[Biginboca]

Originally Posted by Wolf 335

Subbed.

have you done a smoke test on your system for leaks?

I didn’t do a smoke test... but I did the backyard standard “carb cleaner spray” test

[Taskmaster]

Originally Posted by Biginboca

I’m on stock airbox now but with the AFE was using the foam ring they supply to go around the MAF sensor. Is that the gasket you mean?

The actual intake tract I had to make custom to line up with the n54 manifold. There are definitely no leaks in the intake tract I made from the MAF sensor to the throttle body.

Yeah, the foam ring for the MAF. I would call up AFE and see if you can get a new one.

[hassmaschine]

Originally Posted by Biginboca

hassmaschine any chance you can expound on why you prefer a mafless tune?

Forgive my lack of knowledge, it seems to me like when you are getting into MILV’s, headers, and now potentially exhaust cams the MAF tune would be easier to work with?

I'll go pull my adaptations later today, but no - it's not any easier or different to work with. If anything, the no-MAF tunes are easier because you don't have to deal with issues related to the MAF housing, airbox, MAF failures, connector failures, vacuum leaks, and low-speed resolution.

The no-MAF tune will adapt just like the MAF will. Full load fuel is all target based anyway. It's all based on the primary O2 sensors.

Also I got the no-MAF tune working with headers now (no more wacky fuel trims!). For the 328i I'm still working on resolving issues with cruise control, which is not present on the model I based the tune from.

For preferences - try driving your MAF based car at a low speed in 1st gear. Say, 1000-800rpm. I'll bet it's impossible to do it even under 1200rpm.

[Biginboca]

Originally Posted by hassmaschine

I'll go pull my adaptations later today, but no - it's not any easier or different to work with. If anything, the no-MAF tunes are easier because you don't have to deal with issues related to the MAF housing, airbox, MAF failures, connector failures, vacuum leaks, and low-speed resolution.

The no-MAF tune will adapt just like the MAF will. Full load fuel is all target based anyway. It's all based on the primary O2 sensors.

Also I got the no-MAF tune working with headers now (no more wacky fuel trims!). For the 328i I'm still working on resolving issues with cruise control, which is not present on the model I based the tune from.

For preferences - try driving your MAF based car at a low speed in 1st gear. Say, 1000-800rpm. I'll bet it's impossible to do it even under 1200rpm.

I’m not sure what you mean, why wouldn’t that work? I’m guessing you suspect there will be some kind of feedback loop with the MAF tune?

I cruise at idle all the time in my neighborhood. I have an automatic guard gate so I slowly idle up to it in first gear while it opens never an issue. I just came home and made this video entering my gate and then passing over the speed bumps in first gear the whole time no clutch. I don’t use the brake or clutch in my neighborhood just first gear and throttle from the gate to my house and I can drive the car smoothly at idle (~600rpms) and up in first gear indefinitly

[Biginboca]

Originally Posted by Taskmaster

Yeah, the foam ring for the MAF. I would call up AFE and see if you can get a new one.

I can see how that foam ring might cause a problem, but it looked like on my intake that foam around the MAF seemed to be sealing pretty well when I swapped the intakes 2 days ago.

Now I’ll say this, if that foam is the issue... I wouldn’t want another one. AFE can bugger off I’d rather make something else to seal that actually works lol

[hassmaschine]

Originally Posted by Biginboca

I’m not sure what you mean, why wouldn’t that work? I’m guessing you suspect there will be some kind of feedback loop with the MAF tune?

I cruise at idle all the time in my neighborhood. I have an automatic guard gate so I slowly idle up to it in first gear while it opens never an issue. I just came home and made this video entering my gate and then passing over the speed bumps in first gear the whole time no clutch. I don’t use the brake or clutch in my neighborhood just first gear and throttle from the gate to my house and I can drive the car smoothly at idle (~600rpms) and up in first gear indefinitly

It works, it's just way smoother without the MAF. At low engine speeds, there's not enough velocity over the sensor for it to read accurately. I never noticed until I did the delete, then drove our old E91 which still had the MAF.

[Biginboca]

Originally Posted by hassmaschine

It works, it's just way smoother without the MAF. At low engine speeds, there's not enough velocity over the sensor for it to read accurately. I never noticed until I did the delete, then drove our old E91 which still had the MAF.

Why do the euro cars not have the MAF? I’m guessing the MAF contributes to emissions compliance and fuel economy more than it helps performance characteristics...

[hassmaschine]

Because that's how the N52 was designed. And yes, I think your guess is correct.

[rjahl]

Originally Posted by hassmaschine

Because that's how the N52 was designed. And yes, I think your guess is correct.

Do you think the DME manages fuel trim by cylinder or by bank? In other words can the DME and O2 sensors monitor individual cylinder mixtures.

[hassmaschine]

the fuel trims are by bank. You can manually trim individual cylinders but you'd need more data to do that effectively.

[desertman123]

Just chiming in I've been running Euro IAT, MILVS, headers & 3IM + no MAF tune for months no issues

[Biginboca]

Originally Posted by desertman123

Just chiming in I've been running Euro IAT, MILVS, headers & 3IM + no MAF tune for months no issues

Are you running a BPC tune? And did you do a dyno of that set up?

[mrnuke]

Originally Posted by Biginboca

Are you running a BPC tune? And did you do a dyno of that set up?

pretty sure hassmachine set him up with a tune, and I'd be curious to see dyno numbers as well!

[desertman123]

Originally Posted by Biginboca

Are you running a BPC tune? And did you do a dyno of that set up?

I'm running Hass' tune, and no, no dyno. I want to dyno it but i never got a baseline.

[Biginboca]

It’s been 4 days and I haven’t gotten any codes with the only change being replacing the AFE intake with the stock airbox, and we have had a cold front come through so the conditions are the same as last week when I had codes 3 times in a few days.

I think I’m going to just add the ram intake to the stock airbox and run it permanently...

[Wolf 335]

Originally Posted by Biginboca

It’s been 4 days and I haven’t gotten any codes with the only change being replacing the AFE intake with the stock airbox, and we have had a cold front come through so the conditions are the same as last week when I had codes 3 times in a few days.

I think I’m going to just add the ram intake to the stock airbox and run it permanently...

Have you seen this thread.

[desertman123]

I do gotta say low speed partial throttle is extremely smooth and responsive. With the MAF its a bit more jerky

[Biginboca]

Originally Posted by Wolf 335

Have you seen this thread.

I looked at that thread, thanks. That was a strange anomaly where it ended up being bad injectors over time fried the ecu. I don’t see signs of my issue being injectors based on what I was able to see watching my fuel trims.

Speaking of which, I’m not able to watch my trims any more because my Carly ap stopped working and their tech support hasn’t answered multiple emails over the last 2 days. But as of the last time I watched my trims 3 days ago they looked really good, and all within norms.

And I still haven’t had any lean codes and car is running well with stock airbox.

[hassmaschine]

that is a 335i so it's pretty much irrelevant anyway - the fuel system is completely different. We don't have issues with bad injectors typically (port injection FTW).

[Biginboca]

I finally got around to measuring the MAF area of the stock airbox and the AFE intake around the MAF area.

Stock ID at the MAF is 3.0”
AFE ID at the MAF ~ 3.125”

No wonder my fuel trims have pretty much cut in half since I swapped back to stock airbox.

From research I have done this week on airflow it seems that a 3” pipe approx 1 foot in length at 1atm will flow over 500cfm with less than a 5% pressure drop.

Our motor at 7500rpms would need ~400cfm and 450cfm would allow it to hit a theoretical 300bhp.

So a stock 3” maf housing diameter would seem to be sufficient depending on how much the actual maf sensor obstructs the airflow. (From what I’ve read an unobstructed 3” diameter pipe 12” long should be sufficient for up to like 330 N/A HP)

Also since K&N specs their stock drop in filter for our airbox at 518cfm using a stock airbox with a k&n drop in should provide all the airflow our motor needs even with every available mod we can do in place.

My conclusion is on my car running a MAF I should stick with the stock airbox and MAF section and then do flow mods like the Dinan style RAM, a drop in filter, charcoal delete, and REV silicone.

If you have Alpha N tuning and an increased redline then screw all that and run the AFE intake... or go even bigger and make a smooth and unobstructed 3.25-3.5” intake tract.

One question I have is this...

Did AFE open the MAF area 1/8” larger than stock figuring the increased airflow would cause a lean condition but it’s slight enough that the motor could still address with more fuel and it would be below the threshold to throw codes.

And I wonder if on my motor I’m flowing so much more air with the mods I’ve done that it’s above that “no lean code threshold”. Like some of the mods I’ve done are outside AFE’s calculations. (Big bore TB, n54 intake, MILVs, Headers, No Cats, etc)