Tuning vl37 -> vl36, adjusting boost pressure

[deta]

Hello,

Actually i have vl37 + remap. The map tries hold the pressure 1 bar as much as the turbo can. Of course its falling at higher rpms. Now its about 140 hp (@5000rpm) and 250nm (@2500rpm).
I bought a vl36 a few weeks ago, now im going to install. :slayer:
If i am right the new turbo will hold the 1 bar pressure longer, maybe to 5500 rpm. Sounds great, but i need some more power. Once i tried vl37 with 1.5 bar pressure and it was very cool but unsafe, so i undid the map to 1 bar.
What pressure can vl36 tolarate for everyday using (not racing mode...)? According some sites it can tolarate 1.5 bar at overboost and can boost 0.9 bar at ~5500-6000 rpms. How safe this? What other parts could be weak link? Main goals: 165-170 hp / 280-290 nm - safely.

What is your opinion?

 

[ChrisUK]

Most people use an upgraded actuator to hold boost longer. Don't see why you'd need to swap turbo (unless it's at the absolute limit?).

 

[deta]

hello unix admin mate

i swap turbo becase vl37 cant hold 1.5 bar safely, neither can provide ~170 hp.
btw, tell me about that upgraded actuator (type, manufacturer, etc)? maybe i will swap the vl36 actuator if you recommend. actually im collecting infos to build a dynamic, reliable and safe config.

 

[DlightSwitch]

Hi,

I have the VL36 on mine, and my boost gauge shows 22PSI (1.55 Bar) overboost, and usually about 17-18PSI peak normal boost.

Been safe now for 5-6000 miles with no problems.

I also have a forge actuator (not installed yet), because it has a stiffer spring for the wastegate, and will hold the boost better, because at the minute when I floor it, overboost comes in at 22PSI, then drops down to about 14-15PSI by the end of the rev range.

Some people also change the boost sensors to the abarth SS ones, because supposedly they can read the pressure faster and give a better rolling road graph.

 

[deta]

Good to read these experiences.
If everything will go fine then the next phase (after ~5000-10000 km with vl36) to replace sensors and actuator, but not at the same time. If something wrong, it's easier find a bug in the system.
Boost sensors: Yeah, I read about it from benpunto from an older thread: re-circ boost sensor, manifold boost sensor, "T looking Actuator" sensor. Not cheap at all...

And what about the exhaust system? With these modifications should i replace or make some modification? I read that some people replaced to SS exhaust, and fitted decat downpipe, but to be honest, i dont want to if not necessary. Now i have stock exhaust and cat.

And i'm not sure that the stock air filter wouldn't be enough to serve vl36.

 

[GymJunkie]

check out my motors thread, IMO the best place and best way to make a custom air intake if you cant get hold of the GSR kit (which nobody can) you also would need a cat back exhaust system either 2 1/4 or 2 1/2 inch diameter

 

[TallTom]

Hi,

I have the VL36 on mine, and my boost gauge shows 22PSI (1.55 Bar) overboost, and usually about 17-18PSI peak normal boost.

Been safe now for 5-6000 miles with no problems.

I also have a forge actuator (not installed yet), because it has a stiffer spring for the wastegate, and will hold the boost better, because at the minute when I floor it, overboost comes in at 22PSI, then drops down to about 14-15PSI by the end of the rev range.

Some people also change the boost sensors to the abarth SS ones, because supposedly they can read the pressure faster and give a better rolling road graph.

The boost will drop off near the end of the range anyway, the problem is the engine is breathing quicker than the turbo can keep up with, even in my abarth depending on gear it will drop off towards the end. Exceptions are if im thrashing it in 2nd/3rd gear and the revs rise quickly enough that by the time I change it has only dropped one or two bars(not pressure wise) on my inbuilt boost dial

 

[DlightSwitch]

Good to read these experiences.
If everything will go fine then the next phase (after ~5000-10000 km with vl36) to replace sensors and actuator, but not at the same time. If something wrong, it's easier find a bug in the system.
Boost sensors: Yeah, I read about it from benpunto from an older thread: re-circ boost sensor, manifold boost sensor, "T looking Actuator" sensor. Not cheap at all...

And what about the exhaust system? With these modifications should i replace or make some modification? I read that some people replaced to SS exhaust, and fitted decat downpipe, but to be honest, i dont want to if not necessary. Now i have stock exhaust and cat.

And i'm not sure that the stock air filter wouldn't be enough to serve vl36.

Yeah best to do it in steps, more rewarding as well as you'll feel the difference after each step. You'd definitely get better gains with a bigger diameter catback exhaust as GymJunkie said, up to about 2.5" max. Decat will also help you get better gains, but it's not necessary.

Yeah the stock air box and filter will be quiet limiting, you're best making your own induction kit as said in the above post, or just getting a forge kit as they have good gains as well.

The boost will drop off near the end of the range anyway, the problem is the engine is breathing quicker than the turbo can keep up with, even in my abarth depending on gear it will drop off towards the end. Exceptions are if im thrashing it in 2nd/3rd gear and the revs rise quickly enough that by the time I change it has only dropped one or two bars(not pressure wise) on my inbuilt boost dial

Yeah I know but it should improve with the stiffer spring, because I am sure some of it is to do with the wastegate. We'll see when i fit it