So EFR6758 from Mike arrived today. It's glorious and me a lot happier than I was expecting. I mean, seriously, it's like the 3rd one I get to play with but damn it's like going on a first date with a supermodel.

Overall, I'm most impressed by the original replacement estimate. Borg Warner said "mid-August" and what do you know, it's still August and I have my replacement. I was told that warranty replacements ship first, so other people *cough* Savington *cough* should be getting their turbonators soon (you know, the ones they paid for in 2011).

Definitely glad I stuck with EFR, despite it being expensive in both time, money and stress. I think it was worth it. Mike in particular was very helpful - world would be a better place if all customer service was like that.

Anyways, pictures.
https://www.miataturbo.net/attachmen...ine=1346388917
https://www.miataturbo.net/attachmen...ine=1346388932

More in my build thread - https://www.miataturbo.net/build-thr...12/#post921575

While we would love to take all the credit, solving problems like this can only be done with a combined effort. Once BWTS became aware of this issue, it was they that made sure that we all worked together with the sense of urgency required. As Soviet noted, any outstanding warranty issues are to be resolved before new units for sale will be released, but I can say, we won't be long in having this product back on the shelf for sales.

Thank YOU, Leo, for your patience and understanding during the duration of this issue. It is most appreciated. I look forward to the data we discussed.

Hey, my chinacharger broke, can i has a BW?

you borked your churbo? how?

sledgehammer once he says yes.

Mike, can you speak about what BW might have found as a source of the failures and what was done to remedy the issue from an engineering or manufacturing standpoint?

Should i be able to take off the BW V-band clamp without doing anything special? Tried to take mine off this weekend after ~600 miles and this happened..
I'll be contacting Full Race for a replacement asap.
https://www.miataturbo.net/attachmen...ine=1347766011

Good job i am proud of you.

Use anti-seize the when you put the new one on.

Did you use an impact gun at any point?

Also, get the replacement from Treadstone in Florida. The clamps/flanges that Full Race sells are total garbage.

It's a specific borg-warner clamp though...
I think you over-torqued it. V-bands shouldn't be super-mega tight. Doesn't take much to seal them.

Hell, I had to hit my downpipe with hammer to break the carbon layer. After taking the clamp...

I'm aware. Treadstone makes their own EFR-specific clamps and flanges that are significantly nicer than Borg's own parts.

e: Borg clamp on the left, standard ATP GT 3" clamp on the right.

https://www.miataturbo.net/attachmen...ine=1347932849

Borg clamp on top, standard ATP GT 3" clamp on bottom

https://www.miataturbo.net/attachmen...ine=1347932849

Should you really have a carbon layer at the vband mating surfaces? To me, that sounds like they're not clamped properly or the flares are mismatching.

The only time mine are stuck is when my SS vband female bonds to the iron turbine housing male side. And yes, that is on the turbine outlet. Kroil to the rescue.

Nope. 1/4" drive ratchet to install and remove.

You guys rock. Thanks for the info and suggestions. Ordered from Treadstone.

invest in a can of anti-seize from your local NAPA or autoparts store. best $7 you can spend on a turbo car! i use it for everything from brake caliper bolts to manifold studs and vbands... it seals better, and saves you huge hassles later. it doesnt matter if its the china-made treadstone clamp or the usa-made BW clamp, they will all strip out without antiseize

our clamps are 100% borgwarner OE. If you use anti-seize on the threads (as should be done on all manifold nuts/bolts and all vband surfaces) there is no reason you will have an issue. These are specifically a narrow width to clear the "wastegate tumor", the large diameter traditional vband clamps will hit the housing on the side, so the lower profile fits better and is more compact.

on my personal car ive had the efr downpipe clamp on and off more times than I can count, and havent had to replace it once (i always use anti seize)

Use anti-sieze when taking clamps on and off. You need lubrication for such a long shaft.

Geoff already said that, lol. I'll keep this up so I feel like I still provide value to the forum.

That's what she said. :ky:

It's obvious (to me, at least) that the clamp shown in the initial photo is the O.E. BWTS part.

But, the locking nut is most definitely not, and it's the real root cause here.

To be fair, I work around these parts all day, every day, so goofy details like this are something I'm familiar with.

The 'crimped' all-metal locknut that seems to have caused all of the problem is a design that BWTS doesn't use, period. They use free-running locknuts that use a split design on most U.S.-built product, and, on the EFR Series, they use a free-running 'tall hex' nut that does not have that 'crowned' design. The other obvious giveaway; the "EFR" locknut is a 10mm hex with 1/4"-28 thread, and the one in the photo is a 7/16" hex with a 1/4:-28 thread. Again, I spend far too much time looking at these parts.....

(If anyone needs a side-by-side-by-side comparison photo of these parts, just let me know)

That being said, the photos of the O.E. and aftermarket clamp are correct; the O.E. clamp has a much more narrow 'band' around the clamp, specifically to clear the wastegate port 'lump' on the turbine housing casting. The wider 'band' has a difficult time with this clearance, especially on the B1 housing. This is actually mentioned in the Feature Guide available for free download on the BWTS website.

You can absolutely use the wider 'band' clamps on the non-wastegated housings, with no issue at all, as long as they're designed for the 3.62" o.d. v-flange that BWTS uses, which is fairly standard. But, on the wastegated B1 housings, I suggest sticking with the O.E. clamp.

The O.E. clamp, also, DOES NOT include a locknut when sold as a loose item. It does include a 'tall' free-running locknut when purchased as the hardware kit, part number 179423, but NOBODY buys that kit unless they're installing a Super Core.

The clamp, as a loose part, is part number 59001095225, and we supply the O.E. free-running locknut at no charge when we ship the clamp as a loose part.

I do agree completely with the suggestion of using anti-seize compound on these threads, though. That's wise advice.

I'm sorry that I missed this; yes, in May of 2011, BWTS replaced the original turbine wheel supplier, and all units produced after that date are equipped with these wheels. At this time, we have not been aware of ANY turbine wheel failures with the new turbine wheels, and that includes a complete season of IndyCar, as well as other, less publicized motorsport applications.

Great info thanks.

I'm taking a failure analysis tech elective this semester for my mechanical engineering degree. I chose to do my final report over this issue so your info is helpful. If the report turns out okay ill post it up. Had some fun with the layering light microscope, scanning electron microscope, Energy-dispersive X-ray spectroscopy, and vickers hardness tester on this one.

I have a question regarding the EFR mounting angle, would like to mount mine at 15 degrees or so compressor up to facilitate down pipe packaging, page 78 of the turbo specs state "It is not recommended to install the turbo considerably nose-up or nose-down. It was validation tested to be installed “flat” with respect to the ground"
Wonder if 15 deg would be considerably nose up? And what problems this could be expected form this mounting angle.
Thanks

it is advised to mount the turbo perfectly level - and you can tilt it a little bit, but the closest to level you can get it - the better...

15 degrees is pretty extreme, but it may work, ive got guys who run that angle on drysump motors... I wouldnt personally recommend it, but keep me posted the worst thing that happens is you leak oil into one end and have to take some angle out.

Thanks, I will see how things fit when building the manifold in a couple of months.