Super-Cheater K04

[zenit]

Ported K04-882 (Mazdaspeed) Turbine Housing
-Heavily ported turbine entry housing & wastegate. No porting past the first bend of the housing.
-Bored and radius'ed for larger turbine wheel
-Wastegaste bored 2mm over.







Ported K04-582 (CX7) Compressor Housing
-Light porting of whole A/R.
-Bored and radius'ed by Turbolab for larger billet compressor wheel







Turbine Wheel
-Mamba "Extreme" K04 Turbine
-Clipped 10 degrees and balanced with comp wheel by Bullseye Power
K04 Extreme Turbo Turbine Wheel Borg Warner K03 K04 AUDI VW






Compressor Wheel
-Turbolab billet wheel





Bottom line:

Why are you doing this, when you could buy an atp or S3?
I wanted to have fun with non-stock turbos, but be obviously breaking stock/prepared class rules of AX/rallycross based on visual inspection.

Will it work?
I don't know, let's find out.

Well, if it works, how much power will it make?
I guess- IF it works, it might make somewhere between an S2 and a S3, just based on the size of the turbine wheel and compressor wheel.

Why did you use a CX7 Compressor housing- isn't a Mazdaspeed housing better?
I bought a used turbolab modified turbo to start this project that came with that housing, but as far as I can tell, the only major difference between the CX7/MS compressor housing is the inlet diameter (which was bored out for the larger compressor wheel anyways).


Reference:
K04 Differences: K0422-582 vs. K0422-881 / K0422-882

k04 CHRA pictoral disassembly

[Djohns]

Looking forward to your results!

[KiwiFlavor]

Originally Posted by Djohns Looking forward to your results!

I second this!

[WetzMS3]

@zenit; projects are the best projects.

[WAMBUSHHHH!]

interesting. Subbed.

[kpeezy188]

I'm curious to see your results.

[LowFlyin]

In

Sent from my LG-H820 using Tapatalk

[sheston]

This looks very interesting. I've tried to do just about everything on a budget and this fits right in.

Hope you got some good logs before to compare with after,

Thanks

[zenit]

Turbo makes boost. Stock tune is stock tune though, and BCS systems are doing their job. ~14psi on 30-50% relative throttle and 30% wgdc. Plenty of room to grow.

[MSMS3]

So you have to run stock tune? I'd want to carefully datalog to make sure stock tune does not produce undesirable or unsafe conditions. I would think any real gains would not show up without a tune, and that there might be some flow related side effects that might not be good.

Please post some datalogs.

[zenit]

Originally Posted by MSMS3 So you have to run stock tune? I'd want to carefully datalog to make sure stock tune does not produce undesirable or unsafe conditions. I would think any real gains would not show up without a tune, and that there might be some flow related side effects that might not be good. Please post some datalogs.

There will be tuning, that was always the intention.

Not posting these preliminary logs just yet, as all the data shows is that a tune needs to be developed for the car/turbo.

But I will, once I have a tune and more meaningful data to post.

[BAT-man]

Quick update on some issues with the hybrid turbo I got from Turbolabs, I advise the OP inspect your turbos' specs, just to make sure you got what you think you got, since I really cannot trust what they say after my experience: K04 Differences: K0422-582 vs. K0422-881 / K0422-882

TLDR: Sent 582 ex. housing claiming it was negligibly smaller than 882, and that they ported the difference out. Lied. Had to reuse old 882 ex. housing.

Having said that, we now have turbos which have very similar intake specs and 12 clipped and unported exhaust side (mine) vs. 9 clipped and even more ported exhaust side (yours). Can't wait to see how much of an impact this has, the 9 blade wheel is such a cool idea, I'm sad it wasn't available a few years back when I ordered my hybrid.

My initial results on v-dyno are a much improved and flatter top end. The car felt like it struggled less after 4k rpm. I cap the boost to 17psi after 5k, running 18ish 3.5K-5K.

[zenit]

periodic update:

Tuning adventure with the super-cheater k04 hit a temporary wall when I maxed out the stock airbox maf voltage (>4.9v) at ~2.3 load.

So I relocated the battery to the trunk and installed a 4" HTP intake.


In the process of which, I found this:



Caused by this:
(A lock washer that somehow made it into the airbox)


In the spirit of using a broken part justifying the expense of a new, more ridiculous car part, I bought this to replace the broken turbo labs wheel:



With these specs:

Inducer Dia.: 51.03 mm (vs 50mm Turbo Labs)
Extend Tapered Tip Exducer Dia : 66.13 mm vs (65mm Turbo Labs)
Exducer Dia. : 61.98 mm vs (60mm Turbo Labs)
Wheel: 7+7 (vs 6+6 Turbo Labs)

I bored out and polished the housing for the new wheel:


The turbine and compressor wheel are currently being balanced at R&S Distributing in minooka, il: hopefully it will be ready for pick up and install tomorrow.

In the meantime, I've played around with squeezing what I can from the stock mazdaspeed k04 as a baseline. Note that the AFR is actually Lb/min numbers. Only mods are: Autotech internals running E25-E30, and 4" intake (both OEM cats still there). 2.2 max load, tapering to 1.5 in the dyno below:

[sheston]

How does the lock washer damage the turbo and then end up back in the filter?

You should like the HTP 4 in. I've got one on my K04 as well. I went with a 9 lb braille battery to make it fit :-)

Can't wait for the compare

[zenit]

Originally Posted by sheston How does the lock washer damage the turbo and then end up back in the filter?

No idea. I'm fairly sure it wasn't from the engine bay.
It was clearly bouncing off the compressor wheel.

Originally Posted by sheston You should like the HTP 4 in. I've got one on my K04 as well. I went with a 9 lb braille battery to make it fit :-) Can't wait for the compare

I do like the 4"er. Spool time is silly, even with both cats.

[zenit]

Well, initial vdyno results are in.



The above vdynos were done with nearly the same tune, except that the boost/load targets and limits were raised for the super-cheater.

I think the next step with this project is unrestricting the exhaust. I think that maybe the turbo is not at it's max speed, due to the less restrictive hotside and larger turbine wheel- although that doesn't explain the loss of power in the higher rev range (5K+), since I gained airflow in this area. Hopefully my tune's unaltered ignition timing curve isn't past MBT in this area, with this minor gain in airflow(right?)

[Mazdazilla6]

Is everything okay in the log? Throttle opening completely? Are timing curves similar? That vdyno doesn't make sense lol

[zenit]

Originally Posted by Mazdazilla6 Is everything okay in the log? Throttle opening completely? Are timing curves similar? That vdyno doesn't make sense lol

Everything looks okay in the logs, nothing crazy or unexpected happening.

timing curves are identical- I didn't adjust that at all.

[Mazdazilla6]

I'm hard pressed to believe the turbo isn't spinning fast enough. If you're flowing more air, then you should be making more power, yet you have the complete opposite. There has to be something that's being overlooked.

[zenit]

Originally Posted by Mazdazilla6 I'm hard pressed to believe the turbo isn't spinning fast enough. If you're flowing more air, then you should be making more power, yet you have the complete opposite. There has to be something that's being overlooked.

The turbo not spinning fast enough, is a separate issue from the power drop in the upper rev range issue, I think.

I wonder if it's the BPV. Currently there's a stocker bolted on right now that previously had leaking problems on racecar (a 6). I put it on, because in the first instantiation of the super-cheater, OEM was the only BPV I had that wouldn't make the Super-Cheater surge on throttle lift. I kept it on with the K04 and it made good power and didn't leak (as far as I could tell in comparison to when it was leaking on the 6).

It's possible that with that something is different enough between the K04 & Super-Cheater that the valve is leaking/recirculating air under boost.

[Mazdazilla6]

Originally Posted by zenit The turbo not spinning fast enough, is a separate issue from the power drop in the upper rev range issue, I think. I wonder if it's the BPV. Currently there's a stocker bolted on right now that previously had leaking problems on racecar (a 6). I put it on, because in the first instantiation of the super-cheater, OEM was the only BPV I had that wouldn't make the Super-Cheater surge on throttle lift. I kept it on with the K04 and it made good power and didn't leak (as far as I could tell in comparison to when it was leaking on the 6). It's possible that with that something is different enough between the K04 & Super-Cheater that the valve is leaking/recirculating air under boost.

Lol the same valve Farhan was having issues with? Stockers are cheap, would definitely be a good place to start.

[zenit]

Originally Posted by Mazdazilla6 Lol the same valve Farhan was having issues with? Stockers are cheap, would definitely be a good place to start.

valve tested bad. I swapped a turbosmart one after some reworking/finagling/oiling/spring swapping to keep it from surging the compressor and trims jumped 15% and spool and sustained load improved. I forgot the tuning laptop, but things noticeably improved.

I honestly don't know why this wasn't an issue with the k04 on my car.

anyone have turbosmart blue spring they want to trade for?

[Djohns]

Originally Posted by zenit valve tested bad. I swapped a turbosmart one after some reworking/finagling/oiling/spring swapping to keep it from surging the compressor and trims jumped 15% and spool and sustained load improved. I forgot the tuning laptop, but things noticeable improved. I honestly don't know why this wasn't an issue with the k04 on my car. anyone have turbosmart blue spring they want to trade for?

You can have my stock valve if you want it.

[Jeff23spl]

you talk about surge on throtle lift off, i'm curious to read more about it because i never tried the oem one but i have the same issue with a stock RX7 BPV or any spring or shim combo with a Forge BPV. It started righ after switching from bushing k04 to ball bearing gt2871. Lub or a brand new Forge rebuild kit doesn't help much...
I finaly get use to drive it around the problem....but i would like to solve it too

I'm waiting for an oem to be shipped and will try it. I don't see how it can leak under boost as you should have same pressure on top than below...Maybe at spool or with a too restrictive intercooler....? Will try and see...

[speed23]

As I believe Jeff was pointing out, it cant be a leaking BPV as the dyno is showing that you are getting more boost with the new turbo. And boost is measured after the bpv, so what your measuring is what your getting into the engine. You sure timing is the same? Logs would be interesting to see!

[sheston]

Just a note: I'm back to using my stock BPV after breaking 2 Synapes, holding 30+ psi with the simple mod on here somewhere. You block off the extra port that I believe is there to help it switch faster.

[zenit]

Originally Posted by Jeff23spl you talk about surge on throtle lift off, i'm curious to read more about it...

Simple. The throttle body closes (you lift your foot) the air from the still spooling turbo gets further compressed in the intake pipes pre-throttle to the point that it flows backwards through the turbo.

This is a good video

Originally Posted by speed23 As I believe Jeff was pointing out, it cant be a leaking BPV as the dyno is showing that you are getting more boost with the new turbo.

Sure it can. The BPV can also crack open partially, bleeding off some of the building pressure (but not all).

Originally Posted by speed23 And boost is measured after the bpv, so what your measuring is what your getting into the engine.

Unless the boost leak is largely being recirculated, and/or leaking from the housing of the BPV.

Originally Posted by speed23 You sure timing is the same? Logs would be interesting to see!

Absolutely sure that the timing is the same.

Regarding the leaking BPV- I'm fairly sure this is what happened:



Pressure differential due to leak at the top caused the BPV to crack open.

Regarding the reduction in spool time from swapping out the leaking BPV, I'm beginning to think that swapping to a larger compressor wheel dropped the vacuum that intercooler cold pipe saw, pre-spool. Racecar (k04 with CS TMIC intercooler) had the similar issues with spool, but not with sustained boost- and it likely saw a reduced vacuum due to the less restrictive intercooler. But my 3, which uses a stock intercooler and k04, produced enough vaccum to keep the BPV sealed until the K04 insta-spooled.

Originally Posted by sheston Just a note: I'm back to using my stock BPV after breaking 2 Synapes, holding 30+ psi with the simple mod on here somewhere. You block off the extra port that I believe is there to help it switch faster.

How did you break the synapse valves?

[Jeff23spl]

i know what it is but i'm curious to hear about your work around it if you find something. For myself it is when i go full boost but release the pedal too slow. Not sure if it do it because of the valve is too weak and fluctuate open-close or if it is too hard to initially open for the small pressure difference i apply in that case(Stuck in the o-ring a bit)...I was looking for spring rate below and above the 3 one i got with the valve to test but i'm a bit lazy

where you point for the leak, is it around the factory crack or yours was broken ?

[GroceryGtr]

subbing to see where this goes. Cant justify the EFR pricetag for my summer fun car, and would like to find a way to get more efficiency/power out of the k04 and keep the silly fast spool times it offers over the s3/cs options.

[Jeff23spl]

Originally Posted by GroceryGtr subbing to see where this goes. Cant justify the EFR pricetag for my summer fun car, and would like to find a way to get more efficiency/power out of the k04 and keep the silly fast spool times it offers over the s3/cs options.

Lag goes with turbine size, a k04 machined for a larger comp wheel = CS...

But have you tried a speed with a small bt upgrade ? Lag isn't really bad if you got with a small upgrade. I personnaly have an old gt2871 + fmic piping and i need to drive a stock speed to see that mine is lagging a little bit more but it is not bad on dayly driving.

[GroceryGtr]

I thought the CS was using an 18g housing if I'm not mistaken and I didn't think the OP was going that crazy with machining. problem is my DD is a stop and go traffic sub 45mph drive 95% of the way so a few hundred rpm increase is a very noticeable difference. I'd love to have the extra top end for when I goto the airport or run errands, but I'm not willing to sacrifice my DD route to do it currently. My build specifically goes after generating the most tq/whp from say 1500 to 3500 rpms. Its one of the main reasons I went forged build, bc I knew my goals were to generate a ton of low end power, not so much to support the top end power of a BT build. I love the k04 characteristics, so I'm just curious to see if there is a little more power to be squeezed out of it. Only way I'd upgrade is if the CS was able to get within 200rpms of the spool time(currently everyone seems to be reporting 300-600rpm slower) or if I got a silly sick deal on an EFR.

[zenit]

Originally Posted by Jeff23spl i know what it is but i'm curious to hear about your work around it if you find something.

Sorry, I misunderstood.
In short- I had two Turbosmart BPV's:
-I paired the BPV housing and piston that were the least scuffed up with the screw-on-top with the best sealing port.
-I cleaned, polished and oiled the housing & piston with a lightweight hydraulic oil (shock oil).
-I assembled with the lightest spring I had (green versus pink).

Even with the lighter spring, there is still a little some hesitation/surge behavior on/off partial throttle, but it's not audible and obvious like it was before. The lightest weight BPV/BOV spring from TurboSmart might do the trick, but instead I bought a used GFB respons valve. Should be here this week.

Originally Posted by Jeff23spl where you point for the leak, is it around the factory crack or yours was broken ?

It was leaking at the seam where the factory valve is assembled.

Originally Posted by Jeff23spl Lag goes with turbine size,

I think it's more valid to say that lag is related to the energy required to spin the turbine wheel- and there are exceptions and qualifiers to this big wheel = lag relationship. I.E. EFR's lightweight(low inertia) turbine wheels, flow efficient twin-scroll housings or small A/R housings which pump up the numerator of the pressure ratio across the turbine, etc.

Originally Posted by GroceryGtr I thought the CS was using an 18g housing if I'm not mistaken

I thought it was 18g CHRA in K04 housings.

Honestly, I wouldn't mind trying this out as a drop in K04 upgrade.

[Mazdazilla6]

Lag is just foreplay.

[zenit]

Originally Posted by Mazdazilla6 Lag is just foreplay.

You better get that twin scroll bolted back on. Lag is closer to ED than it is to foreplay

[Mazdazilla6]

Originally Posted by zenit You better get that twin scroll bolted back on. Lag is closer to ED than it is to foreplay

It won't be for a while. In the mean time I'll just have to feed the turbo fuel.

[Jeff23spl]

Originally Posted by GroceryGtr problem is my DD is a stop and go traffic sub 45mph drive 95% of the way so a few hundred rpm increase is a very noticeable difference. I'd love to have the extra top end for when I goto the airport or run errands, but I'm not willing to sacrifice my DD route to do it currently. My build specifically goes after generating the most tq/whp from say 1500 to 3500 rpms. Its one of the main reasons I went forged build, bc I knew my goals were to generate a ton of low end power, not so much to support the top end power of a BT build. I love the k04 characteristics, so I'm just curious to see if there is a little more power to be squeezed out of it. Only way I'd upgrade is if the CS was able to get within 200rpms of the spool time(currently everyone seems to be reporting 300-600rpm slower) or if I got a silly sick deal on an EFR.

ok i got it, you like low end torque. but is it on a 3 or 6 ?

[Dommo14]

subbed

[GroceryGtr]

I have a 6. On a side note nice to see a probe guy still around... I had a fsze swapped 95 mx6 and then a turbo fsde mx6.

[sheston]

If your lag lasts for more than 4 hrs, see a doctor for a smaller turbine

[impossible]

GroceryGtr is your bottom end built? If not then stop bothering with chasing 'instant spool' turbos.