The old cut up manifold into trumpets idea

[rjahl]

Originally Posted by Dru128m

Bob is aware of the headers, and the 02 sensors are just downstream of the collector. Car ran fine with the headers before when the stock intake was still installed.

There was a bit of revelation yesterday. I took her out for some exercise, still cuts fuel under partial throttle around 4500k, but I mashed it to the floor just to try a proper 3rd gear pull and she ran up all the way no problems! Some data still looks off, but it's promising.

I did what I could to increase the log sample rate and sent it off to Bob, see what happens from here.

https://drive.google.com/file/d/1ARC...w?usp=drivesdk

I was thinking a little more about your tune and it's not a simple No Maf with headers tune.

With the throttle body removed, no air flow signal (MAF) and no manifold pressure signal (MAP), Bob has no way of knowing how much air flow is passing through the motor at low load. All of the low load stock maps were based on some throttle body interaction. Stock High load and full load map data will be really close as the throttle body is usually fully open under load. The problem is low load.

Without good data from you or some other test engine, Bob can do little more than take educated guesses.

If his calculation are wrong, the fuel mixtures will be off and the DME will correct with fuel trims. To some extent this will mess with the engine load calculations as well. Without the sensors the engine performance modeling calculations will he's based on assumed airflow data.

In short, get Bob good data and he should be able to sort out your tune.

Hassmachine has probably put a good deal of thought into these problems as well.

[Dru128m]

I'll get Bob any kind of data he wants all he needs to do is say the word, he said torque pro, so I did. I knew this tune would be tricky to nail, cuz it's basically shooting in the dark. I have confidence in Bob, he says jump, I'll ask how high. I still feel foolish, not noticing the substantial difference between partial and full throttle operations. I need to up my test driver game. Hopefully Bob gets this new data Monday morning and we're back to game on.

[dmytro98]

Any updates? Been following this thread closely as nobody else seems to be trying anything new

[Dru128m]

Ok, currently.
Start up is a trick, engine starts and idle is quite rough and lumpy, if left on its own DME eventually figures it out once the O2 sensors come online. Normally I'll put in some throttle raise rpms to around 2k where it will run smooth for 20 seconds or so then I'll slowly back it down to idle. Sometimes it takes a try or two before it idles smooth.
In town driving (1000-4000rpm) is not bad at all. Once you realize it doesn't care for 0-15% throttle and get a little heavier with your foot, it loves it, and drives pretty normal. I certainly don't feel any loss of torque, it will break the rears loose easier now than at any point previously.
Fun driving (4000-7700rpm) unfortunately is where I can't really play right now. Any throttle less than 90% above 4k and it just cuts fuel and goes lean, that's our current hiccup. It has ran there on previous tune revision and was glorious.
WOT throttle pulls are good. If I'm under 4k I can bury the throttle and it will sing all the way up. It pulls hard all the way and the only problem is now I'm going too fast.
A few more bugs and a dyno session and I'd say we're there. With that being said, the final 10% is always the hardest. I think that's where we're at.

[///Makis]

Originally Posted by Dru128m

Ok, currently.
Start up is a trick, engine starts and idle is quite rough and lumpy, if left on its own DME eventually figures it out once the O2 sensors come online. Normally I'll put in some throttle raise rpms to around 2k where it will run smooth for 20 seconds or so then I'll slowly back it down to idle. Sometimes it takes a try or two before it idles smooth.
In town driving (1000-4000rpm) is not bad at all. Once you realize it doesn't care for 0-15% throttle and get a little heavier with your foot, it loves it, and drives pretty normal. I certainly don't feel any loss of torque, it will break the rears loose easier now than at any point previously.
Fun driving (4000-7700rpm) unfortunately is where I can't really play right now. Any throttle less than 90% above 4k and it just cuts fuel and goes lean, that's our current hiccup. It has ran there on previous tune revision and was glorious.
WOT throttle pulls are good. If I'm under 4k I can bury the throttle and it will sing all the way up. It pulls hard all the way and the only problem is now I'm going too fast.
A few more bugs and a dyno session and I'd say we're there. With that being said, the final 10% is always the hardest. I think that's where we're at.

So just to be clear,

Are you saying that above 4K rpms at 100% throttle it doesn't cut fuel?

But if you're above 4k rpms and moderate throttle it does cut fuel?

If so that seems a bit bizarre.

When you removed your intake manifold and put the cut up one, what did you do with the mass airflow sensor?

Was that coded out? Or installed elsewhere on the modified manifold?

Also how did you route the pcv / ccv or is that vent to atmosphere?

I've been following this thread as well but I don't recall if this was mentioned before.

[rjahl]

Originally Posted by ///Makis

So just to be clear,

Are you saying that above 4K rpms at 100% throttle it doesn't cut fuel?

But if you're above 4k rpms and moderate throttle it does cut fuel?

If so that seems a bit bizarre.

When you removed your intake manifold and put the cut up one, what did you do with the mass airflow sensor?

Was that coded out? Or installed elsewhere on the modified manifold?

Also how did you route the pcv / ccv or is that vent to atmosphere?

I've been following this thread as well but I don't recall if this was mentioned before.

I've looked at his logs, It's not cuttings fuel it's just having to add more fuel then the engine management model think's it should. Once the fuel trim exceeds a certain value the DME throws a fault.

Seems like the full load air flow maps are probably close but he having a hard time with partial loads. This is when the standard stock air flow maps would be way off from his actual. No throttle body to buils intake manifold vacuum

With no MAF sensor and no MAP sensor, He needs to create his own expected airflow maps or his fuel trim will always be way off.

[///Makis]

Originally Posted by rjahl

I've looked at his logs, It's not cuttings fuel it's just having to add more fuel then the engine management model think's it should. Once the fuel trim exceeds a certain value the DME throws a fault.

Seems like the full load air flow maps are probably close but he having a hard time with partial loads. This is when the standard stock air flow maps would be way off from his actual. No throttle body to buils intake manifold vacuum

With no MAF sensor and no MAP sensor, He needs to create his own expected airflow maps or his fuel trim will always be way off.

Hey bud thanks for your reply.

And that makes a lot more sense.

But I thought the throttle body on the n52 always remained open (and ultimately did nothing) provided the eccentric shaft motor and vanos and o2 sensors I guess were working correctly no?

Would it have been easier for op to have somehow integrated the maf sensor so the tuner could have a slightly more dynamic map? Or at least another variable to go off of? Or does it not really matter because you can get away with a closed loop type of tune?

I should mention I have ultimately 0 experience tuning cars but have read and watched some videos so I have a basic understanding of it albeit primitive.


Pleased to hear

[Dru128m]

There are definitely easier ways to make more hp from your n52. I've never said this was a good idea, I just had to try. The allure of opening my hood to a row of ITB trumpets was just too strong. Not mention the noise. Bob is basically trying to tune this car with handcuffs on, in the dark, while underwater, so the fact I can drive it down the street is impressive enough. Bob's a busy guy and I have no doubt we'll get this done.

[hoveringuy]

For what it's worth, this is my N52 with S54 headers, N54 intake and a throttle body, otherwise no other changes.
I tried running without the throttle body but couldn't get it to run smooth enough to satisfy my OCD, particularly down low in the cruise regimes, although it ripped up top and at WOT. The engine model in the DME just wasn't close enough. With LOTS dyno time that could have been resolved but there's no compromise made with the MAF.
The dyno plots show MAFless vs MAF, and the MAF filled-in the bottom end nicely and just runs smoother all around.
It actually makes a little more power but something about the rate of acceleration on the inertia dyno related to the predictive rev limiter starts pulling power right after 7000.

[awhc]

Did you need to do any modifications to the S54 headers?

[hoveringuy]

Originally Posted by awhc

Did you need to do any modifications to the S54 headers?

They were massaged a little.

[08SlowE82]

Here you go

[rjahl]

Originally Posted by hoveringuy

For what it's worth, this is my N52 with S54 headers, N54 intake and a throttle body, otherwise no other changes.
I tried running without the throttle body but couldn't get it to run smooth enough to satisfy my OCD, particularly down low in the cruise regimes, although it ripped up top and at WOT. The engine model in the DME just wasn't close enough. With LOTS dyno time that could have been resolved but there's no compromise made with the MAF.
The dyno plots show MAFless vs MAF, and the MAF filled-in the bottom end nicely and just runs smoother all around.
It actually makes a little more power but something about the rate of acceleration on the inertia dyno related to the predictive rev limiter starts pulling power right after 7000.

Nice job, I think this is the highest RWHP I've seen with an NA version of the N52. Maybe worth a single post and a sticky.

[08SlowE82]

I would suggest you really pay attention to where your Air fuel ratio is at under a load.

[hoveringuy]

Originally Posted by rjahl

Nice job, I think this is the highest RWHP I've seen with an NA version of the N52.

Thanks, that's what Hassmaschine said, too. (he did the DME integration, which is considerable on an e30...) It's literally a bone-stock long block with an N54 intake and kick-ass headers. Single 2.75" exhaust and a Burns merge.

The one hint I can add is that the PS regulating spindle is interchangeable between the Luk pumps used in different model cars. Stock on this motor was 130bar, which was WAY overboosted and cooked my PS fluid on the track. I dropped-in the regulator from a Porsche Cayman (same pump, but only 100bar. Mid engine, FTW..) and it added some nice weight and feel to the steering and reduced PS temps considerably.

[Dru128m]

Well guys the open trumpets are dead. Bob has tried to disable this and that, tweak here and there, and it just won't fuel right. To many safeties built into the stock dme is the culprit, I'm being told. You can do it, it had good moments, but was never really happy about it. It's been like 10 months now, I really want my car back in order. For now I'm bolting on a n54 manifold to get things back in order. It will have MAF, MAP sensors, a throttle body. Modern engines rely on their sensors to function properly, who would've thought. Sorry to get anybody excited, it's quite the let down. Mechanically it works just fine, but you'd need a aftermarket ecu that can run the valvetronic. Maybe that exists, but it's not in this budget. I still have an idea that gives me a glimmer of hope for open trumpets on this motor in the future, but that idea is going in the freezer for now.

[Biginboca]

Originally Posted by Dru128m

Well guys the open trumpets are dead. Bob has tried to disable this and that, tweak here and there, and it just won't fuel right. To many safeties built into the stock dme is the culprit, I'm being told. You can do it, it had good moments, but was never really happy about it. It's been like 10 months now, I really want my car back in order. For now I'm bolting on a n54 manifold to get things back in order. It will have MAF, MAP sensors, a throttle body. Modern engines rely on their sensors to function properly, who would've thought. Sorry to get anybody excited, it's quite the let down. Mechanically it works just fine, but you'd need a aftermarket ecu that can run the valvetronic. Maybe that exists, but it's not in this budget. I still have an idea that gives me a glimmer of hope for open trumpets on this motor in the future, but that idea is going in the freezer for now.

I wouldn’t call this a bummer, your car is a daily then this is definitely the way to go. Bob did my tuning also and when I wanted to go MAF’less about 3 years ago he talked me out of it. Since then I have 50k miles on N54 manifold, n54 TB, all the fixin’s (MILV’s, Headers, etc) and Bob’s tune. Car is smooth as silk at all rpms, starts and idles like stock, and zero hiccups. I would not hesitate to drive it cross country tomorrow right over the Rocky Mountains

I have not had one hitch, misfire, issue, or concern. That’s daily driving hitting 7500rpms daily… plus quite a few track days… for over 3 years now!

Dependability and Driveability trumps the extra 5hp or so if you ask me. Dependability is why we all chose the N52 after all, right?

[Dru128m]

Dependability is right. I have flogged my n52 for years now and it's never let me down. It was honestly breaking my heart having it in less than ideal running condition. I didn't run a single auto x all summer cuz the tune was wonky. I did enjoy the motorcycles all summer, but I wasn't my 1er back in action.

[dragonsi]

Originally Posted by hoveringuy

They were massaged a little.

Are these oem euro s54 headers?

[hoveringuy]

Originally Posted by dragonsi

Are these oem euro s54 headers?

These were US spec S54 headers.

[Dru128m]

Alright N54 manifold is plumbed in. All sensors reinstalled and dme flashed back to stock. Started right up and test drove around the block just fine. It's already running better than with the trumpets, can't wait to see what Bob can do with it. The upside down picture gremlin strikes again, sorry.

[desertman123]

Even if it's not a success it's valuable R&D