FrankenTurbo F21 Longevity update

[Audimilo]

I just ticked over 20,000 miles on my F21's, and as promised here's an update:


First off, let me toss this out there that I have no affiliation with Frankenturbo or Doug, I'm just a customer who went with the turbos I found best suited to my needs at that time. (daily driver car), stock block.


I'm on a 91oct Daz tune, peaking at 25, holding 24 psi on a daily driven Avant, (273,000 miles).

The car is my daily. as suggested, I drive it daily. I commute a lot: about ~ 500 miles a week.

One thing i am religious about is proper warm up. The car never sees over 3k rpm and Zero boost till the Oil temperature comes up. that is CRUCIAL for turbo longevity. even then i ease into the boost for a couple of gears before it sees WOT. with that said, the car sees 24psi every single day.


to date, ive got no issues. I have been hearing a very very lightly increased turbo noise during warm up, but after warmed up, no issues. Could be the winter temps.


Tested my wastegates prior to install, checked all fasteners etc, all checked out good.

broke the turbos in so to speak with very mild driving and minimal to no boost through multiple heat cycles and 1000 miles (new clutch installed at that time too) during that time the coolant banjos weeped slightly, but eventually the G12 did what it does and they sealed up.

oil changed every 3,000 miles.


my k03's were still going at 253,000 miles when i swapped, they were noisy in the morning and leaked a bit, but still hit max boost (MTM stage 2 chip on those)


just fyi, for those who care.


cheers.

[MarlinFoundNemo]

This makes me feel much better about running my stage 2 tune on K03's. I've started getting into the habit of warming the car before boosting but I shall institute your couple other warm up techniques before hitting 20psi :P The turbos had minimal shaft play 10k ago so I want to keep these alive until I can 6mt swap and do bigger turbos. Also, at 253k, how did your turbos look when you swapped to F21's?

[reverse.rake]

good info, thx for sharing. Threads like this will help me make my decision on turbos in the future a bit easier, ive been telling myself to just stick with pj k04 when the time comes but i will gladly go with a set of turbos that cost less if they hold up the same as the borgwarners. it seems the average k03 turbos can last anywhere from 50k - 250k miles, i would hope k04 style can last the same if taken care of as well.

[Audimilo]

This makes me feel much better about running my stage 2 tune on K03's. I've started getting into the habit of warming the car before boosting but I shall institute your couple other warm up techniques before hitting 20psi :P The turbos had minimal shaft play 10k ago so I want to keep these alive until I can 6mt swap and do bigger turbos. Also, at 253k, how did your turbos look when you swapped to F21's?

ehhh they were actually better than i thought. they made a pretty audible "wooooooooooooooooooo" while warming up, but once to temp were fine. they leaked a bit of oil, but again, hit requested boost, and did fine. a bit of shaft play, but less than one would expect. nothing that would be cause for concern.

so, after 253k miles, they were dirty, oily, noisy, but functional, and did the job. i just couldnt leave them alone ...

[Audimilo]

if they hold up the same as the borgwarners. it seems the average k03 turbos can last anywhere from 50k - 250k miles, i would hope k04 style can last the same if taken care of as well.

id strongly remind anyone that nobody's done 250k on a F21 yet. Borgs have done that a few times on other cars. As far as i know im one of the higher mileage F21 sets out there running, would love to hear some more feedback from other users.

[DieselElectric]

I've got a set that were abused for 20k. Been on my car for a little over 7k. 25psi to redline currently.

[Audimilo]

^ nice! thanks for chiming in. thats 2 sets at 20,000 miles +

[slow ride]

Have most of you guys that have f21's also experienced standard k04's and is so do they drive pretty much the same? I'd guess a tiny bit slower spool and better up top? Any more people running the newer mixed flow units?

[Mille Bornes]

I'm at 25k at the moment! 27psi to redline and I usually indulge in at least a quick pull once a day. I'm the same way about the warmup. I drive like a grandma until oil hits temp lol. Mobil 1 0w 40 every 5k

[Audimilo]

I'm the same way about the warmup. I drive like a grandma until oil hits temp lol. Mobil 1 0w 40 every 5k

good call.


slow ride- to answer your question: no i do not have any K04 experience, i went straight to F21's from K03's

[christianb5s4]

ehhh they were actually better than i thought. they made a pretty audible "wooooooooooooooooooo" while warming up, but once to temp were fine. they leaked a bit of oil, but again, hit requested boost, and did fine. a bit of shaft play, but less than one would expect. nothing that would be cause for concern.

so, after 253k miles, they were dirty, oily, noisy, but functional, and did the job. i just couldnt leave them alone ...

That's exactly how mine are, but not super audible. Definitely there though, thanks for the updated. Yikes you commute a lot!

[Peter1.8t]

You guys need to catch up. I'm almost to 80k miles on BW k04's ~26psi.

[DieselElectric]

^ Makes my want to crank my f21's some more....

Maybe by the end of 2016 and I've gotten the wife a new ride/stolen her Saab for DD.

[acoleman]

I'm at 40k still going strong, no noise. Some of the original FTs installed in 2011. Like the OP, proper warm up and cool downs. 25 psi EPL tune.

[Audimilo]

You guys need to catch up. I'm almost to 80k miles on BW k04's ~26psi.

Properly cared for Borgs should last a long, long time. I had 250,000 on my borgs... maybe YOU need to catch up ;)

I'm at 40k still going strong, no noise. Some of the original FTs installed in 2011. Like the OP, proper warm up and cool downs. 25 psi EPL tune.

Excellent to hear.

[Audi9]

Cool to see a long term update

[Peter1.8t]

Properly cared for Borgs should last a long, long time. I had 250,000 on my borgs... maybe YOU need to catch up ;)

Lol I couldn't wait that long for them to die, so I opted to upgrade early. Still have my k03's sitting in a box in the garage, great condition.

[jpurre]

15k+ miles here, no turbo issues at all, running 3F tune 21psi.

[Audimilo]

Awesome. thanks for chiming in fellas.

looks to be like most folks are having good longevity with the F21's thus far. I gotta be honest.. what a FUN daily driver the F21 setup is!!

[jturnbull]

Close to 35k on mine no noise that I'm aware of. 25psi everytime I drive it. Just wish they spooled a bit quicker.

[DieselElectric]

Close to 35k on mine no noise that I'm aware of. 25psi everytime I drive it. Just wish they spooled a bit quicker.

How late do yours spool? I just pulled up a 3rd gear log, starting at 2k, and hit 20psi at 3100rpm. Granted, I don't reach full boost until 3rd gear, but that's because the car is just stupid quick through 1st and 2nd. 1st and 2nd are both right around 22psi, and 3rd on up peaks 25.

[slow ride]

That's not bad for spool, what do you think a k04 would be 300rpm sooner?

[01audia4]

Around 25K on mine, and I always boost around town / on the highway. No issues here, only at 22PSI though. 24 on E85

[AudiSportB5S4]

I have been hearing a very very lightly increased turbo noise during warm up, but after warmed up, no issues.

FYI - you can chalk that up to DVs in the cold temps/winter. What type of DVs are you running?

Have most of you guys that have f21's also experienced standard k04's and is so do they drive pretty much the same? I'd guess a tiny bit slower spool and better up top? Any more people running the newer mixed flow units?

You have it right.. I have K04s, and have been in/logged over a dozen S4s running FrankenTurbos and I would say yes to slightly slower spool (could even be due to hardware diffs.. it was maybe 100rpm) and then up top they are slightly better at holding boost and continuing to make power.

[01audia4]

Have most of you guys that have f21's also experienced standard k04's and is so do they drive pretty much the same? I'd guess a tiny bit slower spool and better up top? Any more people running the newer mixed flow units?

I had K04's in my old S4 with just about the same setup as my F21 car now, not much of a difference, maybe a tiny slower spool but I wouldn't say that is very noticeable. Still perky around town.

My Meth K04 car and Non-Meth F21 car run the same FATS. (different tunes, EPL Meth vs Daz F21) - I also had a Lee tune on the K04 car, ran the same as EPL.

[slow ride]

Thanks guys, good info, sorry to bore the rest of you haha. I just want my S4 setup to spool slightly better than the twin 6265's on the vette, but that car is almost worthless under 100.

[01audia4]

Thanks guys, good info, sorry to bore the rest of you haha. I just want my S4 setup to spool slightly better than the twin 6265's on the vette, but that car is almost worthless under 100.

I saw logs of the SRM K04's and was pretty impressed, I wouldn't rule those out - I would love to see them VS the F21 mixed flow..