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Discussion Starter #1
So after I scattered the internals of the 5speed in my Cayman all over the road, I swapped in a strengthened 6speed out of an 986 Boxster S. Love the box, however it's final drive is quite a bit taller than either the 5 speed or 6 speed Asin's that came in the 987. So the computer simply won't engage the cruse control in 6th. It's fine in every other gear, but in 6th the computer sees the ratio as out of range and won't set or hold a speed.

I figured it certainly couldn't hurt to consult the hive mind and find out if anyone might have run into this issue, or might have a solution.


Also, because first post, obligatory picture.:
269298
 

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Someone with a PIWIS could tell the DME that the car is a 6 speed.
Unfortunantly we did that in the original install. The problem, or as it was explained to me, is that because we used the stock 3.444 ring and pinion for the g86. That puts its top gear drive ratio at 2.89 vs the 3.18 top gear drive ratio of the g87. So the computer is seeing that the engine is spinning slower for the speed than is possible for any gear, and faults. (Both of the g87 6speeds use a 3.875 final drive with a .822 double OD for top gear.)
 

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Hmm, interesting problem. I think whether it can be solved will depend on where that cruise control programming lives. If it's in the ECU, a custom flash may be able to fix it. If it's in the cruise control module (more likely, I would guess) you might be out of luck.

It might be worth contacting Softronic or one of the other flash vendors to see if they have encountered this before.
 

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Hmm, interesting problem. I think whether it can be solved will depend on where that cruise control programming lives. If it's in the ECU, a custom flash may be able to fix it. If it's in the cruise control module (more likely, I would guess) you might be out of luck.

It might be worth contacting Softronic or one of the other flash vendors to see if they have encountered this before.
That is actually a really fantasitc idea. I shot them a message, I doubt I will hear anything back before tuesday, but we will see what they have to say on the matter.
 

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or maybe a cruise module from a 987-S ... if Scott says that's what the issue is.

now that I think of it, lemme look up part numbers to see if there are model differences ...

UPDATE - the only thing related to 'cruise' in the catalog was the cruise control switch ... unless that module has a name that didn't translate well I'm guessing that functionality lives in the ECU.

Scott Slaussen (sp?) at softronic should be able to give a definitive answer.
 
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