Unreal

Find a different tuner if they don't know how to deal with that. It is beyond easy.

Just do the proper scaling.

0Chuck CoW

You might get the engine to run, but you'll have lots of other problems.

As stated, you can do some injector scaling via a few different methods.

For anyone interested, I have close to 200 E40, E38, and E67 ECMs and can usually unlock your LOCKED or BRICKED ecm

call anytime if you need a spare ECM or yours becomes unusable.

I got the GOODS!
Chuck CoW

Indepth

Typically any type of FI C6Z I've seen has always been purely speed density tuned with the MAF disabled. FI applications inundate the MAF and extend beyond it's reading capabailities even in the more milder builds.

If your tuner is using a MAF tune on a FI build along with struggling with tuning for bigger injectors when it's been done many times over I think you might start the hunt for a new tuner.

EnginerdVT

He didn't say I couldn't go another route, but we responding to a recent car I was present for tuning on that was a 2011 z06 on the same blower setup. It put down 830rwhp on the factory MAF and had larger tables to use with the bigger Injectors. I was simply getting outside counsel for whether going SD was the right way to or whether there was an advisable way to stay MAF and scale my smaller injector tables. Thanks for everyone's input. Looks like I may be pursuing SD tuning with someone else who isn't remote for the setup.

As always I appreciate the knowledge on here. Looks like I might go Speed Density then. I was worried about weather changes and it running well on SD tuning.

Indepth

Speed density, to my knowledge, is really the only proper way to tune a force induction C6Z. I stand to be corrected if I'm wrong but everywhere I've read and tuners I've talked to have said any force induction based application for our cars vastly outpaces the MAF's ability to function properly.

Be sure whatever tuner you select for your SD based tune takes their time on the tuning. VE tables are hard coded and to make changes you'd need your own HPTuners software and interface. MAF based tunes adjust themselves based on the MAF reading and use the VE tables as a fall back. This is just another reason to make sure your tuner is local to you too if you need any touch ups.

Unreal

Stock maf is fine for 1200+

Stock ecu is fine for 1200+

EnginerdVT

So you recommend the scaling approach to keep the MAF?

Indepth

I've been told in boosted applications the airflow far outpaces the MAF. Can you elaborate? I'd like to understand further.

Unreal

I ran maf at 1200+
Jody runs a maf at 1000+

Maf limits depend on size of tube it is in. A stock card style maf will make 1300+ in a 4" tube. You can go to a 4.25 or larger if you need more.

Now if you stick it in a 3" tube, yah you may run out of maf range.

Indepth

Ah, so you're saying this is dependent on the intake's diameter surrounding the MAF - that makes sense to me then.

MTPZ06

Good info to know!

EnginerdVT

Ok. A&A claims a 4" intake tube so that should support. I'm worried about the injector issue but it sounds like it just means you have to fit less fidelity in the table to support a larger Injector, which sounds do-able.

Unreal

Just 1/2 the IFR and double stoich. Don't even really lose any adjust ability in the tuning.

There are some other advantages to a newer ECU, but for what you want, wouldn't deal with the hassle.

I have a 2009+ ecu sitting in garage waiting to go in, but haven't found the will power to do it just to read boost past 2.5 bar.

EnginerdVT

IFR stands for? Sorry I'm getting my education today. So it sounds like you can make these changes to offset and then use the tables as is, or is there a lot of background work to do in order to tune after that?

Thanks again for all the info. Unreal, if you want to discuss on the phone, I could use some reassurance on this before I pick a direction (SD or MAF tuning).

Unreal

Injector flow rate.

So if you have 100lb injectors you put them in as 50s, then double a few tables, done. No need to mess with ecu swaps, etc.

SD vs maf depends on your car/tuning. Still a fan of hybrid. Ran both. Like factory, SD works better at low RPM, taming out transistions, etc, but maf works great from 3500+ when air is flowing good. Do both like the factory.

If I had to choose only 1, I would do SD. Only reason I'm SD only is I like the upper pipe with no maf, so I don't even have a maf on my car.

Indepth

Bookmark this for future reference if you plan to learn more about tuning in general, it'll become a bible to you for a while.

https://www.hptuners.com/forum/showt...2-Acronym-List

IFR-Injector Flow Rate

Dan_the_C5_Man

Another real-world example of why it is good to keep the MAF in play..

Heading to Barber MP this Saturday, when I left my house at 5AM it was around 45 degrees. The temperature change coupled with a drop in elevation (I live in GA, track is in AL) I saw up to 14% positive LTFT's on the way there (typically they are at 0 or -2 ~ -3).

Throughout the day the temps rose to almost 80 degrees.

The point is, there are very good reasons for running the stock MAF / SD hybrid configuration - a lot of "tooners" (stole that one from MD) will do MAF-only tunes because they are too lazy to do the real work to map the VVE tables. The sad part is 90% of the folks that have these tunes in their car have no clue it is setup that way.

Indepth

This couldn't be more true, sadly those types of tuners run wild it seems.

You data logged your entire trip? Dedication right there.

Unreal

Dan is correct. Very few if any people try multiple tuners or know what they are missing. They get the car tuned, it makes power on dyno, drives ok, and they praise how awesome their tuner is and how he/she is the best. I've seen local tunes that are complete crap yet the owners were happy because they don't know better.

Indepth

Ignorance is bliss?