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PostPosted: Mon Oct 29, 2007 8:47 am
by KillerKam12345

PostPosted: Mon Oct 29, 2007 10:29 am
by Freon
No. Still running the code. The weather is getting colder here and I'm watching the effects on the system.


PostPosted: Thu Nov 01, 2007 8:40 pm
by Dougnutz
I'm new to tuning scubies but I have spent a lot of time tuning Detroit iron. Mostly Vettes and F-bodies. Anyway I'm curious why you would want to run a VE system. In the domestic tuning everyone was going the other way. MAF systems seem to be more flexible to conditions. You are measuring exactly how much air is going in and can easily calculate the fuel needed for a target A/F. With Speed density approach, any change in the engines efficiency, from exhaust mods to aging cams will change the engines VE and require retuning in order to achieve Max output.

Don't get me wrong I respect the heck out of what you are doing. The effort is incredible and I look forward to seeing the code (if its ever posted ) ;)

PostPosted: Fri Nov 02, 2007 7:00 am
by rdtech
Nice work. :lol:

Re: Curious.

PostPosted: Mon Nov 05, 2007 2:37 pm
by Freon
Dougnutz wrote:I'm new to tuning scubies but I have spent a lot of time tuning Detroit iron. Mostly Vettes and F-bodies. Anyway I'm curious why you would want to run a VE system.

Here's a snippet from the FAQ I'm working on:
A. The purpose is to side step issues with the limitations of a MAF setup. The primary
issues are:
1. Stock and near-stock-diameter intakes will hit high voltage with moderate to large
turbochargers. A stock or stock-diameter intake with a large turbo is not adequate for this
2. Large diameter MAF setups are difficult to tune, and may never offer equal or acceptable
idle stability (i.e. stalling issues, hesitation, long tune times, extra troubleshooting)
3. Minor changes to the intake may cause unacceptable changes to the tune. This can require
retuning or at least ECU and wideband logging to confirm the changes are within acceptable
4. Even minor leaks can really screw up fueling on a MAF car. While SD doesn't eliminate
all problems with leaks, they're less of an issue. This is covered further later in this

There is also the benefit of being able to run both recirculating and vent-to-atmosphere
blow off valves with SD. There is no richness when the valve opens, no matter if the
air is being recirculated or dumped out of the intake system.


I really am still working on it. I've been running it on my own car for over 3 months. Right now I'm watching what affect cold weather has on it. So far so good. I'm getting it coded for the 2005 STI B10J for a local to use with an FP Green 8cm.

PostPosted: Tue Nov 06, 2007 6:10 pm
by mtcavity
Very nice work man! :D

PostPosted: Wed Dec 12, 2007 12:43 am
by mxturboracer86
any updates lately? I recently threw a big turbo kit my car and would be interested in trying this speed density set-up even if its not fully developed. :D

PostPosted: Wed Dec 19, 2007 8:01 am
by KillerKam12345
UPDATES!!!!!!!!!!!!!!! :D

PostPosted: Thu Dec 20, 2007 3:33 pm
by Freon
I'm testing blow through soon. The cold weather moved my fuel trims more than I expected with a draw through. Keep in mind IAT is in the MAF element, and temperature is key for SD calculations. I can compensate as the ECU already has a few maps to do so, but I want to fully understand this change and give advice to start.

It may not really be ready until spring, but I am still working on it. My car is still running it, 6-7 months later. I have made no code changes in 5-6 months, just tuning here and there.

PostPosted: Sat Dec 29, 2007 5:45 pm
by Porter

Great work!

Quick question... are you using an auxiliary intake air temp sensor?

PostPosted: Mon Dec 31, 2007 11:24 pm
Can you elaborate on the existing temperature compensation maps? What are they, are they in the existing ROM definitions, and so on...


PostPosted: Thu Oct 23, 2008 3:24 am
by unnefer
Heya Freon, just bumping this thread as I'm very interested in your progress.

I'm not 100% sure I understand exactly, so please bare with me, but will your patch (if/when it is released) negate the need to rescale MAF when making high whp?

So I wouldn't have to worry about passing 300g/s?

I have a GT30 and I'm currently hitting 290 without much effort and am about to go through the whole rescaling headache thing so I can turn boost up and make some decent power - but from what I understand, I run you patch and never have to worry :p

Anyhoo, any news on if/when it will be released?

P.S. WIll this work for 16bit ECUs?

PostPosted: Thu Oct 23, 2008 4:23 pm
by Freon
This is an old thread.

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