Speaking some more with Sam Stone at EVOMS (kudos to him for answering my questions in detail when I haven't bought anything from them!). He suggested that since the stock master cylinder was retained, maybe some fluid remained trapped there even through a flush. So if indeed mixing the two types of fluid can degrade lines, that could be the issue.

TripleNet, did you replace your master cylinder when you went to the BBI slave, or keep the original?

The GT2 conversion kit uses a different master as well as slave. Also, got clarification that they replace the rubber hydraulic line with a braided steel one, so that might come into play too. (Although they keep the same one from the reservoir, which the mechanic that looked at my car claimed was also compromised.)

I am leaning toward switching to the GT2 kit at this point. Just sucks to have thrown away thousands of dollars on this mod. I'm going to follow up with BBI and see if they'll do anything for me.

 

I didn't replace the master cylinder .... I would say Sam is correct - some incompatible fluid was left in the system and that fried the seals in the BBI..

at least I believe thats what happened to me...

BBI will rebuild the slave for a few $$ (think cost me $300)... flush the system really good and fill with the BBI recommended fluid ..

Thats what I did and the slave has been fine ever since ...

 

Have you tracked it again since then? Also, I'm surprised the seals in the slave would have been damaged without the master's seals and the rubber hoses suffering the same. How long ago was this?

 

2 months ago.... Have not tracked since....

Its the seals "inside" the BBI slave ... the other systems and hoses can handle the various fluids without failure...

 

Unfortunately my experience seems to contradict that. I guess you'll find out next time you track the car. Let us know!

Has anyone else installed the BBI slave, with or without changing the master, and then gone to the track?

 

I tracked the car for a year with the BBI slave and did not replace the master ...

After the slave failed - BBI stated that if there is any fluid in there after the flush it will slowly erode the seals ....

I just haven't tracked the car "since" replacing the slave after the rebuild ...

 

Problem for us 997 guys is you can not drill and tap the 997 turbo gearbox.

 

Yeah. I do like the look of EMOMS' GT2 conversion kit though. Comes with everything, including master, slave, and lines, and is fully reversible. If I had it to do again, would go that route.

Anyway, since you bumped this, I might as well give an update. The original cause of all these issues is still a bit of a mystery, but the hypothesis is that since the master cylinder wasn't changed when the BBI slave was installed, it may have trapped a pocket of Pentosin fluid that reacted with the new DOT4 and caused breakdown of the rubber lines (and possibly the seals in the master and/or slave).

Since I already have the BBI slave, we're going to replace the master cylinder, since it's the only part that hasn't been replaced. While at it, will replace the flexible line to the slave with a braided stainless line from EVOMS. It's actually cheaper than the rubber line from the dealership, so why not, and at least it should last.

Since the slave appears to be operating properly and isn't leaking, going to leave it for now. If I still have pedal problems in the future, I'll assume its seals were degraded as well, and will pull it and send it to BBI to inspect and/or rebuild.

If anyone is looking to do this conversion, I would go with the more time-tested GT2 kit. If you do get the BBI slave though, it's probably a good idea to replace the master and hyraulic line as well. (Master with a new stock part, and line with braided steel.) Also put a new reservoir cap on, calling for DOT4 only, as it appears any accidental Pentosin contamination could basically destroy everything.

 

what a mess!! So sorry to hear about these things....

Few notes:

- OEM clutch line has an updated part number, its a braded line now not rubber.
- both the gt2 and turbo lines are updated, both are the same exact line, the turbo one is longer I've ordered both.

-BBi ships these out without instructions (at least mine did), for something that should be installed in a special manner that is not cool.

That aside, mine has been working fine with some very limited track time, the clutch hose came loose off the fitting and left me stranded once, but the slave itself been a champ so far.

 

So is the GT2 kit doable on the 997 Turbo? Does the transmission need to be drilled and is it possible?

 

Yeah, EVOMS sells this kit: http://www.evoms.com/EVOMS_GT2_Clutc...clugt2slck.htm

It's fully reversible and doesn't require drilling.

 

Sorry about these rookie questions but I thought the GT2 was drilled so how can the EVOMS kit be the actual proven kit/solution without drilling?

 

We designed a bracket that bolts to the stock 996/997TT slave cylinder mounting bosses, and holds a GT2-style slave cylinder in the correct spot to work. We include all the hardware and parts needed to disable the assist, cap the assist lines, and replace the master/assist spring/reservoir cap up front.

 

Why is the GT2 trans drilled? and what do you mean a GT2 "style" slave cylinder? is it an OEM part?

 

The GT2 bellhousing has a mounting pad with drilled and tapped holes on it to allow the slave cylinder to bolt up. It's a simpler way to attach the slave cylinder, but doing that 'right' is only really feasible to do with a giant mill capable of fitting the housing in. Some people will hand drill and tap those holes on a 996/997TT bellhousing. It requires the transmission to be out of the car, and the results can be as-expected for doing a machining operation by hand. Our solution doesn't even require the transmission to be out of the car to be installed.

We take a OE Porsche application slave cylinder and modify it to work with our kit.