gaspam

installed my speedriven catlessdownpipes (non- turbo back) finally and not too bad but definitely a pita when doing it on floor ramps, floor jacks and jackstands... but i dont have a garage with lift (yet) so had to do it that way... took about all day as getting it all up in the air and secured and getting all the under carriage mouldings off took some time and lots of bolts to undo... hardest part was getting the o2 sensor out of clips (as they are almost on top of tranny) and unplugged (needed a extra long set of angled needle nose pliers for that.... then separating the other end of pipes from resonator area required using pry bar (against rear diff area) to push muffler/resonator section back just enough for the old pipes to slide out...

install is reverse and the o2 wires are stretched to max on passanger side and upper o2 on driver side is very close to steering shaft rubber boot... gonna recheck it in a few weeks to see if any noticeable rubbing on the o2s is occuring, but so far no vibration or exhaust leaks...

sounds factory at any speed other than WOT, which is what i expected... little more turbo whistle sound noticeable, but only if i have music off ( i like the jet sound though)

check engine light came on within 30 min of first drive but expected... taking it to renntech next friday for re-tune and dyno tune.


here is a vid of just normal driving and then flooring it so you can get idea of in cabin sound... not loud at all, as expected since not really any sound deadening components are removed.









towards the middle of the car there is like some under carraige paneling that feels like its carpeted and has a bunch of plastic rivits below... i used needle nose pliers to remove them without breaking them





the bolts to remove old pipes and install the new ones need a extension bar and the one on the drive side closes to tranny needs swivel attachment too as its pretty tight quarters






3 hangers to undo as well ...

one of these...



and 2 of these (one on each side)




all the bolts are normal hex except the ones that clamp the resonators but i was able to get them off with normal 12 point socket vs the actual torx




other than that it was pretty smooth sailing .... expect some scrapped hands and cuts especially when getting the o2 wires out of the metal clips as they are sharp as doo doo!

gaspam

here is a quick sound clip from out side.... definitely not too loud

chiromikey

Good write up!

It's hard to come to any conclusions from videos but I wonder if the bridge pipes on the turboback set up contribute to any extra sound. I'd say my car was louder than yours but there's probably not much to debate since the cars aren't side by side to compare.

kponti

I agree my car sounds louder in cabin than yours gaspam. Maybe cos of the bridge.

gaspam

thanks!

did you do the same pipes Kponti did from upd(pretty much same as EC and cks ones i believe)? if so you should do a dynojet dyno as i know he is doing dyno dynamics (i think) and then maybe we can all finally get a good ballpark what the turbo pipes are worth in gains over dp's everyone else is selling (mid pipes) as the info is pretty much non-existant and would be great to know... i still may do bridge pipe replacement , but just got to make sure the gains (and gains under the curve) justify the cost

I will be doing dynojet soon (thats what renntech has) so would be nice to see a dynojet turbo pipe run as well ( i think it will be sae corrected)

chiromikey

I actually did do pre and post dynos but my post dyno numbers and curves were suspect and it wasn't until after that I found my intake tubes unraveled and sucked into the air boxes...not to mention they didn't turn the ac off and had cel's lighting the dash up like Christmas because they didn't put the car into dyno mode. I haven't had time to go back nor the inclination to pay them for another dyno run. :-/

Fairbird

sounds good in my taste . I went different rout though

gaspam

^ nice! W3 kit too right? when's the bullet proof tranny supposed to be ready for you?

gaspam

that sucks... where the pre-numbers suspect or just the post numbers? If the pre numbers look legit, i would find another shop and get some post numbers so we can start getting some compiling some data and get good ideas of what turbo back vs mid pipes diff really is

i think we are the first generation of m157 owners that really car about this kinda research and progress kinda like back in 2003-2006 no one cared much about going past shorty headers and a 168m pulley on the E55's and then when they got cheaper a new wave of guys came in that wanted more and put in the time and research to push that platform into low 10's knocking on 9's now

Fairbird

Yes the w3 kit is there , 3-4 weeks of wait .

kponti

Yes I agree. The main reason I didn't just lease a new one (would have been similar in cost since I don't drive much anymore). But I tend to fiddle with my cars and end up ***** deep in before I know it

PeterUbers

Very cool man, we'll done, definitely above my technical pay grade!! Do you feel butt dyno before and after gains

I'm at Disney with the family and having e63 withdrawal

chiromikey

No, pre numbers were where they should have been...but I also know the intake tubes only had a few holes and were still mostly intact at that time. I'd like to go back to the same dyno so my baseline numbers aren't useless but I'm not hip to the fact that they want to charge me full price to do it again.

gaspam

at first it actually felt a little slower as i am sure the ecu was thinking it was running lean so started dumping fuel, but ecu seems to be learning a little as definitely feeling faster now, but not mind-blowing but the ecu on our cars can only learn so much, Im sure it will feel quite a bit different next friday when i am retuned for downpipes at RT

chiromikey

I just can't figure out these turbo cars. By freeing up the exhaust, turbo cars should be faster. Since you already had a tune I wouldn't think it would feel slower.

The reason I'm pondering this is that I just removed my resonator and I swear it feels slower...like losing back pressure on the 55k or a n/a car. I've put plenty of miles on it so its not an ECU learning curve. So confused...

kponti

Backpressure reduction will not lose power/torque in either s supercharged or turbocharged car. Hell it will not lose power on a NA car either (unless we are talking headers).
Perception however is not always accurate (ie butt dyno). I still remember when the ZR1 (1990-1995) was perceived as gutless compared to the L98 when in reality the LT5 held torque over a much broader rpm range than the L98

Think about it for a sec, MB cut boost and pumped it back on some shifts to simulate faster shifts on the MCT. Which means smoother shifting DSG is faster but doesnt feel as fast. Butt dyno losing on that one

Pumpkinate

What is the theory behind the claim of reducing backpressure not being good with N/A cars? I see the claim a lot but can't see how it could be.

chiromikey

We talk about it as if we're losing power but as long as there's a proper tune I think what's really going on is that the power band is shifting to higher rpms and we're missing the feel of the low end tq.

kponti

I never ran my car with downpipe without a tune so I don't know what gaspam experienced, but usually a tune will make up for any lean spots or rich spots that will show up on a Dyno as lost power or Torque.
Removing the resonator does not really reduce back pressure. If you look inside the stock resonator you see that outside of the small connector that links the two Banks, everything else is the same as two separate pipes.
I had a removable resonator built like the stock amg ones on previous cars (stainless steel packed tight around perforated pipes, MagnaFlow has plenty of these for sale). There was no change in power for even curves with or without. However definite change in sound.

gaspam

the "back pressure needed" saying is pretty much a myth..Back Pressure doesn't help anything. The saying that bp helps torque is because a smaller exhaust tube usually has more back pressure, but actually the smaller tube lets velocity stay high with less throughput. If you can get a larger bore yet keep velocity up, then you don't take a HP hit at high flow, and you keep your velocity at low rpms. That's part of why a long tube really works, the large tube doesn't take high rpm hits, but at low rpm, the long tube tuning waves keep velocity up, so tq doesn't take a hit.

here is a good explaination on this myth

http://www.mustangevolution.com/forum/f312/t296628/

TX E55

Thanks for posting, my downpipes go in next week. But I have to say, this is the best quote I have seen in a long time...

"But I tend to fiddle with my cars and end up ***** deep in before I know it"

Classic!

kponti

Lol

Zod

Thanks for the feedback guys, really looking forward to the comparison as it helps us al learn.

must....resist...moding bug...itch... ahhhhhh too STRONG (am on the right, incase you were wondering)