Ever since I got my E55 a few weeks ago, I knew something was not right with it. The car lacked power and would hesitate/surge...very annoying. I removed the MAF sensor and cleaned it...didn't make any difference. So this morning I decided to just go down to the Smythe dealer and bend over. I got a new genuine MAF sensor for $435 out the door...what a bargain
I also took the car down to my local exhaust shop and had them remove that POS 30 lb. resonator and weld in 2.5" straight pipes. Only cost me $100 and it sounds absolutely perfect! It's noticeably louder, but not the drone I was afraid of. I couldn't notice any performance difference with the resonator delete but the sound alone was worth it - it's exactly what I wanted.
Now, I wasn't expecting much with the new MAF sensor (I'm a skeptic by nature), but let me tell you, it made a HUGE difference. The hesitation is gone and throttle response is much snappier. WOT performance is like night and day. The acceleration is brutal now. If I roll away from a stop and then punch it, it kicks down into first and the rear tires go up in smoke. It'll haze the rear tires for what seems like several hundred ft I have no doubt this is a low 13-second car now if launched properly with minimal wheel spin. I'm going to take it to Infineon Raceway for Wednesday night drags to get a baseline. So far, the only mods I've done are K&N air filters, ported throttle body elbow, and resonator delete. I've also intalled the new MAF and removed the spare tire, tools, etc. It runs much better than when I picked it up a few weeks ago and I haven't even tuned up the motor or changed any fluids yet.
I also threw the big German luxo-musclecar into some high-speed corners and expected it to get sideways with a bunch of tire squeal, but I was VERY surprised. The car is super stable and handles a lot better than I expected. I'm liking the E55 more every day OK, here are some pics of my dirty car:
humm, interesting, I will have to check my MAF, I know these car have a known problem with the MAF. Looking forward to seeing your car in person next week to check out your mod.
It only has 52K original miles and the MAF sensor was definitely shot. They are known to go bad on our cars...the parts guy at the dealership said they had 24 in stock, if that's any indication. I was going to get one off eBay for half the price, but I wanted it fixed today so I paid the stealership prices.
interesting pictures. but what does it look like after you removed all those "gills" and etc? do you have a picture of the unit completely debaffled? i wonder what purpose those serve b/c it does seem that the flow would be much better with just a huge open pipe instead of those gills in place.
Also on the resonator, how does it sound now? is it annoying? ANY droning at all? Does it actually sound like a V8. Looks great the only downside is you did not use mandrel bent piping which may restrict airflow slightly compared to mandrel bent pipes but im sure it probably still flows better than stock resonator. Anyways thanks for the pics mrwheelr!! keep up the good work
Sorry to hear about your MAF failed, it was a low miles too. Anyway, I was in the shop this morning having a tranny fluid service and since the car was on the lift while checking the underbody for anything we notice our big and heavy (I was surprise about the weight you said 30 lb)resonator and me & my tech was discussing about the resonator to delete or not to delete, but concerned also on how it's going to sound since that basically the major benefit your getting. do you have any wave file you can share about your new exhaust set-up? I was thinking of doing that before but can't find a decent muffler shop that know how to weld and bent pipes properly here in my area.
Cleaning MAF sensors doesn't seem to work. I used the CRC MAF sensor cleaner with Q-Tips and went over it half a dozen times and the same symptoms were still present. Replacing the sensor definitely restored my E55's power
I know the tubing isn't mandrel, but I had them use 2.5" instead of our stock 2.25" so the pipe is actually slightly larger in diameter. I can tell you it certainly didn't hurt performance plus I shaved off at least 20 lbs...not sure exactly how heavy that resonator is, but it's not light.
The sound is awesome. Nice mellow tone until I punch it and then it growls like a high-performance V8 should. It's doesn't drone...keep in mind there are still four cats and two mufflers in the system. If anything, I might want it a little louder, but only at WOT.
The car has basically brand new Pilot Sport tires on it and the insides of the rears are already worn down pretty deep. I can tell this car is going to make short work of those 275's.
Cleaning MAF sensors doesn't seem to work. I used the CRC MAF sensor cleaner with Q-Tips and went over it half a dozen times and the same symptoms were still present. Replacing the sensor definitely restored my E55's power
I know the tubing isn't mandrel, but I had them use 2.5" instead of our stock 2.25" so the pipe is actually slightly larger in diameter. I can tell you it certainly didn't hurt performance plus I shaved off at least 20 lbs...not sure exactly how heavy that resonator is, but it's not light.
The sound is awesome. Nice mellow tone until I punch it and then it growls like a high-performance V8 should. It's doesn't drone...keep in mind there are still four cats and two mufflers in the system. If anything, I might want it a little louder, but only at WOT.
The car has basically brand new Pilot Sport tires on it and the insides of the rears are already worn down pretty deep. I can tell this car is going to make short work of those 275's.
cleaning MAF's does work but not with the CRC method, i tried that too it made things worse on my old MAF. but alcohol method is fantastic, car feels brand new again. however u are not supposed to use Q-tips, it will damage the sensor (they are very sensitive).
I really want to do the resonator pipe as well. so 2.5" is not too big diameter for the piping?
I have no doubt this is a low 13-second car now if launched properly with minimal wheel spin. I'm going to take it to Infineon Raceway for Wednesday night drags to get a baseline. So far, the only mods I've done are K&N air filters, ported throttle body elbow, and resonator delete. I've also intalled the new MAF and removed the spare tire, tools, etc. It runs much better than when I picked it up a few weeks ago and I haven't even tuned up the motor or changed any fluids yet. 
OK, here are some pics of my dirty car:
Linear Mode
