A NB8B Turbo progress.

[IanR]

My local tuner was pretty busy, like all of us prior to christmas break so did the best he could to get the car drto pass the gas test for engineering, problems was that the ecu was still running the base tune fro adaptronic and once the tuner started to play with it the drive ability went south, once I has passed the gas test I took it back to get it running better.

After another attempt to make the car smoother of idle and behave itself it was not really much better, just my bank account lighter...time to look for someone who knew what was going on.

I then contacted Anthony at https://www.facebook.com/tunedbyanthony/ as he tuned my old silver NB mx5.

Within 3 minutes hooked to his ecu he was able to tell me that the MAP sensor was out off calibration and needed to be replaced... yep that makes sense for how the car was driving. It was super jerky and hesitant off idle and kicked a bit under load. Back off the dyno and drive home.

Andy at Adaptronic shipped up a new map sensor which is integrated into the ecu main board, at no charge...not even for postage. Talk about looking after his customers and their customers. I have heard nothing but good about Andy and the Adaptronic ecu from those who use them, I have a mate who raced 2 seasons on the base tune out out of the box.

It arrived within the week so booked in with Anthony for the weekend. The new map sensor fixed the drive ability issues immediately as it should and then to tune the VE map for full power and everything in between.

This is where the problems started... this is what it made.



Way under expectation, and no matter what we tried it wouldn't budge...

Back to the garage to look for the source of the lost boost.

[timk]

Even the old TD05 with restrictive SE exhaust housing did way better than that! Hope you get it sorted easily!

[ManiacLachy]

Yeah, something ain't right. I'm starting to see why this car was selling cheap. But I'm sure you'll see it through and on the other side you'll be plenty fast!

Good luck, keep us posted.

[lucass]

Is it running a MAC Valve? Could be incorrectly connected or dead? From what I see the boost is stuck at a set value so wouldn't surprise me if it's just spring pressure and MAC isn't doing it's job.

Can you change the wastegate spring to see if it brings the boost up?

[IanR]

So to find where the missing boost is going, first setup a leak test for the intercooler piping.



And it held to over 30psi no worries...

I found that the cable tie for the pcv valve was leaking at 15psi, so sorted that out.



Next thing was to disconnect the boost line from the solenoid to the actuator to see if the solenoid is faulty.

At this point I will mention that someone had previously run the vacuum lines to between the boost solenoid and the actuator wrong, the result was that the ecu was not controlling boost it was purely only the actuator, it took one look at the efr install diagram to go "wtf" and change it to the correct way.



I then ran the car without the solenoid connected to the actuator It made a slight difference but not enough, the car should make over 20psi in a second or so but its sluggish to 11psi and feels dead...

I then put a bike pump onto the actuator and watch at what pressure it open the wastegate...it was opening at 5psi and fully open at 15psi...hmm might be onto something here I thought.

Next test was to wire the wastegate shut so to see if the spring is failing to keep the wastegate closed...



And BINGO!!! in under a second it makes 15psi and goes absolutely mental! all at less than 1/4 throttle... wicked fun but it hasnt been tuned for over 12 psi so I do it a few more times just letting it build and back off, no where near full throttle nor for more than 1 second... problem solved.

I pulled the actuator can off and the code tells me it is the low boost can, I have now ordered the mid boost can which is pre load adjustable to open at setting between 8 and 16psi, which should be perfect as around 12-15psi I expect it to make 300ftpd, which is the limit of the box and most likely the clutch.

I had not done any of these tests before so it was good learning, reading the borgwarner efr setup info and even Anthony gave me a call and we worked through the tests around the actuator. I really appreciated Anthony's guidance on the phone, even though in hindsight it all makes sense. Now its just wait for the parts to arrive from gcg and head back to the dyno...

Thanks for following!

[IanR]

Is it running a MAC Valve? Could be incorrectly connected or dead? From what I see the boost is stuck at a set value so wouldn't surprise me if it's just spring pressure and MAC isn't doing it's job.

Can you change the wastegate spring to see if it brings the boost up?

Right on track, it is running a boost solenoid integrated to the turbo which talk direct to the ecu, 100% correct the actuator failing to hold the wastegate shut, big lesson here... so much power loss with a faulty part that has been slowly getting worse since I have owned it so can only say its been getting worse for the previous owner as well.

(the sound of everyone with a turbo car running out and testing there actuators...)

[IanR]

Yeah, something ain't right. I'm starting to see why this car was selling cheap.

Every car has its little surprises, it's good to get these biggish surprises out of the way, I am actually glad it was so bad at making power, if it made 250whp and felt half ok then I may have just put up with it for a while, which would have been disappointing. Talking with TimK, is sounded like a little weapon and after the drive with the wastegate wired shut I can feel the potential now.

[speed]

Now I want to check my actuator!
Glad you're getting somewhere

Sent from my SM-A520F using Tapatalk

[IanR]

Now I want to check my actuator!
Glad you're getting somewhere

Sent from my SM-A520F using Tapatalk

This video is cringeworthy but I learnt the basics of testing it...

https://www.youtube.com/watch?v=NN1Hs3L0YYc

Hope you find some lost psi's!

[ManiacLachy]

Nicely done. EFR goodness coming your way! Very jealous.

[Lokiel]

Not surprised you're having issues with the wastegate actuator, there's very little leeway in the alignment of the EFR6258's wastegate shaft before the valve binds, as happens on my custom manifold.

The wastegate shaft MUST move back and forward linearly with NO twist, otherwise the valve will bind (ie. not open or close properly) and you'll get unpredictable behaviour (not enough boost when you expect it because the valve is slightly open, or more boost than you expect because the valve remains closed).

You might need to modify/re-make the bracket holding the actuator to re-align the shaft to move linearly backward and forward; the existing bracket's mount points on the turbo housing are most likely too coarse.

18psi on MT.net has a short video on how the shaft should move (can't find it quickly now so will look for it tonight). The video shows when the shaft's end retaining nut is removed how easily the wastegate valve falls off the shaft and closes when there's no pressure.

ie. Spend your time getting this alignment correct (I think the EFR documentation indicates that there's only a 2 degree margin of error).

On my car they tried modding several of the wastegate actuator shafts but binding was still occurring:


I now have a Ford XR6 wastegate with a modded shaft that binds less than the modified ones above:


I doubt they spent ANY time figuring that modifying/re-making the wastegate actuator mounting bracket was the answer (it's a hefty chunk of stainless steel so maybe that option was too hard?)

[timk]

It's strange though as I wasn't aware of any binding when I had the car. I emphasised to Pete (the manifold builder) that actuator binding was a big problem with these turbos, so the alignment & bracket "should" be okay.

[Lokiel]

I remember discussing this issue with timk when he was building this car so maybe it's not a problem but do PLEASE check that it's NOT the problem now.

ie. It may not have been a problem initially but over time has become an issue (maybe the alignment was on the fringe of being OK but now that the car has been "shaken down" it no longer is?).

Without being bolted to the wastegate valve, does the wastegate shaft start moving BEFORE 5PSI (where you said it was initially opening)?
If so, this indicates that the valve IS binding since the shaft is no longer mechanically restricted at that end.

This is a big problem with the EFR62xx turbos and MT.net has plenty of examples of this - and I'm one of them

I have a new TurboSmart WG actuator with various springs and new Low and Medium BW EFR CANs if you want to do some testing with them - I wont be needing them for several months - PM me if interested.

FYI: Your car has Gina's original MSM front strut brace (catch can plumbing crap deleted) and aftermarket foglight-delete inserts (Gina now uses the foglight mounts for oil cooling and CAI).

I intend to use the TurboSmart on my car eventually when I get around to installing the TSE manifold but the shaft MUST move linearly, otherwise the wastegate's diaphragm will pinch, creating a hole and making it useless:

- diaphragm with pinch hole is sitting on the right of the wastegate actuator)

[Lokiel]

:
18psi on MT.net has a short video on how the shaft should move (can't find it quickly now so will look for it tonight). The video shows when the shaft's end retaining nut is removed how easily the wastegate valve falls off the shaft and closes when there's no pressure.
:

It was actually aidandj's video I was thinking of on MT.net:
... but here's an even better MT.net thread with a video from Savington (Andrew, TrackSpeed Engineering) on how to align the wastegate actuator: https://www.miataturbo.net/prefabbed-turbo-kits-3/efr-actuator-alignment-how-92612/

[IanR]

Thanks Lokiel, the alignment issue definitely makes sense. This unit was very smooth as it opened and closed the wastegate just the actuator is certainly deteriorated as I can open pull the shaft open all the way with my hands, something that John at GCG said should be able to pull only a few mm by hand. Be good if I had weight scales that use the pull movement like hook scales for fish or how we would weigh pushbikes in the bike shop.

Starting to get very excited about this car!