Hi All,
I’ve been a part of the community for a while, but never posted. Please be easy on me! lol

2002 built 1.9L VVT w/ Garrett 2560R running 94octane AKI

I really would love the input of the tuning community on this new tune I received. Here’s the backstory:
Completed a full engine build (if you need build details let me know) with turbo running about 17psi. I had it tuned @ MT Motorsports in Ontario, Canada. The car ran amazing for about a year when I decided to change turbos to a 3071R in summer 2023. I heard that MT had closed, so I went to a local performance shop that I’ve trusted for years with mechanical work. The owner assured me that his tuner is well versed in MS and the miata wouldn’t be an issue. I decided to have it tuned there. $1100 CAD.

I wasn’t @ the shop when the car was on the dyno, but when it was done, I picked up the car. 300whp and 296tq @ 17psi. On the drive home (approximately 10 mins), I pushed it from 2-3rd WOT and coolant shot out of my reservoir. Head gasket had let got on cylinder 4, pressurizing the coolant inlets.

I pulled the head, inspected head and block, valves, lash, etc and put it back together with a fresh head gasket.

I drove the car gingerly for several hundred kilometers, now afraid of WOT. I noticed that the car is now consuming some oil. Finally one day, I thought I would give er the beans, and it happened again; head gasket failure @ cyl 4.

When I pulled the head this time, I noted detonation along the intake side of piston 4 (significant scoring on cyl walls) and the other 3 were quite “dry” looking along the intake edge with very slight scoring on a couple spots.

I have confirmed, tuner did not turn on knock sensor or tune VVT

I’m going through the motions of root cause analysis and would love the community’s input on:
1) root cause
2) tune and tune quality

Thanks a bunch!






Cyl 4

 

I’m not an absolute expert compared to a lot of the other guys on here, but that is a bonkers amount of timing across the board for 94 octane.

VE table looks pretty lazily done in the high load/high rpm zones as well. I can’t imagine your AFRs were consistently hitting their target during high boost pulls.

AFR table is somewhat alarming as well. 11.5 in all the boosted cells is ok (safe), but why is it set to still be hitting 12.5 at 120kpa. Another red flag, there’s no reason you should be running 13.5:1 in the entirety of the low-load area. 14.7:1 in the cruise cells would be considered safe, and most people will lean out all the way to 15:1 or leaner in the cruising areas of the map. 13.5 is just running rich for no reason unless you’re getting up to around 80-90kpa.

Not trying to badmouth anyone but the tune does not look like it was done by someone competent.

 

and fuel is clearly not tuned there. This tune is trouble.

 

Do you still have the original tune file from when you were running the 2560? It probably won't answer any additional questions, I'm just curious as to what it looked like before.

 

Unfortunately I never downloaded it or had a need to look at it. Another newb mistake. I do have a copy of a tune that was two iterations ago. Prior to the built motor, running on different injectors, etc.

 

No sweat, sounds like that was probably pretty long ago.

Well, it's still worth a look if you can post the tune from two iterations ago. Doesn't make too much of a difference but I'm just curious how much of what we're seeing here was on your previous tune and what the tuner messed with.

 

The new tuner initially said he may be able to simply update the 2022 tune, but then said he was going to start from ground zero, and charge the full $1100 for a brand new tune.

 

I would personally be seeking my money back and then some if that's the case. That tune is 100% the cause of your detonation and it doesn't look like the tuner knew what they were doing or attempted to do a thorough job.

 

Can you point me in the right direction to see what a proper turbo tune should look like? I’d love to have something to provide to the tuner as a reference.

 

I don't have my laptop with me but can send you my timing and VE table later tonight when I get home.

Here's a link to my build thread where you can see me get blasted (lightly) after posting about advancing my timing on post #121 (post numbers located on the right side of the page) https://www.miataturbo.net/build-thr...-107372/page7/ and my timing here was still quite a bit less than your tune. I'm currently running this same table minus 5 degrees in the boosted cells.

At any rate, he shouldn't need to be told that it's bonkers to just set large swaths of the boosted cells in the VE table to the same number (all those zones that are just 76, 78, or 80). Again, I don't wanna badmouth anyone because I've got plenty to learn myself but damn that's just ignorant.

There's lots of other ignition maps on 91 on here as well. Most people are in the 10* advance range during peak torque at 17psi. 16-17* is closer to what I run on e85 I think.

 

Jonnie, you mentioned that your engine was built but didn't mention compression ratio that I saw. What did you build it to?

Also, I've never had a dyno tune, but $1100 seems like a lot to me. Again, I have never looked into it, but I'd expect to be closer to $400-600.

 

I'm guessing your tuner didn't properly save the VE Table to the Megasquirt when he was through. There's no way that fuel table would produce 300 hp or even get to 7000 rpm. Think of it this way... let's say your car was starting and idling okay with what you posted. She needs 70 to 80 units of juice in the 900-1400 rpm range. How could it only need 80 units at 17 psi and 7500 rpm?

I'd like to see what your spark plugs looked like.

That's actually a pretty good price. 1100 CAD is roughly 278 USD...

 

Very good, sir.

MX brings up a good point. How was the car driving when this happened and was it making serious power when the HG blew? I'm assuming it wasn't driving incredibly strange since you didn't mention anything like that.

If he's got "Incorporate AFR Target" enabled, that'll flatten out the VE table quite a bit. Fireindc taught me that just recently. My tune has it enabled and my VE table starts at around 70-72 at idle and maxes out at 110 around peak torque at 17psi. That's on a '95 return-style fuel system with a vacuum-referenced FPR, though. Would expect a returnless NB system to have a steeper VE table, not flatter.

Edit: it appears I've just gained senior member status. I dare you all to question anything I say on here ever again. This is my final form. RESPECT ME.

 

Forgot that was Canadian. Not sure how you got 278, but I'm getting ~$820 for the tune (based on $1100 CAD). Still seems a bit high, but not unreasonable.
Granted, if I was paying that much for a tune I'd expect to see an AFR table that varied a bit. Hard to judge everything without seeing the whole tune, but that AFR table seems pretty lazy.

 

I think MX was being facetious lol. Gave me a giggle.

 

I was... and I chose well. I knew no one would believe it was 213 USD.

 

Well shoot, ya got me. I just ordered something from Canada that ended up being around $200 so I was super confused haha.

 

As the closest one to Canada out of the three of us, you should know better, Sim

Back on topic. Jonnie, can you upload a copy of your current tune here?

 

Jonnie, If you have any logs that would be interesting to see as well as the tune. Do you have an AFR gauge in the car? Did it seem like the car was running reasonable AFRs when you were driving it?

 

Here’s the tune. Hopefully this upload works.

I’m running Wiseco 84mm 8.8:1 forged pistons.

The car seemed to be running fine, although hindsight has thinking that I was certainly hearing and feeling knock when I was in heavy boost.