Are upgraded outlets worth it with upgraded turbos

[SLOWESTN54]

Been reading up about upgraded outlets, and i can't find much besides stock turbo stuff. Wondering If anyone has some experience with upgraded spooly bois and outlets.

Edit: Aiming for 600+ and over 23psi

 

[SlowE93]

Been reading up about upgraded outlets, and i can't find much besides stock turbo stuff. Wondering If anyone has some experience with upgraded spooly bois and outlets.

Edit: Aiming for 600+ and over 23psi

I would think the turbo manufacturer would know best since they know what the capabilities are of said turbos.
Perhaps contact Chinese Turbo Systems and see what they say ?

 

[SLOWESTN54]

I would think the turbo manufacturer would know best since they know what the capabilities are of said turbos.
Perhaps contact Chinese Turbo Systems and see what they say ?

@fmorelli Change his name to The Grinch

Thank you in advanced!

 

[Torgus]

I was always a bit skeptical of the gains from outlets. Especially when MMP's name was tied to them at the beginning: https://www.spoolstreet.com/threads/let-talk-outlets.2343/

Outlets are cheap, I say why not while you are in there. They aren't going to hurt anything and they can only help, as long as you don't burn a hole in them. I would suggest metal outlets because of this. Those PSP outlets looked like the best. I wonder why they stopped selling their products? Pinnacle or whatever? PSP

 

[SlowE93]

I say if you can use the stock outlets....there should be no difference. The bottle neck effect (if any) would be at the turbo outlet itself.

 

[SLOWESTN54]

I was always a bit skeptical of the gains from outlets. Especially when MMP's name was tied to them at the beginning: https://www.spoolstreet.com/threads/let-talk-outlets.2343/

Outlets are cheap, I say why not while you are in there. They aren't going to hurt anything and they can only help, as long as you don't burn a hole in them. I would suggest metal outlets because of this. Those PSP outlets looked like the best. I wonder why they stopped selling their products? Pinnacle or whatever? PSP

I'll run stock outlets for now, but ill be upgrading to a ARM intercooler with upgraded piping. With that my cold side will be optimized. After that I'll install outlets and do a before and after outlets dyno run

 

[RuskiRacer]

Would be some nice real life data to see

 

[Torgus]

At some point your piping becomes too small and starts to be a restriction. How much of a restriction? Who really knows(math). Personally I say match it to your TB size for as much of your charge pipe intact tract as you can. This is a general 'rule of thumb'. In our case with the n54 the TB is 76MM or 2.99''. I would go with an IC with 3'' in and out and 3'' CP from IC to TB. I see no reason to have a restriction at the IC inlet albeit it may be small, but the faster you get to 3'' the better imo. That also happens to be exactly what I run I step up from the Precision 6466 outlet to 3'' over 1 foot of pipe that then connects to my 3'' inlet on my IC(VRSF Race 7.5'') inlet.


According to Corky Bell, Maximum Boost page 61: 304 MPH or 0.4 mach is the point at which airflow meets increased resistance (drag) and flow losses are experienced as well as increased turbulence, if I recall correctly(might be off by 1 page)

0.4 mach = 304 MPH

2" piping
1.57 x 2 = 3.14 sq in
300 cfm = 156 mph = 0.20 mach
400 cfm = 208 mph = 0.27 mach
500 cfm = 261 mph = 0.34 mach
585 cfm max = 304 mph = 0.40 mach


2.25" piping
3.9740625 sq in = 1.98703125 x 2
300 cfm = 123 mph = 0.16 mach
400 cfm = 164 mph = 0.21 mach
500 cfm = 205 mph = 0.26 mach
600 cfm = 247 mph = 0.32 mach
700 cfm = 288 mph = 0.37 mach
740 cfm max = 304 mph = 0.40 mach


2.5" piping
4.90625 sq in = 2.453125 x 2
300 cfm = 100 mph = 0.13 mach
400 cfm = 133 mph = 0.17 mach
500 cfm = 166 mph = 0.21 mach
600 cfm = 200 mph = 0.26 mach
700 cfm = 233 mph = 0.30 mach
800 cfm = 266 mph = 0.34 mach
900 cfm = 300 mph = 0.39 mach
913 cfm max = 304 mph = 0.40 mach


2.75" piping
5.9365625 sq in = 2.96828125 x 2
300 cfm = 82 mph = 0.10 mach
400 cfm = 110 mph = 0.14 mach
500 cfm = 137 mph = 0.17 mach
600 cfm = 165 mph = 0.21 mach
700 cfm = 192 mph = 0.25 mach
800 cfm = 220 mph = 0.28 mach
900 cfm = 248 mph = 0.32 mach
1000 cfm = 275 mph = 0.36 mach
1100 cfm max = 303 mph = 0.40 mach


3.0" piping
7.065 sq in = 3.5325 x 2
300 cfm = 69 mph = 0.09 mach
400 cfm = 92 mph = 0.12 mach
500 cfm = 115 mph = 0.15 mach
600 cfm = 138 mph = 0.18 mach
700 cfm = 162 mph = 0.21 mach
800 cfm = 185 mph = 0.24 mach
900 cfm = 208 mph = 0.27 mach
1000 cfm = 231 mph = 0.30 mach
1100 cfm = 254 cfm = 0.33 mach
1200 cfm = 277 mph = 0.36 mach
1300 cfm max= 301 mph = 0.39 mach


Then you go here as an example to do some math:

Calculator: Horsepower and air flow

main personal website for Greg Raven

www.gregraven.org

Read more about it here: https://www.dsmtuners.com/threads/how-much-will-different-sized-intercooler-piping-flow.356270/

This explains it ok, but rather simplified:

You can do all the math and calcs etc. to find out how much you need at a given HP. Or just go 3'' and be done. 3.5 or 4'' is overkill for the N54 and would be a PITA to fit. There is also the limitation of the stock Tb at 3''. 3'' is as large as you can go without cutting things up and getting creative. People often use too small piping and get away with it mind you, but it is not 'ideal'.

In theory larger piping takes longer to pressurize. In real life you are not going to notice it. Unless you went from something WAY too small to something too large. like 2'' to 4'' over the entire intake tract after the turbo(s).

In other words: Give her the ol 3 inches!

Edit: All this said you can get by running a larger turbo, having more AKI, etc. Plenty of people make good HP on other platforms, and ours, with 2.5'' and even smaller. Plenty of platforms make monster power on a 3 or 3.5'' LS for instance. But when it is easy to run 3'' for most of the charge piping on an n54, why not? The cost difference is minimal.

Edit #2: Yeah, get outlets.

 

[Torgus]

I'll run stock outlets for now, but ill be upgrading to a ARM intercooler with upgraded piping. With that my cold side will be optimized. After that I'll install outlets and do a before and after outlets dyno run

If you can take the time to do a dynojet dyno before and after installing the outlets and provide logs for each run that would be great! Only real way to quantify any gains imo. No retune in-between the dynos.

You might consider doing the outlets while you are in there. Only because it is much easier to do it once while you are installing the turbos and you are already in there with the subframe out etc. Lots more room when everything is put back together. But...then we don't get the dynos showing the gains.

 

[SlowE93]

If you can take the time to do a dynojet dyno before and after installing the outlets and provide logs for each run that would be great! Only real way to quantify any gains imo. No retune in-between the dynos.

You might consider doing the outlets while you are in there. Only because it is much easier to do it once while you are installing the turbos and you are already in there with the subframe out etc. Lots more room when everything is put back together. But...then we don't get the dynos showing the gains.

Agreed.
@N54_Destroyer
Take your time and give us the data. My guess is it won't do much good, but would love to see if I am wrong.

 

[SLOWESTN54]

@N54_Destroyer

Your really wishing this into existence , if my motor blows I'm borrowing yours forever

 

[martymil]

I've done the testing years ago and the data is available do a search on google, nothing new.

And yes the inlets and outlets do make a difference especially in the midrange and somewhat up top
and as the turbos get bigger the stock inlets become an even bigger restriction

VTT inlets gains on a BMW 1M Stock Turbo - JB4tech.com - International Turbo Tuning Discussion

VTT inlets gains on a BMW 1M Stock Turbo N54

www.n54tech.com

 

[martymil]

Inlets and outlets will not give you extra power, they get rid of bottlenecks which lower your WGDC.

You can run a higher WGDC and make the same power but your turbos life expectancy is greatly reduced.

 

[SLOWESTN54]

I've done the testing years ago and the data is available do a search on google, nothing new.

And yes the inlets and outlets do make a difference especially in the midrange and somewhat up top
and as the turbos get bigger the stock inlets become an even bigger restriction

VTT inlets gains on a BMW 1M Stock Turbo - JB4tech.com - International Turbo Tuning Discussion

VTT inlets gains on a BMW 1M Stock Turbo N54

www.n54tech.com

Didn't show up on my google. Also aren't rhd cars way more restrictive. So you should have seen a way bigger gain then LHD cars. And in that test it seems that you tested multiple things in one go.

 

[martymil]

Didn't show up on my google. Also aren't rhd cars way more restrictive. So you should have seen a way bigger gain then LHD cars. And in that test it seems that you tested multiple things in one go.

In this test the only difference was inlets as I already had dp's and outlets.

 

[martymil]

On lhd outlets aren't a real restriction so by fitting inlets your wgdc will drop and the turbos will have an easier time
making boost and substantially lower the heat output which will give you a few extra ponies but nothing that can be felt.

 

[martymil]

Ok went back through my notes in that test it was inlets and outlets that where changed but outlets do nothing
for the car without inlets on RHD as the inlets are the restriction.

Those outlets where still a restriction compared to whats available today on RHD, the LHD outlets still outflow the factory modified
ones that where on this car at the time.

So when you change the inlets you should see a healthy drop in WGDC on LHD and lower your heat output going to your IC
which will be very beneficial especially in hotter climates.