[335boston]

Hello everyone,

Just wanted to make a little post to see if anyone had a loss of power with their n54 FBO and had any solutions , I read on a couple posts that the n54 is known for this but only solution I found was to upgrade turbos , wondering if there was anything else you can do to get it more powerful up top? I'll attach my dyno log below ! I was also wondering If I switched over to Dinan mufflers would I gain any more hp?

Ps. This log was on a bad fuel bump (went dead a week after) and a slipping clutch (started slipping after dyno log) so I think that may have been a slight factor.

Engine mods are :
Vrsf 7in intercooler
Cobb charge pipe with stock dv
Bms intakes
Jb4 with pump BEF
Catless downpipes
Catless mid pipes (stock mufflers)

[relative4]

That's not a log, it's a dyno chart. Post a log. In the N54 forum.

[NoGuru]

This is how all stock N54 turbos Dyno's look. The problem is the physical limitation of the turbos.
They are designed to give low end torque but fall off around 5500 RPM.

[335boston]

Originally Posted by relative4

That's not a log, it's a dyno chart. Post a log. In the N54 forum.

Sorry ahha I meant log as in dyno log

[335boston]

Originally Posted by NoGuru

This is how all stock N54 turbos Dyno's look. The problem is the physical limitation of the turbos.
They are designed to give low end torque but fall off around 5500 RPM.

Hey thank you , just wanted to make sure , really sucks how they have that power down low and just die up top I was hoping for some mods to help it other than replacing turbos .

[neilvan]

turbo inlets can help a bit with top end but itll never be a high rpm car unless you go bigger turbos

[type-dRew]

normal, shift at 6k

[NoGuru]

Originally Posted by type-dRew

normal, shift at 6k

Yep, like dRew said, shift about 6K to stay in the power band.

[Torgus]

N54 stock twins die at 5.5-6k and the tq and HP NOSEDIVE.

It does not matter what you do, nothing can change that. You need twins with larger wheels or a single turbo to fix.

That being said your dyno reads a bit low from FBO w/ tune on 93 iirc.

[NoGuru]

Originally Posted by Torgus

N54 stock twins die at 5.5-6k and the tq and HP NOSEDIVE.

It does not matter what you do, nothing can change that. You need twins with larger wheels or a single turbo to fix.

That being said your dyno reads a bit low from FBO w/ tune on 93 iirc.

I thought it was a little low as well but maybe that is the COBB?
Or just maintenance.

[335boston]

Hey thanks everyone for replying ! I guess I'll just have to stick with the loss in too in because I don't think I'll be able to get new twin in anytime soon . I'm happy someone brought up the power , the was my next question . This dyno was on a dying fuel pump and a stock clutch that had 100k on it . Since then I have dialed in the tune better with the help of BMS have a new Bosch fuel pump in and a 335is clutch installed . What power you guys thinking I should be at? Should I re dyno with all the new equipment / fixes? I thought nearly 400 wheel tq was pretty good for it but I also thought I'd get more hp to wheels. Lmk what your thoughts are thank you !


Car also now has almost 105k on it .

[335boston]

Also forgot to add I'm also using the correct ngk plugs gapped to spec from bms along with elder coils (threw these on after tuning about a year ago)

[Torgus]

I would post a log WOT in 3rd starting at 2k to 7200rpm and shift into 4th for a bit. That will tell a lot and make sure everything is working correctly before dynoying again. A single gear pull with no gear shift is not as useful. A log will tell a lot more than a dyno and is free.

As we are both from Boston, where did you dyno?

[335boston]

Originally Posted by Torgus

I would post a log WOT in 3rd starting at 2k to 7200rpm and shift into 4th for a bit. That will tell a lot and make sure everything is working correctly before dynoying again. A single gear pull with no gear shift is not as useful. A log will tell a lot more than a dyno and is free.

As we are both from Boston, where did you dyno?

I've got a couple logs on my JB4 are those okay to post / how can I send that to this post ? I did my dyno at prime speed in rowley . It's the closest place around which is still 40 mins from Boston lol

[Torgus]

You can post them here. Or on the JB4 forum.

[335boston]

Originally Posted by Torgus

You can post them here. Or on the JB4 forum.

How do I attach to this post ? As a csv file?

[Torgus]

I don't have a JB4 but I usually see people post a screen shot of the log that has been already graphed.

A .csv file is fine as well, but harder to read unless you graph it.

https://datazap.me/ is the easiest way and what is preferred on the forums as you can upload your csv and we can all see the data and what not. Datazap is the best way in my opinion.

[335boston]

https://datazap.me/u/brabbit1214/jb4...0&data=1-4

Just tried the app for the first time let me know if I managed to do it correctly sorry in advances because chances are I did lol! Lmk what you guys think

[335boston]

Also wanted to ask everyone's opinion on an exhaust , is it worth ? How free flowing are the Dinan mufflers compared to stock? To me all the Exhausts sound the same so I haven't bought one . Lmk what you guys think!

[Emilime75]

You're not going to gain much at all by replacing the mufflers. You've already removed the most restrictive parts of the exhaust, which were the cats.

The only further benefit would be some weight loss, and more noise, if you're into that sort of thing.

[335boston]

Originally Posted by Emilime75

You're not going to gain much at all by replacing the mufflers. You've already removed the most restrictive parts of the exhaust, which were the cats.

The only further benefit would be some weight loss, and more noise, if you're into that sort of thing.

Ah I see thank you , so it seems the oem mufflers arnt too restrictive at all?

[jwalker87]

I don't have post-install dyno numbers, but I installed the MMP silicone inlets and outlets (LINK and LINK) and am pretty happy with them. I can no longer run JB4 Map 5 because the stock clutch starts slipping, so that's a good sign power-wise, lol! I keep it at Map 2 and everything is happy; eventually I'll install a 335is clutch and go from there.