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      03-02-2013, 11:05 PM   #1
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650i GranCoupe TMC tune

Just received my TMC tune from the mail. I also ordered JB but I made a mistake of ordering the wrong harness, so I had to sent the harness back and wait for the right one......



And here it is installed in the engine compartment.



Installation was fairly strait forward according to the included guide. This unit was for the F12 650i which had the N63 engine. I inquired about the unit for N63Tu in the gran coupe and was told to use the same unit.

Just installed yesterday afternoon and didn't have time to really test it yet. But no engine light or any fault lights so maybe I will try the car today......
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      03-03-2013, 01:18 AM   #2
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Nice find! On the site, tmcmotorsport.com, it says from 408 hp to 489 hp with this tune. 2013 N63 already has 445 hp. What is the gain on 2013 N63 engine?
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      03-03-2013, 02:43 AM   #3
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Originally Posted by neversummer78 View Post
Nice find! On the site, tmcmotorsport.com, it says from 408 hp to 489 hp with this tune. 2013 N63 already has 445 hp. What is the gain on 2013 N63 engine?
When, they only said similar gains as the N63. I am happy if it hits 500hp
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      03-03-2013, 02:55 AM   #4
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Just went thru a test drive with the TMC tune on my 650i GC with a friend. Some quick 2cents comments:

1) Below 2000rpm, the gains are there but not very noticeable. Possible due to the fact that the 650iGC has more than enough low-end torque. My feeling is that if the low-end torque goes any higher than now with boost, the rear axle may have problem putting those torque down to the road......

2) Above 2000rpm, the gains are VERY noticeable. In comfort mode, there is a much firmer push from the back feeling when accelerating and response is fabulous as well. In sport mode, I can only describe it as a major kick in my butt! I did a pull all the way to 5500rpm and is nothing short of amazing!

3) Gas consumption? Well, I only had it since last night so a bit premature to draw conclusion yet. Let me revisit this after a few weeks.......

4) My feeling is that adding the TMC (or other tunes) to the 650i GC is great if one wanted more power to the car off the straight line but I don't think the 650i GC is lacking in the power department to begin with. I am now more concerned about the 650i GC control of such power. When stepping on throttle even at 75%, my friend and I start to feel that the car starts to sway left and right, like the car is struggling to balance the power of the 2 rear wheels due to minute traction differences. I think a real LSD could really have helped.
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      03-03-2013, 08:17 AM   #5
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Put it on a dyno or it's just hearsay. The only difference between comfort and sport (stock) modes is throttle mapping. I can get more "power" out of my car just by pressing harder with my right foot.

Partial throttle driving with seat of the pants feedback is not an indicator of increased engine output. Any real gains are going to be at Wide Open Throttle (WOT) where maximum boost and output are realized.

Most of these simple tuner boxes modify signals (usually boost on a turbo engine) to the engineer computer. They reduce the boost signal to force the factory computer to produce more boost as it attempts to hit the maximum factory spec. Addition fuel and spark control are left up to the stock software to compensate for based on the existing feedback control systems. These mods assume the factory controls and fuel injectors can keep up with the increased demand due to the additional boost. If they can you get more power, if they cannot you get trouble.

I sincerely hope it's the former, but without before and after dyno results there's no way to be sure.

One test you could perform is taking a unbiased passenger along for a few 'before and after' timed runs from say 20mph, while passing a fixed marker, to another point at least 1/4 mile away - at WOT. Use an accurate stopwatch and have the passenger time the run from point A to point B. When you pass point A at 20mph, floor it. Let the car shift automatically. Don't get arrested. This will take launch out of the equation. Any significant reduction in time can be attributed to more WOT power as long as you do all your runs at basically the same climatic and road conditions. How MUCH more power could be calculated from the results, but a dynamometer run would be more accurate.

I am fairly certain the N63Tu develops more boost from the factory. If the TMC unit is simply "subtracting" 1 or 2 PSI from the signal, in theory you would get a similar total increase on top of the 445hp. However, now you're really asking the factory software and fuel system to do a lot more than it was originally programmed for.

In any case, good luck.
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      03-03-2013, 09:12 AM   #6
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I hear you. I haven't got a chance to do real dyno tests here (Just got it installed last night and Sunday here). Unofficial butt dyno feel will have to do for now
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      03-03-2013, 12:58 PM   #7
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Quote:
Originally Posted by mlai View Post
When, they only said similar gains as the N63. I am happy if it hits 500hp
whow!
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      03-03-2013, 01:03 PM   #8
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Quote:
Originally Posted by mlai View Post
Just went thru a test drive with the TMC tune on my 650i GC with a friend. Some quick 2cents comments:

1) Below 2000rpm, the gains are there but not very noticeable. Possible due to the fact that the 650iGC has more than enough low-end torque. My feeling is that if the low-end torque goes any higher than now with boost, the rear axle may have problem putting those torque down to the road......

2) Above 2000rpm, the gains are VERY noticeable. In comfort mode, there is a much firmer push from the back feeling when accelerating and response is fabulous as well. In sport mode, I can only describe it as a major kick in my butt! I did a pull all the way to 5500rpm and is nothing short of amazing!

3) Gas consumption? Well, I only had it since last night so a bit premature to draw conclusion yet. Let me revisit this after a few weeks.......

4) My feeling is that adding the TMC (or other tunes) to the 650i GC is great if one wanted more power to the car off the straight line but I don't think the 650i GC is lacking in the power department to begin with. I am now more concerned about the 650i GC control of such power. When stepping on throttle even at 75%, my friend and I start to feel that the car starts to sway left and right, like the car is struggling to balance the power of the 2 rear wheels due to minute traction differences. I think a real LSD could really have helped.
That might just made it to my todo list. I am still researching into X-Pipe, trying to find self-replaceable unit instead of permanent cut.
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      03-07-2013, 03:01 AM   #9
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Well.... First issue came up and I believe it is specific to my car configuration....

TMC tune is working well and got a boat load more power from my butt dyno. Yes, gains are not real until proven on dynos. But just so much fun driving the car now and I have other prove that there is a power gain (not so fun, though).

Problem is that with the power increase, when engine goes above 5K+ rpm, the rear-end gets really wobbly. I believe that the excess torque is too much for the IAS on my car to handle. I tested on the same stretch of the road, putting the pass-through plug on the cable and the car revs past 6K absolutely stable.

But with the tune at default position of 6, rear-end wobbles at 5k+rpm even on straight stretch....

So let me try detuning a bit and see......
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      03-09-2013, 01:41 AM   #10
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Quote:
Originally Posted by mlai View Post
Well.... First issue came up and I believe it is specific to my car configuration....

TMC tune is working well and got a boat load more power from my butt dyno. Yes, gains are not real until proven on dynos. But just so much fun driving the car now and I have other prove that there is a power gain (not so fun, though).

Problem is that with the power increase, when engine goes above 5K+ rpm, the rear-end gets really wobbly. I believe that the excess torque is too much for the IAS on my car to handle. I tested on the same stretch of the road, putting the pass-through plug on the cable and the car revs past 6K absolutely stable.

But with the tune at default position of 6, rear-end wobbles at 5k+rpm even on straight stretch....

So let me try detuning a bit and see......
Please keep updating, I am excited to hear the feedback.

My car is going through a series of drive train malfunction right now. I probably cannot do any mod to it until I know for sure it won't hiccup again to use warranty.
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      03-09-2013, 06:38 AM   #11
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Quote:
Originally Posted by mlai View Post
But with the tune at default position of 6, rear-end wobbles at 5k+rpm even on straight stretch....
Do you mean in first gear at WOT above 5k, or any gear at WOT above 5k, or any throttle position above 5k?
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      03-09-2013, 07:39 AM   #12
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Quote:
Originally Posted by Bönz View Post

Most of these simple tuner boxes modify signals (usually boost on a turbo engine) to the engineer computer. They reduce the boost signal to force the factory computer to produce more boost as it attempts to hit the maximum factory spec.
Bonz, always good to read your posts. I can tell you know what you are talking about.

Roadsta.
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      03-10-2013, 01:24 AM   #13
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Quote:
Originally Posted by Bönz View Post
Do you mean in first gear at WOT above 5k, or any gear at WOT above 5k, or any throttle position above 5k?
Not only in first gear. In 1st, 2nd, 3rd at least. And not even at WOT, just when rpm hit above 4.5k rpm with the tune at pos 6, rear end becomes unstable, even in a straight-line.
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      03-10-2013, 01:39 AM   #14
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Adjusted the tune position to 4 (map 4). I can still feel very very faint wobbles from the rear end but at much higher rpms 6-7k (almost max at WOT) at 2nd and 3rd. Not much chance to try higher gears at those rpms here in Hong Kong, without being completely irresponsible to myself and others....

However, the gas consumption as indicated by the onboard computer scared me to death. We are using metric units here and at tune 6, onboard computer indicated my average gas consumption was 23.6L/100km. At tune 4, the obc is showing 26.0L/100km.....

Granted, the most accurate consumption figures should be manually calculated from distance travelled and total amount of gas added to the car from the pump, but still, seeing that change of figures from obc after detuning the TMC kind of concerns me.......

The lost of performance from map 6 down to map 4 wasn't really noticeable here, but then, it was hardly stressed even at map 4.
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      03-10-2013, 02:32 AM   #15
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sound like a good horse gain for the buck
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      03-10-2013, 06:57 AM   #16
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Quote:
Originally Posted by mlai View Post
Not only in first gear. In 1st, 2nd, 3rd at least. And not even at WOT, just when rpm hit above 4.5k rpm with the tune at pos 6, rear end becomes unstable, even in a straight-line.
Are you sure it's the rear end? What you are describing sounds like it could be an engine induced vibration, perhaps felt as a rear end instability, which is why I asked the question. Whatever it is, it's not good. Keep the setting on the lower numbers. My fear is the factory fuel map cannot keep up with the over boost condition from the "tune" and you are forcing the engine into a lean condition. This is sensed by the O2 feedback loop and the ECM is doing what it can to compensate by adjusting spark, boost, fuel, etc. This could be the cause of the shake you feel.

These engines (without tune) produce nearly 100% of peak torque at WOT from as low as 1800 RPM. If your problem were torque induced rear end instability, you would feel it from much lower on the power band.

Personally, I would be wary of these low cost aftermarket systems. You spend over $100k (a lot more in Hong Kong) on a premium automobile and then want more cheap HP.

Quote:
Originally Posted by roadsta View Post
Bonz, always good to read your posts. I can tell you know what you are talking about.

Roadsta.
Thank you.
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      03-10-2013, 08:09 AM   #17
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Are you sure? It was not a vibration that we felt. The front was absolutely stable. The rear wobbles left and right which I need to correct via steering input!
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      03-10-2013, 09:42 AM   #18
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No I am not sure. I am speculating based on all the information you have provided.

Try this. On an open road where you have plenty of clearance and space and no other cars around, put the car in Sport plus and turn off all the nannies. You do this by holding the DSC button down for about 5 seconds until the "DSC Off" illuminates in the gauge cluster. Then go for it. With an open rear differential and no DSC or DTC to intervene, all you should do is burn rubber. The rear end will certainly want to come around (usually to the right) requiring steering input to correct. But the sensation should be of controlled oversteer, not an instability or "wobble" as you called it.

Based on my experience and automotive knowledge, it just seems unlikely that a little more torque would "overpower" the rear suspension and differential. It seems more likely that the TMC unit is messing up the electronics in your car. Then again, just my opinion. I could be wrong.
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      03-10-2013, 10:23 AM   #19
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Looks like the one way to find out is posting a vid with 0-60 + 1/4 mile time or dyno.
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      03-10-2013, 07:49 PM   #20
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Quote:
Originally Posted by Bönz View Post
No I am not sure. I am speculating based on all the information you have provided.

Try this. On an open road where you have plenty of clearance and space and no other cars around, put the car in Sport plus and turn off all the nannies. You do this by holding the DSC button down for about 5 seconds until the "DSC Off" illuminates in the gauge cluster. Then go for it. With an open rear differential and no DSC or DTC to intervene, all you should do is burn rubber. The rear end will certainly want to come around (usually to the right) requiring steering input to correct. But the sensation should be of controlled oversteer, not an instability or "wobble" as you called it.

Based on my experience and automotive knowledge, it just seems unlikely that a little more torque would "overpower" the rear suspension and differential. It seems more likely that the TMC unit is messing up the electronics in your car. Then again, just my opinion. I could be wrong.
I know I mentioned differential/rear suspension initially, but please do read my follow on comments. The car is equipped with IAS (4 wheel steering) and I subsequently think the the extra torque is overpowering that system which controls the turning of the rear wheels +/- 3 degrees. If that system is overpowered and allowed the rear wheels to move, that will cause the rear-end wobbling that my friend and I feel.
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Last edited by mlai; 03-10-2013 at 08:34 PM.
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      03-10-2013, 07:50 PM   #21
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Originally Posted by JNoSol View Post
Looks like the one way to find out is posting a vid with 0-60 + 1/4 mile time or dyno.
Yeah I know.... A bit busy being single parent with 2 girls and to make money at the moment..... Will try to get around to it on my vacation
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      03-11-2013, 11:01 AM   #22
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Quote:
Originally Posted by mlai View Post
I know I mentioned differential/rear suspension initially, but please do read my follow on comments. The car is equipped with IAS (4 wheel steering) and I subsequently think the the extra torque is overpowering that system which controls the turning of the rear wheels +/- 3 degrees. If that system is overpowered and allowed the rear wheels to move, that will cause the rear-end wobbling that my friend and I feel.
Perhaps you are correct. But keep in mind, the rear IAS system is built to handle the lateral load of a 4500lb car cornering at nearly 1g, while under power, without being "overpowered". I would certianly hope it could stand up to a few extra lb-ft of twist in a straight line, without exibiting would could only be classified as torque-steer.
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