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Anyone used the Renntech tuner on Their newer generation GLA45? If so what was your experience? I’m talking about the 375hp version of the GLA? I know this model is still under warrantee so some may be apprehensive.
 

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Yeah, good question

I have a 19 as well and come to the platform from a 500ish mazdaspeed6 which is still on stock air con, ;-)

so yeah, I so wanna fuq with it, but just spent a day with a loaner, while getting my 20K prepay done, (4200miles on the clock, but, warranty, yeah?)

As you arre proly aware, there have been some itereations to the engine, and the first did not use a DV

our 19's use an electronically controlled DV

Most aftermarket DV are 'kits' involving a vaccum "T" to run a conventional DV

I personnally would not leave that kind of control on the table, IE give up the ability to control the DV independently

whew, so, I was thinking tune, but the warranty...so not gonna do it. Later tho, yeah, When that time comes, unless the tune was developed on a 375 (with DV), on a 4 wheel dyno, I would not use it. and I think many come from 2015's so, caveat emptor

Also, this sweet ass tranny, has a brain, and feelings, so if you twist on the input shaft to hard, the trans, will tell the ECU to stop doing that. negating your efforts
 

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Discussion Starter #3
Yeah, good question

I have a 19 as well and come to the platform from a 500ish mazdaspeed6 which is still on stock air con, ;-)

so yeah, I so wanna fuq with it, but just spent a day with a loaner, while getting my 20K prepay done, (4200miles on the clock, but, warranty, yeah?)

As you arre proly aware, there have been some itereations to the engine, and the first did not use a DV

our 19's use an electronically controlled DV

Most aftermarket DV are 'kits' involving a vaccum "T" to run a conventional DV

I personnally would not leave that kind of control on the table, IE give up the ability to control the DV independently

whew, so, I was thinking tune, but the warranty...so not gonna do it. Later tho, yeah, When that time comes, unless the tune was developed on a 375 (with DV), on a 4 wheel dyno, I would not use it. and I think many come from 2015's so, caveat emptor

Also, this sweet ass tranny, has a brain, and feelings, so if you twist on the input shaft to hard, the trans, will tell the ECU to stop doing that. negating your efforts
Very interesting and thank you for that I had no idea that the 2019 went to an electronic DV. What did the earlier models use? Yes the Renntech tuner was designed for the original 45 I’m not sure why they haven’t bothered fine tuning one for the 2019 model but I think I will ask them. Probably supply and demand since 2019 would still be under warrantee.
 

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Not positive, but I think, 16.. for sure 17-19.

I have a turbosmart EDV on the shelf, the "also fits" list for the PN# is good for a chuckle..
I'm assuming that the oem valve holds 2or3 lbs over stock, so post tune the only advantage of the TS will be faster response time, full recir won't likely sound loads better, so
 

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The Bypass valves, or Diverter Valves, recirculate the already metered air. By blowing that air out, with a blow-off valve, you're getting rid of already metered air and that's just not a good thing, it affects the AFR.
In addition to this, even back in the days when the bypass valve was only vacuum controlled, built in were additional features:
Bypassing under vacuum operation, meaning with the car running aspirated, the air can skip the intercooler and come directly to the throttle body, or close to.
Then it has idle support functions, etc.
Now with electronic control, this can do things like act when the car is in reverse and who knows what else,

On the other hand, a bypass valve can be made to be noisy, without discarding any air to the exterior.
I had a Synapse in full bypass mode, on a different car, with no air being lost and it was quite nicely noisy. On the other hand, switching the intake tube post turbo to a hard steel one, amplifies air noise and now you can hear the air rushing into the turbo.
Similarly, if there is a way of witching any tubing by the EBPV to metal, this may provide exactly the noise people want.
 

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I have a '15 and have been planning to buy this tuner for a year or so. I have not due to feeling guilty of a purchase like this and instead sending money to my local food banks and what not to help others during these times. I do not mean this statement as anything other than an explanation why I have not bought this yet.

The '15 did not have a BOV, I have an aftermarket Weistec mechanical unit installed, works as it should and has little noise. Also an aftermarket AMS high flow air filter. The difference between the earlier model and a '19-20 is minimal, I've said this in prior posts. 20hp and 18/lb ft. There is no indication boost was raised, it's simply fine tuning the trans (which it needed, though I understand mine and it works a bit brutally at times), and likely messing with some cam specs, fuel/air delivery.

So would this unit work on a newer version? Call them up, ask about programming changes and how they dealt with that for your newer version. I bet they have been updating their program to recognize the year and deliver the proper map. It likely would not be all that different from a newer version. Would you have any more HP than what they provided given they tested on an earlier???? Honestly I take all these numbers with a grain of salt and figure my numbers will be below what they say. End of day for me is that I would love to have a 2.0 delivering 410HP and about 400 lb/ft.
 

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You should log the car, with a high flow air filter. The mapping of the car may need to be adjusted.
Your first indication would have to come from an OBD2 reader. What are the long term trims?
Adding a "tuner" on top of mods that the tuner is not programmed to know anything about, is a bad idea.

As far as how the factory got extra HP, Xentry can show the boost value, I'm going to try to see if an Autel can as well, its more compact. One of these 2 can probably log it too.
But the factory could have changed hardware AND software. It may be that the difference in numbers is somewhat small, even though the difference in 0-60 is rather noticeable, but with factory upgrades, they tend to obtain small results from large changes. This is how you have increases in power, but retain that reliability that you're warrantying, as a manufacturer.

Look to what it took to go from 375 HP for 408 HP (416 PS), a 33 HP increase:
Complete redesign of the architecture of the engine, turbo is now at the back, intake is now at the front, they basically turned the engine around, for 33 HP.

As far as potential changes, I think that for the new BPV, the compressor cover had to be redesigned. Once that door is open and MB has to pay Triple K or Garrett to recast their compressor cover, then changing the trim of the compressor impeller wheel comes in as peanuts, might as well pay to do that too, so, you never know..
Edit:
They changed the exhaust camshaft and tune.
 

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Look to what it took to go from 375 HP for 408 HP (416 PS), a 33 HP increase:
Complete redesign of the architecture of the engine, turbo is now at the back, intake is now at the front, they basically turned the engine around, for 33 HP.

As far as potential changes, I think that for the new BPV, the compressor cover had to be redesigned. Once that door is open and MB has to pay Triple K or Garrett to recast their compressor cover, then changing the trim of the compressor impeller wheel comes in as peanuts, might as well pay to do that too, so, you never know..
Edit:
They changed the exhaust camshaft and tune.
Dunno where I saw this, so do not state as fact, But aside from the above, the added some suppemental fueling.

obviously its supplied by the stock ITFP so, no magic knock bullet, but getting a daily driver turbo to blow hard to redline, usually involves going pig rich to control the flamethrower the little turbo turns into at that end of the curve.( and yeah, the wheel may have grown a couple mil)
 

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It makes sense that the OEM tune should be pig rich, this is to be expected. They work on ignition and cam timing and boost comes in after the fact, kinda opposite than the aftermarket tuners.
Tuning by timing with pig rich fueling is how you can roll out an engine with a warranty like the factory does. It's said that it takes hyper-accurate knock knowledge that the factory gets from advanced simulations and from... breaking engines through testing.
 

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AMG has a building dedicated to breaking engines. Every new design goes through many many months of dyno operation with variable loads and temperature shocks. Oil changes and analysis allows better evaluation of maintenance scheduling and warns of early problems. Add to that end of testing tear down and wear investigations. It is impressive!!!

And to sweeten the pot, the town gets electrical power from these test stations.
 

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It makes sense that the OEM tune should be pig rich, this is to be expected. They work on ignition and cam timing and boost comes in after the fact, kinda opposite than the aftermarket tuners.
Tuning by timing with pig rich fueling is how you can roll out an engine with a warranty like the factory does. It's said that it takes hyper-accurate knock knowledge that the factory gets from advanced simulations and from... breaking engines through testing.
yeah, stuff like this
 
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