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Sorry for going off topic, but the PDG GTM is pretty cool to watch videos of in action. Crash, will there be any changes to the body of the Gen II for aero?
We will be exploring some wing options for sure, and I believe that the MONSTER front canards are going on the car, but other than that I don't think so.
 

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What about getting rid of air pressure that builds up in the wheel wells and front nose? I see a good amount of pressure building up in the nose at high speeds.
 

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Richard is due to send me some pictures, but hasn't yet.

One of the times I was talking with him, he said he was bending up the pieces for louvers, and I would assume these are for the front fenders and the rear deck, as was on the other body, but I don't really know for sure. We also discussed the rear of the car and how to get more air flow through the engine compartment. The Gen II design should allow for more to be cut out back there, but we'll see what the final product looks like when Richard sends me, or posts some pics. :)
 

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And BTW, it is my opinion that one would HAVE to have either independently controlled motors or a diff in order to allow the car to turn with front powered wheels.
This isn't quite true. If you want to maximize turning and use torque biasing and all that jazz, sure...But you don't need independent controllers to have a diff. action.

This isn't directed at anyone in particular, but there is a lot of misinformation about motors in this thread. I've done A LOT of work on our motor and control system for our FH car this year and can probably tell you whatever you want to know. If you have a specific question, ask it, and I'll answer to the best of my knowledge.

-Cole
 

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What about the engine....any upgrade there?
Nope. They pulled the bottom end apart to check for oil starvation damage since the main oil line was knocked off and the car was driven for about half a lap that way, but apparently the report is "no problems" in the bottom end, so all will be the same for this year. Just under 400 RWHP.
 

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Discussion Starter #47
OK let us explore the use of a Panamera drive-train. After altering the GTM’s rear frame section to accept the Panamera’s engine, transmission and front differential and after altering the GTM’s front to receive the Panamera’s rear differential. What needs to be done to address the fact that I currently have 1 forward gear and 7 reverse.
 

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OK let us explore the use of a Panamera drive-train. After altering the GTM’s rear frame section to accept the Panamera’s engine, transmission and front differential and after altering the GTM’s front to receive the Panamera’s rear differential. What needs to be done to address the fact that I currently have 1 forward gear and 7 reverse.
I haven't looked at the specifics of the Panamera setup, but barring the fact that you will likely find it near impossible to find one of these drivetrains since, it is my understanding, these are no longer being produced, and a very limited number of them were actually sold, it sounds like the engine is in front, then the transmission behind, and then a drive shaft goes up to the front axle in the stock setup? If that's the case, then you would just move what is in the front of the car to the rear. This would get you a mid engined car with the gears moving in the right direction. Difference would be that the rear drive shaft would get very short and the front one would get long. Now, in this configuration, assuming all my assumptions are correct, there would STILL be a MAJOR issue of fitting all this into the rear of a GTM. You would have to stack both the trans AND a rear axle behind the engine, and there just isn't anywhere near enough space to do this.

I would say that the only REASONABLE way to get you what you want, without breaking the bank, is to use a STANDARD transmission, but setup to rotate backwards, put a transfer case mid ship, and run drive shafts to the front and rear axles. I'd probably use something like a Toyota 4 Runner front diff housing front and rear, and then build the rest so it isn't absurdly heavy.
This would package well because you could tuck the rear diff housing right up against the engine, put the transmission in the tunnel area, and many of the parts would be "off the shelf". You might even be able to accompolish the reversal of the rotation through using an extra gear in a slightly modified transfer case. This would bring the cost and complexity down considerably.

Now weight? FAGET ABOUT IT!! This thing WILL be heavy. Although not nearly as much as the electric option IMHO.
 

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Did some digging and found that Porsche is still selling this model, although at 20,000 units world wide, it's not a big seller, and I doubt you will be finding a bunch in the yards any time soon.

Anyway, I have not been able to locate a picture or drawing of the drivetrain configuration. If anyone has a link or picture they can post, that would be great. The PDK is an AWESOME transmission. If I had my choice of race transaxles and money was not a factor, then a PDK dual clutch is what I would have. A little on the Rosanne Barr side of things, but I race endurance, and the buttery smooth, efficient paddle shifting ability would be worth the weight penalty IMHO. Very nice stuff.

I searched previously and found that the cheapest way to acquire this type of trans would probably be through a VW unit. I believe that there was talk of the system being only a couple thousand dollar upgrade on something like the Golf or Jetta IIRC. Anyway, if you are serious about this, that might be the cheaper way to acquire this technology.

Computers to control everything will be another matter all together though. :(

BTW- I DO realize that Porsche and VW are one company, and for the record, again IIRC from my previous searches, Getrag is the actual manufacturer of the PDK and it's variants. You may want to search under that name as well.
 

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Crash, they sold just over 22,000 Panameras in its first year of production, its most popular market being the US. So I don't see how this would be a hard platform to find parts for. It would be pricey, but all you'd have to do is go and talk to a Porsche dealer. Also, Porsche put a lot of time into the Panamera in order to make it a first on many levels. I don't see this car disappearing from Porsche's line up any time soon. Just look into their debut of the car, they made it pretty clear how important this car is to the company.

What I liked about the Panamera setup, which is probably similar to an AWD setup in most Porsches, is that it would be relatively easy to make an AWD GTM off of it. Due to flipping the engine around, the driveshaft would actually be pretty short. The rear axle would run through the oil pan of the engine and the rear driveshaft wouldn't be too long. This eliminates the weird geometry that the rear axles would be faced with if using a regular transaxle. In my opinion, the best way to make an AWD GTM possible would be to go through Porsche, VW, Getrag. You're talking the best in the business for quality car parts with performance in mind. This also steers clear of having an entire custom system made. The only parts that would need to be made for the car are the driveshaft, the axles and a new gear set for the tranny. If you were to talk to Getrag, they probably could send you the tranny with the gears flipped around for a small fee. Then all you'd have to do is the driveshaft and the axles, which would have to be custom made no matter what AWD system is used.

This would be pricey, but it also would be one of the nicest GTMs made.

Which brings me back to a question that the OP has yet to answer. Is there a budget for this build, and if so, how much? That determines a lot of the how and which parts of the build. Without knowing your budget, any advice given to you from here on out is theoretical discussion. No matter how you cut it, you're looking at stuffing a bunch of parts into a car not designed for them, so the price of this mod is going to be a lot. In the past, several have discussed using Subaru parts, which also isn't a bad idea.

As for pics of the Panamera drivetrain, here you go. This would be the rear axle on the GTM.

This would be the front.

And this is how the engine bay would look.


Not exactly impossible to do on a GTM, but it does put the engine at the very rear of the car. The only way around this, would be to have a company make a transfer case that worked off of a transaxle setup. It would make the transaxle more complex, by having a driveshaft come off of the rear axle. That possibly would be the easiest way to pull this off. You wouldn't have to move the engine around, but it still would cost a lot of money.

I just thought of this idea, and I'd like to know what you think Crash. Use a regular LS engine and a Porsche transaxle. Off of one of the sides of the transaxle would be a transfer case, right where the axle goes. The driveshaft would work off of the axle, inside of the transaxle. Essentially making the transaxle and transfer case one piece. The driveshaft would be long, run along the bottom of the engine, but the plus side would be simplicity. Nothing in the engine bay would really need to be altered that much, preserving the weight distribution while keeping the added weight of the AWD system as low as possible. With the front axle, diff, transfer case and driveshaft, I see this as roughly 300 lbs tops. Not bad for making the insane possible. As far as I know, no one makes this type of transaxle / transfer case. I don't know of any mid-rear engine, AWD vehicles.
 

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Um...OK. Let's compare the number of Panamera vehicles sold by Porsche and those sold by Sabaru in the US.

Yes Porsche sold 22,000+ Panameras in the US, but Sabaru sold a combined 18,660 Foresters, Imprezas, Legacys, and Outbacks...in the month of January of 2011!!

At that pace, they will have sold about 224,000 vehicles this year!

And Sabaru is a relatively niche producer.

For instance, in May of 08 it is reported that GM sold 272,363 vehicles. That's for ONE MONTH.

Extrapolating out, that's 3,268,356 vehicles a year for GM.

Now, hopefully you can see where I was coming from when I said that you aren't likely to find a Panamera in a yard anytime soon. The sales numbers will neccessarily restrict how many end up totaled, and then because of their market value, it is HIGHLY unlikely that they would not be rebuilt. If there were a handful that couldn't be repaired and resold, then it is probable that it would end up in a "specialty yard" and once again be virtually unobtainable unless you were "in the business".

Bottom line, don't be thinking you will just go to a local junk yard and find this stuff cause it ain't gonna happen! ;)
 

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Crash, I never said to look in a junk yard for a trashed Porsche. I was talking about getting the parts for the vehicle, not exactly where he would find them. Yes, obviously you'd be more likely to find a trashed Subi in a yard.

Now, what do you think about the rest of that post. :)
 

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OK so like I said, the Panamera setup would NOT work because you would have to stack the rear axle behind an already insanely long transmission.

Plus side is a torque biasing center diff is already part of the setup. :)

Yeah, you could add a front output to the side of a transaxle, but the packaging of the standard transmission along with a "special" transfer case would work much better because not only will the transmission fit down the tunnel, but there will be plenty of room in the rear for the IRS, diff housing, etc. Not to mention the fact that the drive shaft lengths will be roughly split equal fron and rear. Long drive shaft lengths get to be an issue sometimes, particularly with higher HP/TQ applications. ;)
 

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Crash, I never said to look in a junk yard for a trashed Porsche. I was talking about getting the parts for the vehicle, not exactly where he would find them. Yes, obviously you'd be more likely to find a trashed Subi in a yard.

Now, what do you think about the rest of that post. :)
OK, so you are suggesting going to the parts counter and ordering all the components new!? OUCH!!!

May as well buy a Panamera whole. I'm pretty sure one would end up paying about 75% of a complete cars value if doing that. Maybe more than 100% if looking at the used car market!

As you said, the budget defines everything, but what in life ISN'T defined by the budget? :)
 

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I am not sure how they are biasing / distributing the power on the Porsche. The GT-R as an example (I think that is the drivetrain shown in the original post) does up to 50% to the front wheels and up to 100% to the rear wheels. The rear drivetrain is more capable of handling power. Moving the front drivetrain to the rear, like what is being considered for a GTM config, would put weaker components where you might want to have most of your power. Even the pictures of the Panamera look like the front axles are smaller than the rear...that might also translate to less capable gears, etc.
 

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So you are looking at flipping the engine / tranny around and then down the tunnel much like a front engine vehicle would be set up. Do you have a platform in mind to work off of? Subi perhaps? What would be your standard transmission? a TKO? A transfer case would be pretty easy to design with a TKO, as the rear half of the tranny is bolted on. It could be designed to have 2 driveshaft outputs.
 

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Well, one of the benefits to my idea is that, if indeed the reversal of rotation is accompolished in the transfer case portion of the setup, then ANY regular OEM engine and trans could be used. This could make creating a AWD GTM on par, cost wise, with some of the higher end RWD GTMs. Only custom components besides the very simple transfer case needed would be drive shafts and half shafts. Off the shelf 930 CVs all around, the adaptors that I already make in front and rear, Toyota diff houings or another that has the 930 CV bolt pattern, and BAM!! AWD GTM!:evil:
 

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Sweet. So where is this magical, universal transfer case? How are the designs coming?
 

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OK, upon further churning of this through my brain, there may also be some modifications to the front uprights required, and the addition of a center "diff" would probably be advisable also. Those run about $400 for a simple friction type like is used in the Jeep transfer cases for street use. Now remember, all these components are mechanical and this would kind of end up being an "old school" deal with no computer controls.
 

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Sweet. So where is this magical, universal transfer case? How are the designs coming?
As I said, all things are only as far away as the size of your wallet! ;)

The GTMs center console does make it particularly attractive to this idea though.
 
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