LQ4 running SD 2 bar.

[bsh]

Hi,
I am trying to help a guy tuning his twin turbo LQ4 using HP Tuner 2.24 and tune as speed density (SD) running no MAF. I have no experience with HP Tuner so I am wondering why the Fuel table show kpa as load but Spark table shows g/sec as load? How to setup spark table load axis as kpa instead of g/sec since he is running mafless?

Thanks
Ben Stian

[steve smith]

pretty sure you should see map to adjust ve table.

[bsh]

Hi,
Yes I see VE table (fuel) with kpa as load which is fine. But I cant see the Spark table with kpa as load on the y-axis, only g/sec which I believe is useless since he dont have any maf to measure air flow. All other standalone systems I have tuned with speed density ( map sensor, no maf) use manifold pressure as load axis. I am sure it is only me that dont know to setup the right axis in spark table...

Thanks

[wasyl]

bsh i ran in to same problem ant there is no solution to that at the moment, you have to figure it out this way, all SA systems are made different way and are more user friendly then just interfaces for stock ECM/PCM cars, but i to woner why don't they to do routines to read MAP as load on spark tables

best regards

[bsh]

Hm strange...
So you have to alter engine displacement and inj cc in a way to fool the ecu thinking it flow less air so it doesnt outflow the Spark Table g/sec? Maybe someone can explain in detail for a newbie to do this the correct way?
There is alot of high hp cars running HPTuner, so there must be a solution for this issue.

Thanks

[wasyl]

well, they way round is to use dataloggine on HPT scanner, there is a table for spark to log in MAP vs RPM mode, but You can edit that to g(grams) vs RPM and see what maximum spark goes in what range and then You will know where to adjust spark on base table or on addes from like IAT, ETC and so on.
some pic where to change on scaner form map to g(grams)

1.jpg

2.jpg

3.jpg


On values you have input all row values you need separated by SPACE
4.jpg

best regards

[wasyl]

on step 3 you can also choose VE/MAP/MAT Cylinder Airmass if MAF was deleted.

best regards

[schpenxel]

Simply change the axis to whatever you need it to be to match the VE (or whatever) table you're working on.

The default config is merely a starting point

[bsh]

Thanks guys

[MikeOD]

Hm strange...
So you have to alter engine displacement and inj cc in a way to fool the ecu thinking it flow less air so it doesnt outflow the Spark Table g/sec? Maybe someone can explain in detail for a newbie to do this the correct way?
There is alot of high hp cars running HPTuner, so there must be a solution for this issue.

Thanks

Yes, if as you adjust the VE table to get commanded fueling to match up to real world fueling you find that you're running out of axis on the spark advance table, you need to scale the tune, so you change the injector flow rate table and VE table by the same % to make the computer think there's less overall mass of air...this gets you resolution back in the spark table.

The newer computers have an adjustable axis for spark advance, so you can just change that to get the resolution you need, but the PCM's that came with LQ4's don't have that capability.

[schpenxel]

There's more to it than just the IFR and VE tables. Everything using airflow has to be scaled.