04-22-2020, 11:59 AM | #1 |
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Crazy, impossible future project idea?
I'm still smitten by this. Thanks JST.
I wonder if I could buy an ok-ish SL600, do a 6MT conversion, and do the Zonda sound upgrade. That could be a cool project. How to make a MB sound like a Zonda A 6MT SL600 That MT conversion seems to involve sourcing a 928 GTS 6-speed. The 6MT conversion would be the most difficult if even possible as a DIY project. |
04-22-2020, 01:04 PM | #2 | |
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But, yeah, that would be cool. And you have the garage for it. You could even do a YouTube vid and maybe pay for the project. |
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04-22-2020, 01:27 PM | #3 | |
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I don't know if that transmission will be cheaper, but it might be more accessible. 2007 is not that new either. But I do have the garage for a cool project, that car has always been special to me, and I think it would be a goo dad/boys project and maybe even something cool to put in college/job applications for them. Looks like half-decent SL600's can be had for $15-20k, so my wife did not tell me to go pound sand right off the bat. Had not even thought of the youtube part. My youngest wants to make a video channel (mostly to post video game exploits). |
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04-22-2020, 04:25 PM | #4 |
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So, your biggest hurdle in this project is likely to be passing an OBDII scan. I don't know for a fact that this applies to MBs, but I know that OBDII BMWs in the '90s would not pass emissions with auto to manual conversions without convincing the chassis that it was supposed to be manual. (Not that hard, but the MB is a lot more complex and has a lot less support.)
If you can put historic tags on, or use an OBDI car, you bypass that problem. I actually don't think that the physical manual conversion is going to be *that* difficult. It's just that you need access to a machinist who can make you a custom bellhousing. That's probably a better route than trying to source an extremely rare and probably expensive transmission. R129s were sold with three pedals from the factory, so you can source the pedal box and hydraulics. (It's worth noting that in the linked thread, people point out that it's actually highly unlikely that it was a 928 transmission used and speculate that it was probably a BMW unit.) Hell, it's likely that the V8 and the V12 share bellhousings, so there might even be an off the shelf adapter out there.
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04-22-2020, 05:30 PM | #5 | |
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How much of that is transferable to the V12 is a good question. The max continuous torque figure for that Getrag (550Nm) is below the torque peak of the M120 V12 (580Nm), but not by much... https://www.theslshop.com/parts-shop...l-gearbox.html |
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04-23-2020, 07:50 AM | #6 | |
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Not worried about designing custom parts or having them machined. That's what I do for a living and I know dozens of places that can make it. It may get expensive, but that's another issue along with getting it all to fit in the space there is. Is the OBDI/II thing needed for the car to work, or is it an emissions-related thing in order to get plates? I assume the latter. |
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04-23-2020, 07:55 AM | #7 | |
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04-23-2020, 08:49 PM | #8 | |
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but when you add in the rest of the fabrication and parts required (that appears to be a complete kit), I bet that rolling your own doesn't save much, if anything. Of course, the question is whether or not the V12 is compatible with the same transmissions. I'm not concerned about the power rating.
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04-23-2020, 08:50 PM | #9 | |
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04-23-2020, 09:17 PM | #10 |
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That may be true. If that $15k-ish get you a direct bolt-on, there is something to be said for that. But then, where's the fun?
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