[FrankiE90]

updated //

[Slops]

STICKEY this thing... I always have to search for this thread!

[shockin330i]

Sound clip for AR downpipe
Cold start

[FrankiE90]

hey guys i wanna talk bout exhaust and gains for the N55.

As some of you may know i've been prep'n to dyno
Injen's intake and in doing so I found some interesting finds in my
exhaust + oem intake from my recent pulls.

To fill you in, this is the process I've taken in the past week or so.
-received new injen intake - test driven no dyno.
-then removed intake, took e90 to dealer for 15k service (scheduled service)
-E90 was reprogrammed according to mandatory update.
-drove a few days with stock intake, for adaption to settle with bimmer
-Dyno'd with vanguard exhaust and stock intake.
-removed stock intake, installed injen intake -
-been driving around a few days with injen intake, letting the adaption feature settle before dyno.

I got the numbers for the dyno with the exhaust + OEM intake.
and look'n at these numbers compared to my baseline numbers
it show some loss in power.




I lost a few whp, torque number seems to be fine but pass 5800k
you'll see the drop up top. There were no gains.

Looking at these numbers lead me to think -
that the oem exhaust really does not have a restriction.
Unlike the N54 or the N55 xi where you'll have cats the only
restriction the n55 does have are the double cats on the DP.

does the N55 xi have 1 or 2 cats on the DP?

Honestly the exhaust adds great sound but i see no gains.
anyone else do a dyno with their aftermarket exhaust?
if the findings are similar, I would make the conclusion
that gett'n the Catless DP before an exhaust would make more
sense. I have DP's and the procede next up to bat for my N55.
I like to see if any gains would come out of DP's and a after market
exhaust for our N55.

let's discuss.

[Slops]

Seriously, please stickey this thread

[Slops]

Wow Frankie, this makes my choice to just go with only the Vishnu downpipe a great one. If there's non real gain after the downpipes, then why bother unless you like the sound. I'm in love with the vishnu sound and stock exhaust though so that would be great for me at least. I'm guessing that i'll skip the full exhaust "upgrade" and stick to the dp, intake, fmic, and last but not least Procede.

- Side note... this was the same Dyno right? Just a little difference in temp and humidity but i can't imagine it would affect the hp that much.

[IancoleTX]

That can't be right. A ~50whp loss at 6500 rpm from installing an exhaust?

That makes no sense.

Also, did you just bolt up an n54 exhaust, or..? Just wanted to confirm there was direct fitment.

[Slops]

yeah, what is going on at that top end?

[FrankiE90]

Originally Posted by Sloppy

Wow Frankie, this makes my choice to just go with only the Vishnu downpipe a great one. If there's non real gain after the downpipes, then why bother unless you like the sound. I'm in love with the vishnu sound and stock exhaust though so that would be great for me at least. I'm guessing that i'll skip the full exhaust "upgrade" and stick to the dp, intake, fmic, and last but not least Procede.

- Side note... this was the same Dyno right? Just a little difference in temp and humidity but i can't imagine it would affect the hp that much.

it seems to be like that Sloppy.
my first priority for performance mods are gains.

Let's get other guys to chime in and we'll
have a talk bout route in power mods for the n55.

side note - yes same dyno place MD Automotive
also was on 19's, base dyno was on 18's. all 91oct gas.

Originally Posted by IancoleTX

That can't be right. A ~50whp loss at 6500 rpm from installing an exhaust?

That makes no sense.

Also, did you just bolt up an n54 exhaust, or..? Just wanted to confirm there was direct fitment.

not 50whp loss. look at dyno again. increaments in quarters - it's more like 12-15whp loss up top.

Originally Posted by Sloppy

yeah, what is going on at that top end?

looks like a drop in power.
i was try'n to figure out if it was the updated software from BMW/dealership.

[shockin330i]

Originally Posted by FrankiE90

it seems to be like that Sloppy.
my first priority for performance mods are gains.

Let's get other guys to chime in and we'll
have a talk bout route in power mods for the n55.

side note - yes same dyno place MD Automotive
also was on 19's, base dyno was on 18's. all 91oct gas.





not 50whp loss. look at dyno again. increaments in quarters - it's more like 12-15whp loss up top.




looks like a drop in power.
i was try'n to figure out if it was the updated software from BMW/dealership.

You should have dynos wth the stockers.

[IancoleTX]

Originally Posted by FrankiE90

not 50whp loss. look at dyno again. increaments in quarters - it's more like 12-15whp loss up top..

Not at all trying to argue bro but the Y-axis goes from 0-400 hp. At 6500rpm, you are dropping from ~292whp to ~242whp. Am I missing something?

[RyanMv4]

Originally Posted by shockin330i

You should have dynos wth the stockers.

Yeah you'd be suprised the HP drop that comes from a size bigger wheels

[FrankiE90]

Originally Posted by IancoleTX

Not at all trying to argue bro but the Y-axis goes from 0-400 hp. At 6500rpm, you are dropping from ~292whp to ~242whp. Am I missing something?

Ian i guess ur right.
just check on the readings on the dynojet software.
6.51RPM - 299.38whp / 250.84whp
big drop.

Originally Posted by shockin330i

You should have dynos wth the stockers.

Originally Posted by RyanMv4

Yeah you'd be suprised the HP drop that comes from a size bigger wheels

damn.
- should've dyno'd with stockers.
next run i'll keep the 19's on to be consistent for the intake.
-
still want to find out what the gains/loss for the exhaust are though.
now i'm wondering how much drop in power between 18's and 19's.
does wheel weight factor in too?

[IancoleTX]

Originally Posted by RyanMv4

Yeah you'd be suprised the HP drop that comes from a size bigger wheels

lol dude what

[shockin330i]

Originally Posted by FrankiE90

Ian i guess ur right.
just check on the readings on the dynojet software.
6.51RPM - 299.38whp / 250.84whp
big drop.





damn.
- should've dyno'd with stockers.
next run i'll keep the 19's on to be consistent for the intake.
-
still want to find out what the gains/loss for the exhaust are though.
now i'm wondering how much drop in power between 18's and 19's.
does wheel weight factor in too?

Yes

[IancoleTX]

Originally Posted by shockin330i

Yes

Very interesting.

[FrankiE90]

good video ernie.

[shockin330i]

Originally Posted by FrankiE90

good video ernie.

I didn't make it, but I'll take credit for finding it for you

[RyanMv4]

Originally Posted by IancoleTX

lol dude what

Yeah it does trust me Ive had a 12 hp loss in the evo when I used to have it by running heavy 19's vs my 18 inch wheels... Gotta use more power to turn those bigger wheels

[Slops]

That vid is insane... Good post.

[IancoleTX]

Originally Posted by RyanMv4

Yeah it does trust me Ive had a 12 hp loss in the evo when I used to have it by running heavy 19's vs my 18 inch wheels... Gotta use more power to turn those bigger wheels

That's crazy, 12 hp loss on how many whp?

[RyanMv4]

Originally Posted by IancoleTX

That's crazy, 12 hp loss on how many whp?

I cant remember exactly I wouldnt have believed it if i didnt see it on my own car haha