Should I replace or rebuild my turbo?

rang-a-stang

rang-a-stang

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My troubleshooting is leading me to a failed oil seal on my exhaust side. Car has 135K miles, original turbo, and only a few bolt ons (stock TMIC for instance, HPFP internals). I want this car to last almost forever and am willing to sacrifice some power/potential power for reliability/longevity. On the same note, I am willing to pay to "do it right" and if that results in more power, awesome but not at the cost of reliability or longevity of the turbo, motor, or trans.

I see I have a few options
1) Pull the turbo, replace the oil seal or cartridge, clean the whole housing, and re-install.
Pros: Cheapest, probably the easiest, probably the most reliable
Cons: no power added, could fail in the same way again soon, no warranty

2) Replace the factory turbo with a drop-in like CST4
Pros: tons more power than stock, brand new turbo so it should last, 1 year warranty on CST4
Cons: Most expensive option, would need a tune (I have an Accessport running an OTS tune, and have tuned using TunerProRT on my jeep but not sure I could do this car), might shorten the life of my longblock, might shorten the life of my clutch, my wife would divorce me over the $$$$ spent.

3) Pull the turbo, send out for rebuild
Pros: A professional turbo rebuilder probably offers a warranty, low'ish cost, better reliability than if I did it myself but not necessarily
Cons: Have to ship my turbo out, no power added, wait time while they rebuild it and send it back

4) Buy a new factory replacement turbo, R&R the stocker with a stocker
Pros: first turbo lasted 135k miles, so another one should too, 3 year warranty, medium cost, no tune work needed, super easy to do.
Cons: no power added, a factory turbo is not that much cheaper than a CST4 from what I am seeing. I don't like the idea of replacing an entire turbo when only a seal failed.

What am I missing? I am more of a Jeep guy and this turbo/DIZI/Mazdaspeed stuff is new to me. Are the CST4's lasting as long as stockers? Other than the tune and turbo, are there other costs I should be aware of if I go route 2? Who has rebuilt their own turbo? is it as easy to rebuild as other turbos? Are there good mods I could do if I do option 1?
 
Drop in a BNR S2 or S3 and call it a day. Get rid of that hair dryer K04. You'll be happier.
 
I have no idea of the quality, but I bought this to replace my OEM turbo which is spewing oil. I haven’t installed it yet and so I can’t even say my own experience, but it caught my attention because wasn’t expensive :) After receiving it I can say that it seems decent enough as far as I can tell.

https://www.ebay.com/itm/252652480531

Once I install it I can rebuild the OEM turbo and have it ready if this one fails.
 
I'd look for a low mile used k04 on the facebook groups, or get an S3.

My gen 1 cst4 started blowing some oil out the compressor at like 30k miles so that was cool.......

The BNRS2 uses a GT28 wheel afaik. So you lose spool and gain little power over the k04. I think the S3 is the perfect turbo if you want to go bigger.
 
I happen to have a k04 in my garage if you're interested in going that route. Only 10k-ish miles on it. Never smoked and in good shape. Not sure about shipping cost across the country...
 
Cst4 is bigger than you want in my opinion.
 
Copy that, Mazdarati.

jsilva, that makes sense. I hate storing parts and will be moving out of state soon and don't want to bring parts with me, otherwise, I would spend more time researching that option.

Good info mangosmoothie. I'm not on FB, insta, or other. I have been watching Craigslist and ebay but just don't trust them enough to spend the $ and time to swap. I am researching S3 based on your and Mazdarati's inputs.

Flyhigh, Not sure how to contact you, but I am interested! (I just signed up on this forum this week and am still learning it).

Ok, roger that, Easter Bunny. Thanks.

Are parts for S3 easy to come by (if I have problems in the future)? S2 looks only to be about $100 less than S3 so S3 seems to make more sense. Is it reasonable to think I can do my own tune with my Accessport V3 after an S3 install? I think if the S3 is about $1200 I might be able to swing that. But if I have to add another $500 to have a tune done, I may have to sell one of my kids.
 
Can the BNR S3 be detuned to similar stock power to avoid some of the other supporting mods? I.e. 3-port EBCS, 3 bar MAP sensor, etc.?

Just curious because there could be costs for other supporting mods if the S3 can't run on the stock EBCS. The costs can definitely add up.

I haven't researched it for some time, but I thought BNR also sold an S1, which is essentially the K04, but improved mechanically. However, if the S3 can be installed without the other supporting mods, then this would be the way to go...OP may change his mind very quickly about keeping things stock or fairly close to, haha.

For the record, if my K04 blows (no pun intended), I'll be going the BNR S3 route with these supporting mods (high flow catted downpipe, 3-port EBCS, 3 bar MAP sensor, and BPV in addition to my intake and TMIC).

I think a custom e-tune is in the range of $150-$200 USD. I'd get it professionally tuned by one of the big names (Freektune, Purple Drank, Hypnotic, or Stratified). You can have the car tuned conservatively...also, if you don't drive it in boost constantly, I doubt it would change much in terms of reliability.

Apologies if I am misinformed on this topic.
 
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You can get away with the stock map sensor and a cobb intake or similar if you don't go past ~20 psi. I bought my cst4 used with like 20k miles on it or so. The car it came off of had the stock map sensor, stock intercooler, and a cobb intake. so all was fine there. I think it was just tuned to like 18 psi across the board. Made like 290 whp on 93, plenty of room for more if you want to upgrade other parts. With the cst4 you can use the stock ebcs because it has 2 ports on the wg actuator, just like stock. The S3 does not, and you'll probably need a 3 port.

But yes, you can definitely get away with not throwing the sink at it. EBCS is just a mac valve, they can be made for like $50.

And the S1 also uses a GT28 wheel according to BNR site. So the S1 and S2 likely lose some spool over stock and gain almost no power. It probably isn't noticeable on a stock motor car. They're probably more durable than a stock K04. But if I were paying that kind of money I'd rather get an S3 and gain some power.
 
_Mazdarati said:
Drop in a BNR S2 or S3 and call it a day. Get rid of that hair dryer K04. You'll be happier.
Click to expand...
/ Thread.
But seriously this is a fantastic option. If you just want a stock ish replacement with some power improvement S2, if you want more power and a turbo that won't goes wonderfully on a stock block then an S3. They'll outlast a new k04 without question
 
OP I would not assume that your OTS tune is "safer" than a higher hp tune and a larger turbo. These OTS tunes make you feel fast by rolling on a ton of torque low in the rpm range, which is what really puts stress on the bottom end. I would be more nervous running a K04 with an OTS tune than a S3 with a proper tune that adds power as you add rpm. Food for thought.
 
Today I am going to start cleaning my valves and get the new PCV installed.

In the meantime:
Looking around on this forum and doing some reading, this is how I understand a minimum S3 Install would cost:
S3= $1150
3 BAR MAP= $40
Pigtail for MAP= $30
3 Port EBCS= $80-$120
Turbo inlet coupler= $20
Tune= $200-250
Shipping, unexpected costs, and taxes=$100
So cost would be $1600-1750 depending on which EBCS, which tuner, etc. I don't see any special fluids, adhesives, or tools I would need that I do not already have.
My choke points would be the stock down pipe and TMIC but I am ok leaving those for now. I would assume this would net me a combo that is reliable, some (not tons) more power, and is only limited by the DP and TMIC.

It's tough because that's a huge number in our budget right now but it seems like the right way to go. Or I buy a used K04/cartridge now, and start prepping for an S3 in the near future. I may do another K04 now, then start buying the other stuff (MAP, EBCS, TMIC and DP) over time so when the second K04 pukes, I am spending $1150 instead of $1700. hmmm... I sense a tense conversation with the wife tonight.

BTW, I super appreciate everything you guys are posting! I know I am a newb and appreciate the time you guys are taking!
 
The Facebook ko4 guy with the upgraded chra, sells his for 400-450. On a budget, this is the way to go imo. He has some pretty good feedback on the group and he offers a 1 year warranty, same as BNR.
 
"the Facebook guy" sounds super sketch. how new is he? For similar price BNR is proven to be very reliable
 
I assumed OP knew who I was talking about, as he was referenced earlier. He's being doing it for over a year and has sold over 60, with zero issues
 
One thing to strongly consider is that the $200 - $250 you'll be spending on custom tuning for the S3 will be a sunk cost, because if you decide you want to start modding for more power with the S3, I think it would be a second custom tune for your additional mods. This may be incorrect, but a lot of the tuners I mentioned had project cars for which their OTS maps were based on, which was with a K04. So even though these are OTS maps, they're based on their own modified cars and by this time are very dialed in for our platform. For the record, a flash tune costs about $50 and is often included in the price of a new part you're adding to your K04 setup.

I think if BNR or the Facebook guy can rebuild a K04 for $400-$500, this would definitely be your best bet IF you dont plan on modding further and keeping close to stock power. That or trying to find a low mile used K04.
 
Probably around $300 for a full tune... revisions later for adding things like a new intercooler are usually around $50 per revision not mod (ie add IC and DP as one cost) Swapping the turbo or additional aux fuel usually requires a full re tune as far as prices go but that's a per tuner thing I'm basing this off of freektunes website as he's who I've dealt with over the years

Also who's this Facebook guy? OP has stated he doesn't have Facebook.
OP @Flyhigh also offered up a k04 no smoke with 10k miles on it... that could be a very cheap solution and drop in. Reminder if you go that route both of you need to donate and create a For sale thread in that section even if it's "making FS thread for @name here's the pic"
 
@Awafrican, thank you for the correction. That makes a lot more sense than what I was saying with regards to the cost of revisions.

I guess my point is that there's not a lot to gain by spending the $200 or $300 on a custom tune for near stock performance if theres no plans to modify for more power.

If you're considering putting in a BNR S3 because of reliability concerns, 135,000 miles on the original stock K04 is pretty good. That's not unreliable in my books. I have 122,000 miles on my K04 currently.

For the record, I'm not crapping on the BNR S3...that's the one I want when my K04 dies. But I wont be making the decision to switch to that turbo based on reliability, it will be to make more power.
 
I'm tracking everyone here.
1) I do have Autotech HPFP internals installed.
2) I am not sure who the facebook guy is. I am not against doing business with him (I could use my wife's facebook to get to him).
3) I am OK paying for a tune now, and an update later. Honestly, it will be at least two years before I could get a DP and TMIC anyway so that cost will be absorbed over time anyay. I know running an OTS tune is not ideal for my current K04 setup and I have been wanting a good tune for a while; it has just been so low on the priority list. I also know running an OTS tune is not an option for an S3 so really that cost that needs to happen either way.
4) I had a conversation with Flyhigh and his turbo is a strong option and is on the table. When the wife and I talk tonight, I will either send him money for his turbo or drain my emergency fund and order an S3, MAP, EBCS, Boost tubes, and start figuring out who I am going to tune with. Really, I WANT to go S3 because I think in the long run it will be amazing and cost wise, it's really cheaper (since I will buy going that way eventually and anything done now is just delaying the cost). The decision will come down to whether or not the boss and I can agree. I got a 50/50 chance of that happening.

If I do S3 I will start a couple new threads for advice on selection the best EBCS, MAPs, and tuner.
 
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