08 LS7 supercharged scaling gone wrong?

[bradyzq]

Hi All,

I have an 08 Z06 with an intercooled A&A Vortech supercharger kit, running MAP referenced 4 bar fuel pressure on ID 850 injectors, and a round 102mm MAF tube. Currently running the stock 1 bar MAP sensor, until the ZR1 piece arrives. I've not been into boost yet anyways.

It has ported heads and an aggressive cam, long tube headers.

We're aiming for 750-850whp on 94 octane pump gas.

Here's the problem: I entered the ID850 data in the stock tune file from this car. Then scaled EVERYTHING involving mass or torque unless it was maxxed out. I scaled it down 50%. The car started and ran on this scaled stock file MAF-only in open loop. But at around 3500hz, or once, at around 4700hz, the cylinder airmass doubles along with injector PW, but with no corresponding change in calculated cylinder airmass nor in MAF hz. The car then wants to die because it's flooding itself. A pending P0101 MAF performance code results. I don't get it.

So I thought I might have screwed up the scaling. I then went back to the stock file, entered the injector data, MAF-only stuff, forced open loop, halved the IFR, and doubled the stoich, and VOILA, it runs fine, with no MAF code.

I will exceed the 1.36g limit and the 512g limit with this build so I need to scale somewhere. I would like to work with the fully scaled tune, but there is obviously something wrong with it.

Can you see the error in my scaling?

Thanks!

[SultanHassanMasTuning]

you need to go custom OS to exceed the maf limit.

[realcanuk]

Agree. You need the 2bar OS. I run the same injectors at 725 rwhp. I didn't scale. I used the 2bar OS and doubled stoich and halved IFR.
From your description I'm thinking this is Steve's car? I'm looking forward to seeing it.

[bradyzq]

Agree. You need the 2bar OS. I run the same injectors at 725 rwhp. I didn't scale. I used the 2bar OS and doubled stoich and halved IFR.
From your description I'm thinking this is Steve's car? I'm looking forward to seeing it.

LOL!

Yes, it's Steve's! He mentioned a friend's car that was putting down 725. I guess I know who that is now....

I'm not convinced we'll hit the MAF hz limit, just the 512g limit. Scaling will fix that. I've done scaled cars before, but for some reason, on his, I must have gone too far, and scaled things I didn't need to. I think I gave myself carpal tunnel syndrome scaling that file.

I'd really like to keep MAF on this car for high flow resolution.

[realcanuk]

LOL!

Yes, it's Steve's! He mentioned a friend's car that was putting down 725. I guess I know who that is now....

I'm not convinced we'll hit the MAF hz limit, just the 512g limit. Scaling will fix that. I've done scaled cars before, but for some reason, on his, I must have gone too far, and scaled things I didn't need to. I think I gave myself carpal tunnel syndrome scaling that file.

I'd really like to keep MAF on this car for high flow resolution.

That's me !!I remember Steve in my driveway saying he just wants to put on a blower and get 600 hp for fun. lol... Yeah right.

I am not an expert tuner. I tune my own car because I like playing around and have learned a few things about E38's along the way.

You really need to upgrade to the 2 Bar OS. That will extend the 512g limt to 1024g. There are other good features too, like being able to set the fans to come on sooner. I never scaled because I have an automatic and I hear scaling wreaks havoc on the shifting. I was running MAF only up until about a month ago and that worked perfectly too, so the maf is not an issue.

If you really need to scale, and don't get the info you need here, let me know and I can put you together with the guy who tunes and helps me. He knows of steves build already and knows you guys too I think. He has scaled a bunch of these so maybe can help, and I know he would be happy too.

[bradyzq]

Thanks!

My plan was to use the stock OS, use a 3 bar ZR1 MAP sensor, and Bluecat's VE tool. For now, MAF only will have to do. The idle is quite raucous though responsive enough. It can only get better with dynamic airflow enabled.

Your car is a real torque monster. Steve's will likely be more of a screamer.

[realcanuk]

I'm sure that thing will be crazy and you will get it running great. Your post reminded me.. Another benefit of the 2 bar OS is it gives you real Ve tables and you don't have to deal with bluecats tool.
Good luck and keep us posted on results.
Jody

[bradyzq]

Upon further searching, as I suspected, I may have gone overboard on scaling.

I DID scale idle airflow, which seems to have been an error (DSteck says).

I DID NOT scale throttle area, which I should have, according to Greg Banish, though I don't think he mentions it in his DVD.

I'll try those today, first unscaling idle airflow only, then adding in the throttle area scaling.

[realcanuk]

Upon further searching, as I suspected, I may have gone overboard on scaling.

I DID scale idle airflow, which seems to have been an error (DSteck says).

I DID NOT scale throttle area, which I should have, according to Greg Banish, though I don't think he mentions it in his DVD.





I'll try those today, first unscaling idle airflow only, then adding in the throttle area scaling.

Working sundays ??? Nice... hope that works. 2 bar upgrade !! Dont be stubborn. lol. Wheres the shop... I want to see that thing !!

[bradyzq]

But stubbornness is an integral part of my personality!

Actually, when looking at available OS upgrades on this car's PCM, 2 bar is the only choice, but is described as SD ONLY, something I'd rather avoid. WHEN , not if, the scaled tune works I will have effectively added 1024g MAF and 2.72g load axis limits.

[realcanuk]

I'm not at my computer now so not sure which one, but its not SD only. Called 2.5 bar if I remember right. Curious how your way will work out. Keep us posted.

[bradyzq]

OK, update. So far, with the idle airflow scaling removed, the car idles fine, and is much better, BUT, it still doubles the fueling suddenly at about 4000hz, which doesn't happen when halved-ifr-doubled-stoich is used instead. The event occurs at the end of the log.

[c.u]

This is what you get when you use the 2 Bar OS. You can you use it in blended mode,Maf only or SD. Its up to you. Well i add this just for otheres. http://files.hptuners.com/support/De...alkthrough.swf

[bradyzq]

New update: Well, I went back to the fully scaled tune, including idle airflow, and scaled the ETC scalar down by 50%. And it seems to work!!!

No more doubling of airflow and fueling (but not MAF hz) at 4khz ish.

[bradyzq]

c.u.,

Thanks. I became aware that it wasn't really a 2 bar OS awhile ago.

It wouldn't kill Bill (heh, heh) to update the enhanced OS button in the editor to reflect what it actually is you'd be upgrading to, though... It still shows 2bar, not 2.5bar.

Anyways, so far, now that I've cut the ETC scalar in half on a fully scaled tune, it seems to work.

[realcanuk]

New update: Well, I went back to the fully scaled tune, including idle airflow, and scaled the ETC scalar down by 50%. And it seems to work!!!

No more doubling of airflow and fueling (but not MAF hz) at 4khz ish.

Brady,

I am looking at the tune, not to criticize, but because I am interested in scaling, and the proper way to do it. I haven't looked at much yet but want to point out what might be an oversight. You have PE delay set to 5000 rpm. Maybe its something I don't know, but it would seem to me that just cant be right ??

Jody

[bradyzq]

No worries!

You're criticizing GM, not me! I haven't touched that. It's basically a stock tune, scaled by 50%, running open loop, with a few other tweaks that may or may not work. But that PE delay is stock, for sure.

[realcanuk]

No worries!

You're criticizing GM, not me! I haven't touched that. It's basically a stock tune, scaled by 50%, running open loop, with a few other tweaks that may or may not work. But that PE delay is stock, for sure.

I get that its stock. What I am getting at is you definitely want to be in PE when going into boost, and with it at 5000 you won't. I don't think its safe to leave it like that on a boosted car.

[bradyzq]

It won't be left like that. I posted this up pretty much stock because the scaling glitch didn't let me get any further than pretty much free-revving.

Now things are moving along...

[C5 2000]

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