[bigdnno98]

Originally Posted by doug@frankenturbo

After the false start with an incompatible OBD cable, we're on track now with the MHD Android application. To start, I went with what's cheap...uh, free. I downloaded the MHD flash files linked by BMS in this thread and found the appropriate one for the car's IJE0S version type. After switching the JB4 into Map 0 for passive mode, I loaded the file labeled "Pump" onto the car's DME.




After about a half-hour of flashing, the car was ready to try out. Because the previous logging data showed a shortfall in actual boost, I wanted to try upping the boost command level even higher. Perhaps "doubling down" on the commands might tease a bit more solenoid duty from the control system. Here are the logs of this new configuration:




The standout data points are boost and ignition timing. This latest version of a JB4 Map 6 is clearly asking for more boost than the hardware can develop. And the ignition timing map is very clean with zero corrections. Here are side-by-sides of the Pump Gas map's data compared to those from the stock DME.




So overall the new DME mapping is resulting in better-looking data. And the car feels plenty quick through the 4200-6500rpm sweep. In fact, it's at its fastest level yet:




I was interested, though, in how the new timing map might impact the low end. Reduced timing before 3000rpms is oftentimes good for spooling up the turbos. But it costs torque development. Would that show up in the Time-to-Speed metric?




Yes it does. The car's sub-3000rpm performance has taken a hit. But the new calibration is unmistakably making up for it in the midrange. And the timing pull that was nettling the DME on stock mapping is now eradicated.

Next up: more hardware changes. It's time to explore exhaust mods.

Great work. Keep it up. Are you going to post info on the hardware you're using? Links and prices?

[patsbimmer1]

Excellent info! I have a lot of friends in the VAG scene and am very familiar with your products. It's great for me to read through your development process. You often don't get a chance to see why something is done a certain way. Nice job!

[PORTMOODY]

very well documented. People can read years worth of threads or just this one. Looking forward to the updates.

[bradsm87]

When are you guys hoping to fit catless downpipes and measure exhaust backpressure?

[doug@frankenturbo]

Exhaust system mods underway. We went with VRSF 3" units. They are inexpensive, well-made & install just as they should. In other words, they are a great value for this kind of mod.

They didn't stay intact for long, however. Bungs for EGTs and back-pressures got added before the installation.






Side-by-sides






Installation








EGT probe post-turbine




With the primary cats gone there's no longer any rationale for monitoring temps at that location. So the probe now lives post-turbine... until the first modified turbos get fitted.

[sirdaft1]

Originally Posted by doug@frankenturbo

Exhaust system mods underway. We went with VRSF 3" units. They are inexpensive, well-made & install just as they should. In other words, they are a great value for this kind of mod.

They didn't stay intact for long, however. Bungs for EGTs and back-pressures got added before the installation.






Side-by-sides






Installation








EGT probe post-turbine




With the primary cats gone there's no longer any rationale for monitoring temps at that location. So the probe now lives post-turbine... until the first modified turbos get fitted.

Those DP's really open up the exhaust flow. One of the best bang for the buck mods for the N54. Looking forward to seeing the data

[VinceCarbone]

Originally Posted by Heel Toe

Nobody is reaching 500whp on stock turbos on a tune they can actually drive everyday that won't blow the turbos in 1k miles. 460whp is really the upper limit for a daily map.

Ignoance at its finest.

[VinceCarbone]

I already see a ton of problems. Cant wait to see the final "product"

[RobertRichy]

Doug- thanks for taking the time to document and share. I'm learning quite a bit just from observing.

[///Mposter]

Originally Posted by VinceCarbone

Ignoance at its finest.

Which is why you have a reputation of 3 and are hated on the other forums. I really do not care if it was me or the other quote you are talking about. If you have a problem with me , the other person, or what Doug has brought to the table, then you can just leave the thread. Take your negative views of the Turbo kits you do not like and put them where the sun doesn't shine.
Good day sir ...good day.

[Glennyd]

Good work Doug, some people justify there unhappiness by just shitting on everything around them. All we can do is smile and pray for those people . Keep up the good work

[Torgus]

Originally Posted by VinceCarbone

I already see a ton of problems. Cant wait to see the final "product"

Go away troll, no one likes you.

[sirdaft1]

Originally Posted by ///Mposter

Which is why you have a reputation of 3 and are hated on the other forums. I really do not care if it was me or the other quote you are talking about. If you have a problem with me , the other person, or what Doug has brought to the table, then you can just leave the thread. Take your negative views of the Turbo kits you do not like and put them where the sun doesn't shine.
Good day sir ...good day.

I took it as him quoting Heel Toe who said that no one is hitting 500whp on stock snails. In which case, I think we're on the edge of seeing that become more and more commonplace with the new inlet/outlet offerings. I could be wrong though.

[ThugzZ BunnY]

I am loving this thread. will definitely be watching very closely now that my turbo seals are going out.

[doug@frankenturbo]

Before startup I'd feared the modified exhaust system would sound awful. Especially during the warm-up cycle. But after lowering the lift and turning it over I was happy. The exhaust note was not ruined. In fact it seemed to be simply a louder version of its old self. That suited me fine, so I grabbed the laptop and took the car straight to our top-secret testing spot. At wide open throttle the new system again presented itself attractively: a slightly more pronounced throatiness, but no rasp or sharpness.

So what of the exhaust system back-pressures? Did the removal of the primary cats change the readings? On the stock system the pressures went above 7psi. But with the upgraded down-pipes, we now have this:




Unmistakably the post-turbine pressures are lower. The exhaust system flows measurably better with those primary cats removed. But...here's the thing: the data logs aren't showing much of any benefit. Here are the principal data points:




And here are those same measurements weighed against those from the full exhaust system:




Air/fuel, ignition advance & boost duty are all identical between the pulls. And intake air temperatures are slightly in favor of the most recent pull. Nevertheless, actual boost falls off just as sharply as before. The other data point to the same thing. here is the time-to-speed chart:




But the most illustrative of them all is the 4200-6500rpm sweep. The time calculation for that comes in like so:



Exactly the same as the stock exhaust system delivered. In my view, for any hope of gains made by modifying the exhaust, ALL of the cats have to be removed.

We'll test for that next.

[bigdnno98]

Originally Posted by doug@frankenturbo

Before startup I'd feared the modified exhaust system would sound awful. Especially during the warm-up cycle. But after lowering the lift and turning it over I was happy. The exhaust note was not ruined. In fact it seemed to be simply a louder version of its old self. That suited me fine, so I grabbed the laptop and took the car straight to our top-secret testing spot. At wide open throttle the new system again presented itself attractively: a slightly more pronounced throatiness, but no rasp or sharpness.

So what of the exhaust system back-pressures? Did the removal of the primary cats change the readings? On the stock system the pressures went above 7psi. But with the upgraded down-pipes, we now have this:




Unmistakably the post-turbine pressures are lower. The exhaust system flows measurably better with those primary cats removed. But...here's the thing: the data logs aren't showing much of any benefit. Here are the principal data points:




And here are those same measurements weighed against those from the full exhaust system:




Air/fuel, ignition advance & boost duty are all identical between the pulls. And intake air temperatures are slightly in favor of the most recent pull. Nevertheless, actual boost falls off just as sharply as before. The other data point to the same thing. here is the time-to-speed chart:




But the most illustrative of them all is the 4200-6500rpm sweep. The time calculation for that comes in like so:



Exactly the same as the stock exhaust system delivered. In my view, for any hope of gains made by modifying the exhaust, ALL of the cats have to be removed.

We'll test for that next.

In for that test. It's been assumed for a long time that gains from removing the secondary cats weren't enough to justify the rasp that it caused.

[sudo4re]

I for one, am glad that Doug is taking the time to test out these "upgrades". What happened to the 15-20 extra hp gain from just swapping in a set of catless kitties? Don't get me wrong, I'm running these kitties as well and frankly, I'm disappointed by Doug's results but at least my exhaust sounds meaner than before lol.

Looking forward to more testings and results

[c131frdave]

Thank you for making this thread. As a brand new 335i owner, I find it very informative and helpful. It's nice to see a methodic study of the car from scratch. The exhaust issue you've found sort of confirms my initial theory with the downpipe you chose to use as well. However, your readings might be misleading- if your sensor is in the 3" section of the pipe, Bernoulli's Principle dictates that the pressure here will be higher than if it were measured at the exit of the turbo, which I believe is 2.5". I'd be interested in a test with a pipe that was of consistent diameter from the turbo to further back in the system where the exhaust gas temperatures begin to fall off.

[mwahlert]

Originally Posted by doug@frankenturbo

Exactly the same as the stock exhaust system delivered. In my view, for any hope of gains made by modifying the exhaust, ALL of the cats have to be removed.

We'll test for that next.

Fascinating work.
Since you already have MHD, it would be interesting to see the time comparisons in this state of hardware - backend flash/JB4 vs Stage 2 MHD flash.

Edit: I've been watching this platform evolve since late 07. It is refreshing to see someone new to the platform validate for himself what is considered "truth".

[BMOEW]

Great work! But why does everyone keep quoting every post with pics. Just useless and repetitive! Lol

[V8bait]

You do realize the dme targets load, and flash tune/jb4 alike are effected by this right? So you measured a 2+psi drop in exhaust pressures, which is nice considering it's on both banks (what is that a 30% reduction?), and you now notice a drop in boost at the same wgdc due to an increase in airflow through the motor. You just proved what everybody already knows, downpipes make the same power at lower boost. Post turbine changes are different than pre turbine. Post turbine increase ve and make the turbos work harder, pre turbine help efficiency and reduce pressure drop.

[doug@frankenturbo]

Secondary cats are now deleted, replaced with a pair of Vibrant resonators.








Resulting data in a bit.