BoxsterLS376 introduction - LS3 conversion :)

[Stroked & Blown]

John,
I've been following this thread and just noticed some GT3 CUP axles for sale on rennlist: 996/997 GT3 Cup Motorsports Axles - Rennlist Discussion Forums

No idea what it would take to use these, but figured I'd pass it along.

[BoxsterLS376]

Ok so I did a bit more research today and one of my buddies at work pointed out something I had not thought of, the ABS ring. DOH>

So to answer all the 911 axle thoughts, no, they will not work. Mainly due to the ABS ring being in the wrong spot. If you don't care about ABS it may work, but i'll let you find that out.

So I tore apart one of my factory axles today and cleaned it up to see if I could use it as a 930 stub. For the record the CV that connects to the transmission is a 108mm joint, same as on the old 930 Turbos which is perfect because those are the joints I want to upgrade to!

The outer joint however is like 104mm and now I have to figure out a way to adapt a 108mm CV to it. I just went and looked and I think it would have to stay the same size until the end then have it flare out to 108mm in order to clear the wheel hubs. Next problem is a clearance issue with the sway bar link because the 930 joint would be so much further inboard then the stock joint. UGH.

I have a few ideas... The first and most expensive would be to have someone 3D scan the stub end, modify it accordingly then CNC it out~ That just sounds expensive. The second idea which my boss came up with is to slightly machine down the stub, then press a something like a 5mm collar that is 1/2" long onto the existing stub so it can be drilled and tapped out to accept 10mm axle bolts.

Once we have the stub in place the rest should be easy, just measuring and building the rest of the axle. heh. should be easy!

Here is what I'm working with, the 986 outer stub and a 930 cv joint cover:

[Smallblock454]

Hello John,

i have a stupid question. The axle itself is fixed with a circlip at the transmission side and at the outer side you can also disconnect it (did it when changing my axle boots). Isn't it maybe possible just to change the axle itself and take the inner and outer parts as they are?

Regards, Markus

[BoxsterLS376]

Originally Posted by Smallblock454

Hello John,

i have a stupid question. The axle itself is fixed with a circlip at the transmission side and at the outer side you can also disconnect it (did it when changing my axle boots). Isn't it maybe possible just to change the axle itself and take the inner and outer parts as they are?

Regards, Markus

Part of the problem is the CV joint Markus, the stock joints are wearing out very fast, like within 3,000 miles the joints are worn enough to cause vibration while accelerating.

I am still in the discovery phase so if I can figure out a way to build a good axle setup then great, if not i'll just sell it as-is and let the next guy worry about it.

[Smallblock454]

Thanks for the info, John.

Well, i have to admit that i have no idea how to solve that in an easy way.

Regards, Markus

[JRL]

Hey JJ did Steve have a good solution for your axle problems.

Did you get the video links and pictures I sent you?

[BoxsterLS376]

Originally Posted by JRL

Hey JJ did Steve have a good solution for your axle problems.

Did you get the video links and pictures I sent you?

Hey Randy,

Yes I did, very cool!

I spoke with Steve and while I'm sure what he does will improve the situation, I'm not sure i'll be 100% happy with it. Basically supplying factory axles which he would then be "race prepping" the outer CV joint. That is all he wants to do which is basically changing to a chromoly cage and put in "good" axle grease. Not sure that is going to solve my problems, but rather buy a bit more time.

A big part of my concern is the wear on the outer CV housing as this is causing me to wear out the axles in about 3,000 miles or less. Steve basically said I could expect to get 3x more life out of them which is roughly 9,000 miles, then I have to find a new set of factory axles, rinse and repeat.

I am going to talk to fabrication shop near by and throw some ideas at them to see if I can come up with a better solution. By better I mean longer lasting, stronger and easily replaceable or able to be rebuilt by me rather then having to send them back off to Colorado or wherever.

I am also going to talk with them about producing V6/V8 conversion parts. I've been looking around lately and am thinking that the newer 3.6L V6 from the 2012+ Camaro could be a good replacement for bad 986 motors. They make 323 HP, are pretty compact so hopefully the conversion could be done without any cutting of the existing structure and from what I can see used motors are fairly cheap and plentiful. Just be a matter of the full integration with wiring etc. which means you likely need a throttle pedal etc. and I don't think Chevy makes a plug and play type setup for the V6 motors like they do the V8s. I'll start another thread on that once I gather a bit more info.

Thanks
J

[FauxDiablo]

Originally Posted by BoxsterLS376

Hey Randy,

Yes I did, very cool!

I spoke with Steve and while I'm sure what he does will improve the situation, I'm not sure i'll be 100% happy with it. Basically supplying factory axles which he would then be "race prepping" the outer CV joint. That is all he wants to do which is basically changing to a chromoly cage and put in "good" axle grease. Not sure that is going to solve my problems, but rather buy a bit more time.

A big part of my concern is the wear on the outer CV housing as this is causing me to wear out the axles in about 3,000 miles or less. Steve basically said I could expect to get 3x more life out of them which is roughly 9,000 miles, then I have to find a new set of factory axles, rinse and repeat.

I am going to talk to fabrication shop near by and throw some ideas at them to see if I can come up with a better solution. By better I mean longer lasting, stronger and easily replaceable or able to be rebuilt by me rather then having to send them back off to Colorado or wherever.

I am also going to talk with them about producing V6/V8 conversion parts. I've been looking around lately and am thinking that the newer 3.6L V6 from the 2012+ Camaro could be a good replacement for bad 986 motors. They make 323 HP, are pretty compact so hopefully the conversion could be done without any cutting of the existing structure and from what I can see used motors are fairly cheap and plentiful. Just be a matter of the full integration with wiring etc. which means you likely need a throttle pedal etc. and I don't think Chevy makes a plug and play type setup for the V6 motors like they do the V8s. I'll start another thread on that once I gather a bit more info.

Thanks
J

Not even going to go back and look at what all this axle talk is about.

I know a couple things though... (1) Never have a place in Kansas design custom axles for you. (2) If you need any kind of custom axle designed, especially Porsche-based CV axles, you go straight to a company called The Driveshaft Shop, and you don't look back.

The Driveshaft Shop | Home page

[BoxsterLS376]

Originally Posted by FauxDiablo

Not even going to go back and look at what all this axle talk is about.

I know a couple things though... (1) Never have a place in Kansas design custom axles for you. (2) If you need any kind of custom axle designed, especially Porsche-based CV axles, you go straight to a company called The Driveshaft Shop, and you don't look back.

The Driveshaft Shop | Home page

Well you should read back a bit, the drive shaft shop is great but want close to $4,000 for a pair of axles and I am not spending that much more on this car. I will chew up 40 $100 axles before i do.

[Ben006]

A v6 swap would definitely be a good idea!
Lighter, smaller, sounds good (to me at least), plenty of power, and probably cheaper to get!
And you'll get the Cv axle more aligned since the engine will be shorter!

[BoxsterLS376]

Originally Posted by Ben006

A v6 swap would definitely be a good idea!
Lighter, smaller, sounds good (to me at least), plenty of power, and probably cheaper to get!
And you'll get the Cv axle more aligned since the engine will be shorter!

Thanks for the feedback Ben,

Hopefully the axles wouldn't be an issue! It does look like an interesting opportunity as it "should" be an easier install etc. Right now Chevy does not seem to be offering a "crate" version but used ones seems to be available for around $2K~

Plus you could still get crazy if you wanted as it looks like the mounting for the V6/V8 would be very similar so if you wanted to upgrade later that could be an option... Of course I found a company out there who is making a twin turbo kit for the Chevy V6 and making 575HP so that could be an option too!

I'm definitely spinning the wheels on this one so any other feedback would be appreciated.

Thanks!
J

[BoxsterLS376]

Well I went over and talked with my engineering/CNC guy and looks like my initial "economic" thoughts are pretty much out the window I'm about to give up on this, I don't know if there is going to be any inexpensive way to completely solve this.

Does anyone know what size the outer CV joint are on later model Boxsters/Caymans? Mine is about 104mm and I need to be able to fit a 108mm in it.
Would later model rear suspensions/wheel carriers stuff bolt up to an earlier car?

Does anyone have a low mileage set of factory S axles laying around? Mine are shot but may be able to get some 60K~ axles, if anyone can do better then that get in touch.

[JEhunter]

John - I did a little research on the GM V6 (Camaro) motor after our call today.

2012-2015 Camaro V6. 'LFX' 3.6L aluminum motor/aluminum heads DOHC. It makes 323 HP @ 7200 rpm and 278 Lb-ft @ 4800 rpm. I couldn't find the weight on the motor but my guess is that it's lighter than the stock Boxster 3.2L.

I'll see if I can find some dimensions on the V8 so we can compare them to the LS. This could be pretty sweet build

I found the weight. GM claims 345 Lbs and Porsche show the boxster motor weight at 399 lbs. So, the LFX looks to be about 54 pounds less...

[BoxsterLS376]

I agree, I think it would be a great replacement option! Finally got a call back from the V8 Miata guys and they are pretty tied up with other projects until later this year. I was told they have already come up with an adapter plate setup which is there own custom doing and not a Kennedy Engineering piece, although that is about all I got from them. I've got a message in to their Engineer who is up in Tennessee so hopefully he will call me back.

I also put a message out to Kennedy Engineering but no word back yet. My fabricator could definitely come up with a good mounting system but an adapter plate and clutch setup may be asking a bit much.

Next step I think is to figure out some dimensions as I'm pretty sure there will be some height clearance issues. See how bad we are off and figure out options to correct it. Might be as easy as modifying the engine cover or may take a redesign of the intake manifold.

Between the adapter plate and clearance I think those are the biggest issues. A few other variables to work out with regards to the fuel system etc. but nothing major I think.

I think it can be done. Let's figure it out
J

[BoxsterLS376]

Looks like Kennedy Engineering has an adapter plate setup and clutch available, but you need a special tool to modify the transmission apparently which they have available to rent so it is do-able.

I'll try and stop by my fabricator guy and see what it may take to come up with a mounting system for it...

[JEhunter]

John, I noticed in another post that you talked about doing the LFX swap in a non 'S' boxster. I like that idea because there are so many more non 'S' cars out there and the prices are getting super cheap. Other than the 6 speed tranny, why would the 'S' car be better for the LFX? In my opinion, you're going to upgrade the brakes anyway and then a suspension upgrade is probably a close second in any car...

[JRL]

Originally Posted by JEhunter

John, I noticed in another post that you talked about doing the LFX swap in a non 'S' boxster. I like that idea because there are so many more non 'S' cars out there and the prices are getting super cheap. Other than the 6 speed tranny, why would the 'S' car be better for the LFX? In my opinion, you're going to upgrade the brakes anyway and then a suspension upgrade is probably a close second in any car...

You would also need to upgrade the cooling but I see where you are coming from. Renegade actually used a non-S car for their prototype.

[BoxsterLS376]

At this point I don't think i'll be pursuing any more Boxster projects, i'm already in the hole to deep on this one. Unfortunately I don't have an endless bag of money to try new things, and personally I have no real interest in a "V6" boxster, just thought it would be a good option for people to keep these cars going.

V8 car is going to be put onto Ebay soon to hopefully find someone who will enjoy it as much as I have. Hopefully they will have the time and money to finish off the gearbox/drivetrain then the car will be 100% awesomeness.

While i've had my fair share of cars I know i'm not the most experienced out there, but I've put almost 5000 miles on the V8 car and must say, it is the best car I have ever owned.

I appreciate everyone following along on my crazy little adventure. Hopefully I've been able to help some of you out along the way, either with your projects, or your decision to take it on at all This is the end of the road for this project... I'm tapped out.


J

[shockandawe]

Thanks John for everything I learned a lot from your build. I was gonna do the same swap to, but since you had some troubles and the cost I decided sell boxster. I have now purchased 996 which is cheaper to do , has less problems and can handle the power.Again your post gave me a road map on how the swap is done. good luck.

[BoxsterLS376]

Originally Posted by shockandawe

Thanks John for everything I learned a lot from your build. I was gonna do the same swap to, but since you had some troubles and the cost I decided sell boxster. I have now purchased 996 which is cheaper to do , has less problems and can handle the power.Again your post gave me a road map on how the swap is done. good luck.

You are quite welcome. Unfortunately this is the exact reason I have lost interest in pursuing further modifications/kits for the Boxster. Reality is that spending that much money on a Boxster just does not make much financial sense for most people as they are not/do not hold their value like a 911 and never will.

Even though IMHO the Boxster/Cayman is a much better platform, now that Porsche has started to wise up and offer some engines with a reasonable amount of power in them the V8 swaps make less and less sense. Although there is no replacing that V8 sound, which reminds me I need to take off those stupid mufflers, the car is so much more fun to drive when it is loud as hell

I imagine a 911 swap would be easier, hopefully I can sell the V8 Boxster and get to figuring out the next project soon. Not sure if i'll do another swap or just try and build a fast fun car with a 996TT, or a Cayman set up for 1/2 mile drag racing? Who knows~