cd49f0d40.png
https://cimg5.ibsrv.net/gimg/www.rx7...694a8e4cb7.jpg

TeamRX8 06-16-23 02:48 AM

you can’t afford a Ronin kit, but came seeking a billet diff housing

you’re doing a better job than I ever could :dunno:

it has nothing to do with politics either, it’s here because this is where it applies
.

mr2peak 06-16-23 05:39 AM


Originally Posted by mr2peak (Post 12564209)
@Billj747 I live in Thailand, getting the Ronin kit here is a bit more costly. I'm not sure we have the correct 8.8s here as well, so that's just more cost in shipping and taxes.


Originally Posted by TeamRX8 (Post 12564337)
you can’t afford a Ronin kit, but came seeking a billet diff housing.

Never said I couldn't afford it. But it would be $4,500 by the time I had it in hand. So yeah, of course I'm exploring options.


Once upon a time I said "I wonder who makes covers for the wheel wells in the FD engine bay"? Now I make nice carbon (and carbon/kevlar) covers for the wheel wells in the FD engine bay. Sometimes asking and exploring options leads to more income or a better end product.


This is for you @TeamRX8 , I know your beliefs are important to you.“Be kind to one another, tenderhearted, forgiving one another, as God in Christ forgave you.”

Ephesians 4:32 ESV

Sgtblue 06-16-23 07:42 AM


Originally Posted by mr2peak (Post 12564343)
…..
Once upon a time I said "I wonder who makes covers for the wheel wells in the FD engine bay"? Now I make nice carbon (and carbon/kevlar) covers for the wheel wells in the FD engine bay. Sometimes asking and exploring options leads to more income or a better end product.


If this was a feeler for interest in a billet differential case you wanted to offer, maybe you should’ve just said so. Probably still wouldn’t have gone the way you wanted, but the thread would be mercifully shorter.

mr2peak 06-16-23 08:27 AM

lol it was just me asking if anyone has made one in the past. Sometimes you ask about things like this, and someone posts up a crazy build by some dude on Neptune with a bunch of really interesting details

SETaylor 06-16-23 03:11 PM


Originally Posted by Valkyrie (Post 12563998)
I am having problems with leaks, mostly.. which I think could be related to heat?

Don't quote me on this, but I believe that when the gear oil in the differential is overheated, it will expand and weep out of the vent on the differential and maybe the drain plug too. I think ptrhahn and smokey had issues like that where the fix was adding a differential cooler. Same story for transmission.

Valkyrie 06-16-23 06:25 PM


Originally Posted by SETaylor (Post 12564425)
Don't quote me on this, but I believe that when the gear oil in the differential is overheated, it will expand and weep out of the vent on the differential and maybe the drain plug too. I think ptrhahn and smokey had issues like that where the fix was adding a differential cooler. Same story for transmission.

Tranny pukes oil like a drunk college girl…

Billj747 06-18-23 09:47 AM


Originally Posted by mr2peak (Post 12564108)
Just checked out the MotoIQ article you wrote, "The OS Giken LSD has some of the smoothest operation of any aftermarket LSD we have tested with minimal to no noticeable ‘chattering’ side effects." Is this something that developed later on once you put more miles on the diff? Or did you change something else in clutch pack / spring setup that lead to more chatter?

No Wavetrac for the FD case, that's another solid argument for going 8.8

It's a 2 rotor on pump so I doubt I'll be breaking axels. Nothing else on this car is prepared for that level anyway.

That was written prior to Wavetrac being an option and relative to its clutch type competitors. My article explains how I reduced chatter further by deactivating plates and installing different preload and negative springs. There are some conditions that cause an occasional "pop" from the diff which is annoying.

I was talking to Wavetrac about making an application for the FD because it would probably be the best all-around option for the stock diff housing. My build quickly got out of hand so I went the 8.8 route.

You'll likely be fine with the stock axles and a girdle would be really good, cheap insurance. But then it still comes down to the lsd options.

It's relative. Mike is probably referring to a constant "chatter" like a KAAZ, but the osg will often have a "pop" or two when making very tight turns or accelerating moderately when making a turn, both of which were acceptable to me years ago but in a DD it's annoying and no longer acceptable.

Slides 06-19-23 04:07 AM

I'm surprised the OSG is that aggressive, I have a cusco and I actually want more pre-load in it, never had any dramas with low load chatter or binding, certainly no more than the factory diff. It's such a shame the factory torsen was cross gear type and not parallel like the truetrac, would have been strong enough then and had more internal resistance.

Billj747 06-19-23 06:50 AM


Originally Posted by Slides (Post 12564737)
I'm surprised the OSG is that aggressive, I have a cusco and I actually want more pre-load in it, never had any dramas with low load chatter or binding, certainly no more than the factory diff. It's such a shame the factory torsen was cross gear type and not parallel like the truetrac, would have been strong enough then and had more internal resistance.

Every application is different but for the most part, OSGs pretty much always have some sort of clunk/chatter. Is your Cusco in an FD? Why do you want more preload?

Billj747 06-19-23 08:58 AM

Repost

FD Wheel Covers In Carbon 05-21-24 06:15 PM

GTRs get all the good stuff...

Billet case to hold 8.8 diff and gears, bolts right into a GTR. Would be an amazing product for the FD.

https://cimg0.ibsrv.net/gimg/www.rx7...faa0e73503.png

Billj747 05-22-24 11:15 AM


Originally Posted by FD Wheel Covers In Carbon (Post 12603703)
GTRs get all the good stuff...

Billet case to hold 8.8 diff and gears, bolts right into a GTR. Would be an amazing product for the FD.

That setup is about $10K AUS ($6,700 USD) and includes DSS Pro Axles ($3K), an Eaton TrueTrac LSD ($675), and either a 3.5 or 4.1 ring & pinion ($200). That makes the aluminum housing under $2K which is pretty darn good.

I would need to look into it more, but a quick search shows IRS Ford 9" housings for $500-2,000. If they really are under $1K then that's hard to pass up on if you need a diff more capable than the Explorer 8.8's 1,000-1,500 limit. Especially since Grannas is offering a 9" subframe for the FD. If the 9" is closer to $2K, then the PRP aluminum one might be a decent option, especially for road racing; but then again, the Explorer 8.8 is probably more than enough for even 3 and 4 rotor road race cars.

FD Wheel Covers In Carbon 05-22-24 11:59 AM

That's a billet GTR diff case, that's made to hold the 8.8 internals. Bolt it in and go 8.8 upgrade, no welding of other mods.

That would be great for an FD.

Billj747 05-22-24 12:14 PM


Originally Posted by FD Wheel Covers In Carbon (Post 12603759)
That's a billet GTR diff case, that's made to hold the 8.8 internals. Bolt it in and go 8.8 upgrade, no welding of other mods.

That would be great for an FD.

Correct, it's an R200 housing was also used in the 280Z, 300ZX, S13, Datsun 510, etc... It would take similar modifications as the 8.8 to get the R200 to work, which isn't bad at all and far easier than trying to stuff a Ford 9" in there, which Grannas did do with their new fabricated subframe. But prior to that billet R200 being made, the Ford 8.8" diff is better and more available than the stock R200.

Stock FD < R200 < Ford 8.8" < Billet R200 < Ford 9"

FD Wheel Covers In Carbon 05-22-24 06:17 PM

I mean, I want a billet FD case that holds a ford 8.8, just like this R200 case with 8.8 internals.

Drop your FD diff, bolt up the billet case with 8.8 internals, go have fun. Keep the PPF, use braces, whatever you want. But in OEM style fitment.


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