[DrRobert]

In an earlier thread, I posted dyno results from Pure Stage 1 and Stage 2 turbos on 91 octane California gas, and expressed my disappointment at the gains I saw going from Stage 1 to Stage 2 turbo. At that time it was not clear to me if the underwhelming gains were because I still had the OEM cat or because of the crappy 91 octane gas we have here in CA, but I was determined to figure it out. Since I have custom flash tuning by PTF I decided to retune for different fuel blends followed by a new DP, but that process has taken WAAAY longer than expected due to PTF's preoccupation with the development of their new F30 tuning platform and slow responses to requests for map updates since early summer. But I finally have a few results to post for you guys, even though this is still a work in progress. (My mods are listed in the garage list link to the left, if you are interested.)

First I repeated the dyno on 91 octane with the OEM cat to make sure my original Stage 2 dyno was accurate. It was pretty close to what I had posted previously as this first graph shows. Red is the dyno posted in the earlier thread, blue is the repeat dyno to confirm.


Next I spent a long time working with Dzenno trying to tune the car for E30 and higher percentage E85 blends, which turned out to be a total pain in the ass. I installed a Fuel-It stage 2 LPFP but it kept giving me warning lights on the dash that I did not like and could not get rid of. I ended up uninstalling the LPFP and opting for an E30 tune with the OEM LPFP, which others have reported success with but which did not work for me. I did manage to get a clean dyno on E30 but Dzenno could not get rid of the misfires I kept getting on the road, so I abandoned E85 blends in frustration. Here is the dyno though. Blue is 91 octane, red is E30:


I also have access to 101 octane unleaded race fuel (VP 101), which was my only other fuel alternative as I don't want to mess with meth kits or octane boosters. It is expensive though so I ran a 50:50 blend with 91 octane to make 96 octane. Here is the dyno after Dzenno retuned for this fuel blend.


Finally I dealt with the cat. I think most of you would have done this before upgrading the turbo (and you would have been right to do so IMO), but before all of this I was reluctant to ditch the OEM cat as I did not want to deal with the noise, smell and hassle of passing CA smog checks. I still did not want to go catless, and after a lot of research I concluded that an HJS cat was my best option. Unfortunately nobody makes a catted DP with HJS cat for E-series N55s, so I had one retrofitted into the OEM DP by Fabspeed Motorsport. They did a great job but I did not like the increased exhaust volume so I added a Magnaflow 4x9 straight through muffler to the midpipes, which quieted it down nicely. Dzenno then retuned the car for the new cat on 91 octane. Here are two runs from the dyno session on that map.
.

The obvious next step is to tune for 96 octane with the HJS cat. I have already started that process but there is no telling how long it will take for PTF to finish it. I might also consider another attempt at upgrading the LPFP and adding TBI or PI later on after the CPO warranty expires. But actually I am now very happy with how the car is driving, and I am having a blast driving it as my DD in its current state on crappy CA 91 octane gas.

[houtan]

Thanks for the update. Hopefully MHD will provide the tuning tools missing in Cobb so you can get your car running on e85 blends. I heard Cobb may be updating the accessport with new tables as well.

If you put the stage 2 pump back in, you may want to look into having your car coded to prevent the cel you were seeing from coming back. Here is the link: http://www.n54tech.com/forums/showthread.php?t=42012

[AirbusPilot]

Frustrating.

I think at this point, I'd put an uncatted DP with the smog check fix and live with the minor fumes smell.

[DrRobert]

Originally Posted by houtan

Thanks for the update. Hopefully MHD will provide the tuning tools missing in Cobb so you can get your car running on e85 blends. I heard Cobb may be updating the accessport with new tables as well.

If you put the stage 2 pump back in, you may want to look into having your car coded to prevent the cel you were seeing from coming back. Here is the link: http://www.n54tech.com/forums/showthread.php?t=42012

Wow thanks for that link houtan. That might come in handy some day. And yes, I am following the MHD development closely, hoping it solves some of the frustrations of flash tuning via Cobb.

[DrRobert]

Originally Posted by AirbusPilot

Frustrating.

I think at this point, I'd put an uncatted DP with the smog check fix and live with the minor fumes smell.

Yes, very frustrating. I posted this to hopefully help others avoid some of the frustrations I went through.

I like my HJS cat. For me it is a keeper, unless any problems arise because of it in the future. I know many others would prefer a catless DP, but not me.

[shirtpants_]

Good to see you finally got rid of the stock cats. Even on 91 I was still expecting to see higher numbers. At least the power doesn't drop at 5500 like the stock turbo though, that's the best part.

At least you can get PTF to respond to you. I've sent around 4 or 5 emails to them regarding my tune since July and haven't gotten a response to any of them...

[MiamiM3]

Robert,

Really looking forward to the N55 MHD. Hopefully it will open up some opportunities for all of us poor bastards that have to run California's crappy 91 oct. I am also looking forward to eliminating the cold start cycle.

[DrRobert]

Originally Posted by shirtpants_

Good to see you finally got rid of the stock cats. Even on 91 I was still expecting to see higher numbers. At least the power doesn't drop at 5500 like the stock turbo though, that's the best part.

At least you can get PTF to respond to you. I've sent around 4 or 5 emails to them regarding my tune since July and haven't gotten a response to any of them...

The new cat really helped a lot with turbo lag too. That's the other best part.

[houtan]

Any cel with the high flow cat? Have you had a chance to see if all of your monitors are set to ready to Las cali smog?

[DrRobert]

Originally Posted by houtan

Any cel with the high flow cat? Have you had a chance to see if all of your monitors are set to ready to Las cali smog?

No cel. I bought the tool to check ready state but haven't checked it yet - I thought I was due for a smog check this year but then it turned out I wasnt. I could check it for you if you want.

[WedgePerformance]

Think you'll be really happy with MHD N55. I bought a 2012 135i MSport DCT just so I can develop base maps on a DCT car because of all the issues we have seen in the past with tuning DCT cars with COBB.

Car is completely stock on 92 oct. I have all the mods sitting waiting to be installed. Already spoke with PURE about a Stage 2 also. Car is a blast to drive.

[DrRobert]

Originally Posted by WedgePerformance

Think you'll be really happy with MHD N55. I bought a 2012 135i MSport DCT just so I can develop base maps on a DCT car because of all the issues we have seen in the past with tuning DCT cars with COBB.

Car is completely stock on 92 oct. I have all the mods sitting waiting to be installed. Already spoke with PURE about a Stage 2 also. Car is a blast to drive.

Yes, I saw your post about that in the other thread. I'm thinking I might have to try a custom MHD flash tune if all the pre-release hype about it turns out to be true. Waiting patiently...

[asrautox]

Just a thought with respect to misfires and E85 use. I've found that misfires seem to become an issue depending on which base tune I start with (Stage 1 vs. Stage 2 OTS). This would lead me to believe that there are some parameters that Cobb changes between the two that we do not have access to in the ATR tables. I was experiencing bad misfiring on E40 when I went catless. I changed plugs, upgraded my LPFP, raised my AFR's, everything. I was frustrated, so I went back to my stage 1 map and just unchecked the Cat code. Voila, no more misfires. I'm now running the same load, timing, AFR, boost, etc. With no more misfires to report. Might be worth a look to find out which map they start with..

[DrRobert]

Originally Posted by asrautox

Just a thought with respect to misfires and E85 use. I've found that misfires seem to become an issue depending on which base tune I start with (Stage 1 vs. Stage 2 OTS). This would lead me to believe that there are some parameters that Cobb changes between the two that we do not have access to in the ATR tables. I was experiencing bad misfiring on E40 when I went catless. I changed plugs, upgraded my LPFP, raised my AFR's, everything. I was frustrated, so I went back to my stage 1 map and just unchecked the Cat code. Voila, no more misfires. I'm now running the same load, timing, AFR, boost, etc. With no more misfires to report. Might be worth a look to find out which map they start with..

Yes but I was using a custom map, not the OTS maps. The map that PTF started with for E85 blends was my custom map for 91 octane and the mods I had at that time. We were already a long way away from the OTS maps by that time.

[asrautox]

Originally Posted by DrRobert

Yes but I was using a custom map, not the OTS maps. The map that PTF started with for E85 blends was my custom map for 91 octane and the mods I had at that time. We were already a long way away from the OTS maps by that time.

Understood, but you might want to ask what they started with for their custom maps. They might not say, but it's worth the question. It's quite easy to copy and paste your current settings onto a Stage 1 OTS map. I also had no misfires on straight 91 regardless of where I started. It was only after going to E40 from the Stage 2 map that I ran into issues.

[DrRobert]

Originally Posted by asrautox

Understood, but you might want to ask what they started with for their custom maps. They might not say, but it's worth the question. It's quite easy to copy and paste your current settings onto a Stage 1 OTS map. I also had no misfires on straight 91 regardless of where I started. It was only after going to E40 from the Stage 2 map that I ran into issues.

What LPFP did you have at that time?

[asrautox]

Boost Concepts (same pump as the Fuel-it Stage 2). Still have it. I get the caution light occasionally which doesn't really bug me that much, but there is a Winkfp fix for it that I plan to use: http://www.n54tech.com/forums/showth...l+pump+current

[DrRobert]

Originally Posted by asrautox

Boost Concepts (same pump as the Fuel-it Stage 2). Still have it. I get the caution light occasionally which doesn't really bug me that much, but there is a Winkfp fix for it that I plan to use: http://www.n54tech.com/forums/showth...l+pump+current

Hmm. That is interesting. The trouble is that PTF is not responding to emails so I can't ask them your question. I'm still waiting for a map update for my 96 octane tune, and its been a month since I sent them the logs. I would like to know though. Since houtan posted that same link to the coding fix for the LPFP warning light I am considering reinstalling an upgraded LPFP, as the E30 dyno I posted above was better than the 96 octane dyno, and E85 is a lot cheaper than 101 octane race gas. I'd hate to go through all of that and still be dealing with misfires though.

Does anyone know misfiring on E85 blends is less of an issue with MHD than it is with Cobb tuning for E-series N55s?

[JETmn]

Hopefully you find the power. You are definitely down from where you should be. I know every dyno is different, but dynojets are close.

[asrautox]

The LPFP did not solve any of my misfire issues. Your story may be different however, since you're on the PS2 and are likely close to the fueling limit. My issues only went away when I changed tunes.

[houtan]

Won't know for sure about mhd until it is actually released but the hope is additional tables will be available that will stop the misfires from happening.

[DrRobert]

Originally Posted by JETmn

Hopefully you find the power. You are definitely down from where you should be. I know every dyno is different, but dynojets are close.

My dyno guy calls his Dynojet "the heartbreaker" because he says it tends to read lower than other dynos (he didn't say by how much). I asked him if it needed calibration or something but he said no, they're all a little different.