Na plus Turbo thread

[Fiftycal13]

Hoping to get some gurus input on the dos and don'ts of converting an Na engine tune to Turbo.

Apart from enabling Turbo logic,importing fuel base and timing maps to suit positive pressure and removing timing from the borderline table and scalling which ever injectors you choose there seems to be no clear info on what the best way foward after this is.

Some information on importing speed density, vct, ect and torque maps, aswell as enabling cylair anticipation in which I have all experimented with varying results. 

My ute goes well hitting target lambda under load and knock free from 5-10psi boost.  Fuel trims are way out through which makes me think that I'll need to start logging cam angle, air mass data etc and start modfing the speed density maps.  I just can't see most workshops doing all this in there tunes or do they just relay on fuel trims?

Any advice foward welcome.

[dat111]

if you are using all stock parts. 

F6 typhoon add that speed density an cam timing, an then readjust fuel./timing  where needed. 

[Fiftycal13]

Hey mate nothing wild just a pulsar 3582 with exhaust, plazmaman stg 1 cooler,4 inch intake, 1000cc bosch injectors and walbro 350 pump,  waiting on a turbosmart drop in reg as my "4 bar" reg wasn't actually 4bar.

I've done what you have suggested but seemed to be way leaner down low with the turbo Airflow maps, even when my target map was set to rich.  I assumed that was because the speed density was out due to turbo eng lower compression. 

My thought was to blend both na and turbo speed density and cam maps to suit na comp with boost.

[Puffwagon]

Look at the tps ad count switchover to open loop. Halve the whole table to start with and adjust from there. This will be what's causing it to be lean down low when you're asking it to be rich. I've already discussed this on the forum, a quick search should show you the exact details.

[Fiftycal13]

@Puffwagonmate I have done bulk googling on the subject and did miss that, good info, as soon as my new reg is here I'll trial it.

Whats your take on other tables when converting na to turbo.  Obviously speed density and cam maps seem to be the minimum.  Others suggest torque management tables,  desired boost tables even without wastegate control enabled,  cyclair anticipation et etc?

[Puffwagon]

Either find a suitable strategy and flash the whole thing onto the pcm or tune a stock na file from scratch, making changes only where necessary.

On 2/6/2023 at 7:15 PM, Fiftycal13 said:

I just can't see most workshops doing all this in there tunes or do they just relay on fuel trims?

There's many different levels of tuna and even workshops can be dodgy as fark. There is a process for tuning correctly, most of it is already listed in the how to sections. Failing that there is a manual to purchase from PCMTec that should get you into the ballpark.

[Fiftycal13]

2 hours ago, Puffwagon said:

Either find a suitable strategy and flash the whole thing onto the pcm or tune a stock na file from scratch, making changes only where necessary.

There's many different levels of tuna and even workshops can be dodgy as fark. There is a process for tuning correctly, most of it is already listed in the how to sections. Failing that there is a manual to purchase from PCMTec that should get you into the ballpark.

Thats what I'm getting at as surely both speed density tables would be way out and need modifying.  If you flash factory turbo data for high comp eng it will all be way out.  I'm thinking blending both is a good start but not sure.  Surely there a forum members out there doing this not just tuning factory turbo engines.

Necessary changes is what I'm looking for there is no real how to on na to turbo conversions.  Things like cylair anticipation should we be using that,  torque management tables etc  Its been referenced that attention may need to be directed to desired boost tables with turbo logic turned on etc can't find any info on it just mentions from trawling through threads.

[Puffwagon]

No it wont be way out, just the timing will be, as well as other minor things, and the comp difference will mean frig all to speed density. Use a turbo speed density map as it is designed for it. You should only have to make minor changes to it. You said you don't have any knock so you should be in the ballpark there. You will want about 10 degrees of timing give or take at 10psi on an na engine. You mentioned your trims are out, this is likely from an injector scaling issue, if not then adjust the speed density slightly.

My turbo strategy has cylair disabled from factory. You can change the predicted torque if you like but realistically you can tune the car without changing it. I dunno if you have to have the desired boost table populated, try it with it at 0 and if it boost cuts then populate it with your approximate boost level. Also ensure the overboost (auF0296) number is set no higher than -5psi otherwise you'll have no boost safety.

Anyhow hopefully that clears up a couple of things. Ask some very specific questions for answers otherwise most of the time you may as well read the forum how to etc. At the worst you'll get an " I dunno" 🙃

Edited February 8, 2023 by Puffwagon

[Fiftycal13]

WOT my lambda is on target, although my STFT which I'm still logging even though 02 is disabled is adding up to 30% fuel.

Im assuming this is because I'm still using na speed density settings.

I tried  halving the OL TPS table as suggested with factory turbo speed density, variable camshaft and etc data agian just now but still way too lean down low.  Tried cylair settings aswell to no avail.

Unless I'm missing a setting or turning too much on as I'm copying over all settings under speed density, cam and throttle than I'm thinking I should blend na and turbo maps,  na low rpm load and boosted high mid to high rpm load and work from there.

Failing that potentially mod the turbo speed density to match na down low.

Either way in my application unless Im missing something it doesn't seem like jsut loafing speed density, cylair or OL tps tables will work.

 

[Puffwagon]

On 2/7/2023 at 12:26 PM, Fiftycal13 said:

waiting on a turbosmart drop in reg as my "4 bar" reg wasn't actually 4bar.

A 4 bar reg will read approx 3.5 bar with the vacuum hooked up. If you know that your fuel pressure is out, there is no point trying to tune except to get the vehicle mobile, especially when you intend to change the reg/pressure down the track. It's a headfark at the best of times, even when you know what you're doing.

But if you don't want to wait etc, just mod the speed density down low. Lower numbers are richer, higher is leaner. Fwiw I would start by a global change of 25% lower from 750 to 2500rpm, reason being it uses the 250rpm column for starting so you don't want to start flooding it, also a global change of this amount to that rpm will likely be closer to what it needs. Alternatively you can log the cam angle vs rpm and just change those rows, it's not as hard as it seems.

Post the tune, a log taken from the actual tune, not a log from a different tune, any other actual data you have and I can have a look at some stage. There might be something that sticks out.

[Fiftycal13]

I checked fuel pressure as my slopes where way off compared to what others had posted here and hp tuners forum and decided to investigate,  I assumed too much pressure as I had 350lph pump instead of the commonly used 255 pump.  During test I found 50 psi instead of 58psi at zero vac from a drop in 4bar reg.  I adjusted the pressure in the Injector dynamics xcel sheet and that data with the correct pressure was a lot easier to scale.  

My understanding is I'd make changes to the MAP at Zero Airmass table?

[Puffwagon]

auF0060 looks to be the SD table in a BA Na tune.