Help w/ diff bushings: Ford 8.8 into RX7

[frijolee]

Greetings and Saluations,

Funny how car projects lead us to all ends of the internet isn't it? Short story... I work as a mechanical engineer in Southern California and drive a Chevy LS1 powered Mazda RX7 rocking Nissan 350z brakes.

I'm looking to upgrade my IRS to the excellent 31 spline 8.8 diff found in the explorers (what's one more manufacturer after all?) This is being done both to help my available gear ratios, add some strength and help prevent wheel hop.

The last point is what brought me here... Does anyone know of a vendor that sells a proven bushing replacement for the single front mount of the rear diff? I'd be looking for polyurethane or delrin or something harder than stock but not quite solid aluminum.

I've searched a variety of permutations of terms and thus far come up dry. Do folks just not screw with their diff mounts when used in truck applications?

Regards,
Joel Payne

 

[imp]

Greetings and Saluations,

Funny how car projects lead us to all ends of the internet isn't it? Short story... I work as a mechanical engineer in Southern California and drive a Chevy LS1 powered Mazda RX7 rocking Nissan 350z brakes.

I'm looking to upgrade my IRS to the excellent 31 spline 8.8 diff found in the explorers (what's one more manufacturer after all?) This is being done both to help my available gear ratios, add some strength and help prevent wheel hop.

The last point is what brought me here... Does anyone know of a vendor that sells a proven bushing replacement for the single front mount of the rear diff? I'd be looking for polyurethane or delrin or something harder than stock but not quite solid aluminum.

I've searched a variety of permutations of terms and thus far come up dry. Do folks just not screw with their diff mounts when used in truck applications?

Regards,
Joel Payne

I, too, am a degreed Engineer, and over the years have found that some of the BEST changes to equipment, I designed & fabricated myself. As an example, heavy-clutched early Ford Muscle (specifically, '67 Shelby GT-500) shredded away the thin nylon bushing Ford provided for the clutch pedal shaft to pivot in. I replaced wth a Torrington needle bearing, slick! imp

 

[BrooklynBay]

Welcome to this forum! Contact some of the vendors on this site. I'm sure that one of them will have what you're looking for.

 

[dw43935]

A Mazda RX-7 with a V8? That just sounds like alot of fun! Please post pics. I gotta see this.

 

[frijolee]

Welcome to this forum! Contact some of the vendors on this site. I'm sure that one of them will have what you're looking for.

Anyone in particular I should start with?

A Mazda RX-7 with a V8? That just sounds like alot of fun! Please post pics. I gotta see this.

It's a great conversion, here's a fews shots...

My build thread is a sticky at www.norotors.com if anyone is curious to know more. http://www.norotors.com/index.php?topic=1274.0

Anyone else care to chime in on my diff bushing question? This forum is laid out a biff differently from most I'm on so I'm still poking around blindly.

Thanks in advance,
Joel

 

[frijolee]

Explorer rear diff bushing question: 8.8 used in another application

Posted this in the newbie section as well...

>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Greetings and Saluations,

Short story... I work as a mechanical engineer in Southern California and drive a Chevy LS1 powered Mazda RX7 rocking Nissan 350z brakes.

I'm looking to upgrade my IRS to the excellent 31 spline 8.8 diff found in the explorers (what's one more manufacturer after all?) This is being done both to help my available gear ratios, add some strength and help prevent wheel hop.

The last point is what brought me here... Does anyone know of a vendor that sells a proven bushing replacement for the single front mount of the rear diff? I'd be looking for polyurethane or delrin or something harder than stock but not quite solid aluminum.

I've searched a variety of permutations of terms and thus far come up dry. Do folks just not screw with their diff mounts when used in truck applications?

Regards,
Joel Payne

 

[imp]

WOW! Kind of redundant now to ask if anybody cares to see a '48 Lincoln V-12 in a '52 Ford Sedan, ain't it? imp

 

[frijolee]

Merry Christmas y'all.

 

[IZwack]

Threads merged (same topic) and moved to "Transmissions, Transfer Cases, & Differentials".

 

[drdoom]

You might try energysuspension.com

 

[joecrna]

That RX7 should be wicked fast and handle well too. Is it licensed for the street? If so, please lend me some ideas as how to accomplish a simular feat. Can't stand CA smog regs.

 

[CDW6212R]

Find as much as you can about the stock bushings or parts from elsewhere. Then search to connect that with Energy Suspension for the poly bushings. The Delrin used to be from Global West IIRC from 25 years ago. I'd contact them to see if they could help in putting together a bushing. Good luck,

 

[IZwack]

You know... delrin/acetal and other plastics really isnt that hard to turn (small OD). If you have a good (floor standing?) drill press, you could probably turn a few bushings on your own (like a lathe).

 

[CDW6212R]

Yes, Global West was very helpful back then, they would make anything you needed from Delrin. I had them make UCA bushings for my 72 Ford, an application that no performance part were available for. That was 25 years ago though, times change and businesses get sold etc. Give them a call and see how things are now. Regards,

 

[peanuttbutterman]

best rat rod ever built

 

[joecrna]

The mustang guys put the Explorer diff in for drag racing and other performance applications. What do they use?

 

[dw43935]

VERY impressive! I've always liked the RX-7 & have seen alot of nice ones out there, but I gotta tell you that this one takes the cake!

 

[frijolee]

Thanks for the leads and the compliments y'all. Apparently some of the cobra guys melt delrin bushings so I suspect it'll end up with an aluminum front after all. At least the subframe has separate isolation to the chassis.

For what it's worth RX7's make great swap candiates in part because of the geometry of the rotaries they came with. An eccentric shaft in a wankle is right in the middle of the motor vs. the driveshaft in a piston motor usually being down low. As such, the transmission tunnels in RX7's are unusually tall and that makes it easier to put an engine with a big bell housing close to the firewall.

Motor added about 60 lbs and I'm still 50/50 weight ratio. I like to tell folks that I tripled my horsepower, quadrupled my displacement, but my gas mileage still went up vs. the motor that came out. Yes, it's a street car. I even have A/C.

Lots of crazy swappers at www.norotors.com if anyone wants to check out the scene.

Thanks again,
Joel