I've had the M-Engineering tune on my C2S for over a year now and never an issue, that includes flashing back to stock for a dealer visit. I also have gone back and forth with the E85 tune which is amazing ! I'd run the E85 all the time but do take road trips outside of areas where E85 is available. Their customer service is simply the best ! They are on it and will always respond when you have an issue, even if it's "after hours" . Two thumbs up for M-Engineering!

 

Rudy, is your guest house listed on Expedia, because I’m trying to stay there.

 

Best AirBnB ever. Five stars * * * * *

 

4/5 … loaner C2S had a Stage 0 tune. 🙄

 

2021 C2S, I got the stage 1 91 tune Sepetmber of ‘21 when the car had just shy of 4k miles. Got a CEL about 2 days after the initial install. Reached out to M got a virtually instantaneous response, they had me run data logging, they sent me a new file in about an hour which solved the issue. Subsequently I’ve had them send me a file with the exhaust valves fully open and *** turned off. I’m at 11k miles now and could not be happier with how the car drives. This company’s customer service is so much better than any other company I’ve ever dealt with for any product.
Karl

 

The stutter could be a blow off valve/diverter valve issue. It can happen with a tune because usually tines are more aggressive in getting the turbos to spool up faster. So what happens is that you're at part throttle, so there's not much pressure in the intake manifold. But the turbos are making boost. There's enough pressure difference to overcome the spring force in the bov and push it open. Which releases the pressure in the charge pipe, bov closes, pressure builds back up again until it pushes the bov open. Repeat/stutter.
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To eliminate the stutter with the tune, they can back off the aggressiveness of getting the turbo to spool. Basically make it a bit more laggy.

 

The thing is the stutter is sporadic and throughout several months I've never managed to reproduce it consistently. That's also why I couldn't really find the right chance to take some logs.

 

Sharing my experience here.

I originally got the stage 1 tune installed on my 992S manual in April last year. I noticed a good power increase across the board with stock like drive-ability. I had a few updates sent to me along with 7k RPM rev limiter and PSE on/off and things were great. The car was faster than the 1st stage 1 revision I received, and the PSE option made a huge difference.

Then in July, I installed Kline 200 cell cats along with the Kline exhaust and updated to stage 2. This setup was sublime. Car was a beast and sounded mean. Silly quick I thought to myself. Completely transformed the car, I was happy!

A few weeks later I got a check engine light for catalytic converters. And though I had a stage 2 tune, the map notes still had stage 1 on the label. I asked m-engineering about this and they sent over a update to fix the engine light for the cats along with the tune. Initially this drove fine, but after a few weeks I started to get a stumble/flutter under full throttle at the higher RPMs 5k -6k.

We went back and forth multiple times with datalogs and new revisions, but the car continued to stumble. Sometimes better, sometimes worse. This went on for a few months. Around November I got another update and things got even worse and I got a flashing check engine light and cyl 5 misfire codes. At this point, I was advised to remove the tune because they thought the factory fuel injectors were failing and the cause for the stumbling. The gapping on the OEM spark plugs was also not ruled out, but I only have 3k miles on the car. The reason to go back to stock was to determine if any of the stumbling would happen in stock form and confirm the injectors were the issue. It didn't. Drove fine for the 4 months I kept it stock.

Earlier this month I finally got around to installing new spark plugs gapped down to .022 as recommended. Car continued to drive good, perhaps even better. I figured it was time to re-load the tune. I was advised to run stage 0 map to confirm things looked good in the datalogs, they did and I was sent a new stage 2 tune.
Fingers crossed- went for a drive and sure enough the stumble came back. More datalogs sent and a revision received. Took another drive and it was far better but still had a very slight stumble. I received another revision was told this last revision would fix it and it but it only made things worse.

I was just about ready to give up on this after 9 months, ~18 revisions and countless datalogs, when I suggested we go back and try the original stage 2 tune from last summer to see how that drove. M-engineering agreed and sent me my old file. On Wednesday I loaded the map and voila! car drives great! no stumble, no fluttering, and this thing is powerful!

Mitch, Scott, and Charles have been very helpful along the way, I've been patient also. This a fun weekend car, and when you finally have time to take it out you want to be able to rip on it without having to worry if it will stumble or bog down.

I'm still waiting for M-engineering to analyze what's going on but I'm confident they will come to a conclusion and root cause. I think its safe to say there is nothing wrong with the injectors (at least for now) and the .022 gapped plugs will only help things further.

I do think my experience is an anomaly, I haven't heard about others with similar issues outside of one rennlister whos issues were fixed after changing spark plugs.

 

Thanks for sharing. I have tuned cars much more affordable than my 992 and remember that my ordeal was several years long instead of your 9 months. I was in my 20s then and could spend that kind of time on a tune because I wanted my 3000GT to feel like a 11 second car. Looking back, that experience has kept me from even considering tinkering with the 992, no matter HOW reputable the vendor is. While my 20s car was no Porsche, the 4g63 engine was no slouch either. But that didn’t keep it from producing rod bearing copper flakes in the oil pan.
The day I find the car underpowered, I’ll work to get a torquier car. The three bursts of acceleration per drive is not worth what you just described, let alone the long term unintended consequences of stage 2.

 

I’ve run tunes on most of my previous cars also and my experience has been good so felt comfortable on this car- still do with this latest revelation. my 20s car was a z32 300zx TT with a tune and all the breathers. 420rwhp and being able to keep up with a viper back in ‘02 was too much fun. Before the 911, I tuned my F10 M5 and that was probably as quick as this. Once right they are usually just fine.

 

Nice! I had a 300ZXTT when I was in my 20s as well. LOVED that car! Also tuned w/ JWT turbos, intercoolers, injectors, etc. and pushing about 400 WHP... which felt insanely fast in the mid 90s with no traction control and only 275 width rear tires. Ran neck and neck with 90s Corvette ZR1s and even a 993 turbo on a roll. Good times! And yeah, I love red cars...

 

Are the early 2020 992 models easier to accept tune than newer 2021 and newer ones?

 

Mine is a 2021 so I can't speak for 2020s but I don't think there are any more challenges to tune a 2021 model over a 2020 model. I had no problems at all tuning my 2021 model, but I am on stage 1 so I'm not pushing the envelope. I also have a manual so I don't have to worry about potential DCT issues.

I've installed the tune and reverted to stock and re-installed the tune and installed 3 tune revisions and all went smoothly without any hitches other than having to cleear fault codes when I reinstalled the tune after I got my car serviced. That took a couple of minutes and car has run flawlessly the whole time.

 

So, for those running this tune (stage 1 or certainly stage 2)... The car does ok with putting this power down? I've never had a sports car over 500hp that wasn't AWD so I never worried about traction ... But the stock CS power seems pretty stout. I love revving the engine all the way up ... Just wondering if anyone ever felt the tune was too much power to be frequently usable.

 

The tires need to get up to temp on my GTS, otherwise it’s a skating rink. I have Michelin PS4S at 38psi cold. I remember last year, drove 8 miles to get on highway, 58F outside, punched it while going 40mph and I still spun.