997.1 C4S RWD conversion

[Maruscmn]

Long story short my 07 C4S has gone through 3 sets of front inner CV boots in 40k miles. Why this is occurring is what I plan to find out.

First as little background. I purchased this back in 2018 from a private seller in Jacksonville FL. The car was first ordered by a Brumos Porsche family member to their specifications (C4S black with sand interior, carbon package and little else) When it arrived to Brumos they installed a factory aerokit along with H&R springs.

The second owner added the F77 engine package from Champion Motorsport (Werks air box/plenium, Tubi exhaust headers, Tubi mufflers, GIAC software). I then purchased the vehicle.

Now the 997.1 C4/S AWD system is purely mechanical and can be removed. Many 996 owners have done this. Since this is a completely reversible mod, I plan on converting my car to a RWD while I analyze the root cause of my tearing CV boots at my own pace. This will also give me the opportunity to learn a new skill (replacing CV boots)

Parts ordered:

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First order of business will be to procure a 340 ft/lb torque wrench for the Axel nuts....

[Tom]

Interesting project. Looking forward to updates.

Harbor Freight sells a 600 ft lb Icon torque wrench for $400....

And here's one on Amazon for $169...

https://www.amazon.com/SuZhi-1-Inch-Dri ... 77858&th=1

[Maruscmn]

I never pass up the opportunity to purchase new tools. Technically it save me money…

I may stop by the university and talk to the mech-e department. They have quite the selection of tools also.

Mike

[Maruscmn]

Decided to buy a underhoist support stand as Ive been meaning to for a long time and just never pulled the trigger. I had to find one that fit under my maxjax (48” lift). With that being done and finding a torque wrench i could borrow when I need it, i started the project.

Removed the under panels.

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As in all projects I discovered a potential issue..

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Yep thats my transmission mount insert. Well part of it anyways. That sent me to Function First for their aftermarket products. I ended up going with their Orange insert (softest) to get as close to OEM as possible. Fantastic customer service also. So while I wait for the insert to come in I’ll start disassembling while at the same time clean up my weeping RMS.

[Tom]

Looking forward to following along with this!! My 992 has bumper to bumper under panels too. It never dawned on my until seeing that picture how nice and clean they keep the under-carriage. Looks like a brand new car under there! Curious why you opted for an aftermarket transmission mount?

[Maruscmn]

Honestly i don't have a compelling reason besides wanting to see for myself if I notice a difference in NVH or shifting behavior. The cost is low enough that if I don’t find it to my liking I can easily switch it out back to OE. I was surprised that the OE version was done after 39K miles.

I did find some chip and seal rocks on top of the under panels but I agree it does look nice and clean! I’ll get my steamer out and scrub the rest at my leisure!

Mike
OPS

[Maruscmn]

Well that was actually one of the more straightforward projects Ive had.

Remove gas tank straps and the V-brace to gain easy access to the inner CV boot.

Remove the inner CV boot from the Diff:

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I then went to the back and braced the transmission: Remove the bracket - watch your transmission mount insert crumble to the floor. Sweet.

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Remove the 3 bolts on the guibo.

Now I went to the front and removed the nuts and then the long studs holding the front diff. It needs to be braced to do this as it will now be ready to lowered after the next step.

Remove the center bracket but first remove the 15mm bolt on top and set free the coolant lines.

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Now with the help with a friend lower the whole unit out (sans axles - they are still held in by the axel nut and pressure)

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Next use a punch to smack out the axles. A couple good whacks did the job.

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Ended up being about 78lbs.

Time to clean up the front (Those are the studs that held up the diff)

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Front end sans diff:

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To do list:

Clean up the back. Put in transmission mount insert. Torque axle nuts to 340ft. lbs. And figure out how to protect this in the meantime.

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Overall fun job!

[Tom]

Awesome work! Like so many things on the internet, you make it look so easy and clean. Why no greasy mess at the end of the CV joints? -- must be new-fangled parts I'd be happy to design and 3D-Print a bolt-on cover for the flex joint stub if helpful -- would just need some dimensions, etc. To a hammer, everything looks like a nail. To a 3D-printing guy....

[Maruscmn]

Tom, you read my mind! My friend and I were saying the exact thing. "this looks like something that needs to be 3d printed". Let me study it and get back to you. I have to figure out which design would work the best - a complete cover that bolts onto the guibo through the m10x1.5 threads (with nylon bolts) or something smaller.. preventing oxidation can accomplished with some grease and a cap. Sorry just thinking out loud here.

As for the grease it was already flung all over when they ripped in the last 3K miles :-/ everything else (diff back) is covered by the body panels. I will clean up the back where my RMS is seeping...

Mike

[Tom]

Does it spin? That would push me toward the bolt-on version, unless that shaft end has a threaded hole?