Hi Al,

I've had my car on the dyno today and ran into some problems I hope you (=a flash) might be able to help with. I have an '05 EVO MR with a 3" turbo back custom exhaust + HFC. The exhaust has been on the car for a good two weeks+, so the ECU had lots of time to adjust to it. When I first put it on, it felt noticeably different - buttdyno said about 15 hp maybe. However, when I put in on the dyno today, it showed no gain - none, zip, zilch, nada. I'm comparing data from the same dyno, gas, weather (pretty much), and calibration as the baseline.

Tim (the guy running the dyno) told me that on newer cars the ECU is so smart, it will actually "tune-out" any mods if it can, and return the car to stock specs if possible. So we disconnected the battery to reset the ECU, and sure enough started to see some gains. After 3 runs it showed ~15 hp as expected.

Now I'm trying to decide if I should flash this week, or get an intake first. So, my questions are:

1) would a flash cure this "tuning out" behaviour of the ECU?
2) with just the 3" turbo-back how much whp gain can I expect?
3) with the exhaust + Apex'i intake how much can I expect?

Also, if you have any other observations about the curves please feel free to share - thanks! The original baseline is posted on http://www.evolutionmr.net/forum/viewtopic.php?t=86

Below is the dyno data with the exhaust on (after resetting the ECU), vs the baseline. The exhaust has v-band clamps on the HFC, so I tried both the HFC and a test pipe. What do you think?

 

nice!!!

 

Thanks for the very detailed question its very helpful for me to give you some useful data

First of all - lets look at the boost chart, the MR has a propensity to spike up the boost when it spools up and then fall down. I found when I was out tuning on 91 octane that even the stock ecu tune would knock badly when then boost spiked so high. They are trying to get the turbo spooling quickly - give the customer a nice kick in the pants - a nd then pull down the boost quickly before it recahes peak trq and detonates like a pop corn machine on low octane. It leaves something to be desired as it makes for a uneven power band . I prefer a smooth turbine like board power band.

My suggestion is a Hallman Manual Boost controller which can very effecively regulate your boost level at a steady 20 psi max falling to 18.5 at red line./a

Now lets move on to a.f ratio - they keep the a.f tagets kind of lean at 3400 to 5100 basically going from a high 11 to a low 11 a/f ratio. The problem is that the lean part of the curve falls in that boost spike area at 3200. That boost spike could prob use a richer a.f ratio than that in that area.

The rest of the power band is pig rich and for good reason as they are trying to keep that 91 octane from knocking .

Even with that rich a/f the car still shows a fairly significant area of knock activity at 5250 rpms - you can see this in the pronunced dip in that area of the tq and whp curves.

I think with ethe combination of a well functioning manual boost controller and a tune designed to smooth out the power band while avioding any knock activity you will find a very consistant tune,

Let me give you of an example of a MR with only a MBC, fuel pump and flash - stock exhuast

This was on a MR with totally stock exhuast and intake - only fuel pump, MBC, and flash - a much different result than on your sheet - smootrher and stronger




Finally as can be seen by the almost two identical runs above - if you set up your flash tune properly - then you will not have any problems with the tune moving around of changing itself over time. In fact it will hold for years.

 

Hey Al,

At the NW Evolutions meet this past weekend, we all talked about seeing how many ppl would be interested in getting a tune from you. Well I think the response was HELL YEAH, but I was going to find out first how many ppl do you need for us in the NW to get you up here to do such a thing??

Thanks in advance!!

Joey

 

4 or 5 firm guys and I am there !

 

Hi Al,

thanks a bunch for the detailed response - I'm an (aerospace) engineer by training myself, and like to tell people "engineering is done with numbers, anything else is just an opinion" - so the data you posted is much appreciated . Also, I'm in the same club as Jo & Joey (Northwest Evolutions), so we'll lobby and try to get a group together for tuning. Now back to the regular program....

If I understood you correctly, the ECU is "tuning out" the gains from the exhaust not because of some magic code that wants to keep the car at stock spec, but to avoid knocking (BTW I was running on 92 gas), thus it is not a change in the ECU for the '05 cars, but the change in the turbine that causes this behaviour vs. the earlier years?

On the MBC - I understand what you are saying that it would provide a steadier boost setting. However, I'm thinking in its stock configuration, the car's ECU acts as an Electronic Boost Controller, right? Shouldn't your flash then be able to adjust the logic for that "EBC" to achieve the same smoother boost curve, but retain the advantage of quicker spool-up etc you get from an EBC vs. an MBC?

Lastly, I'm much more of a (curvy) track racer than a drag racer , so my goals for the car are more focused on quick spool up and smooth power delivery than ultimate peak output - although bragging rights are always nice too of course . Experience has also taught me that "every mod is another noose to hang yourself with", which makes the idea of using the stock ECU for boost control appealing to me. So with that in mind, would you still recommend the MBC or could I achieve what I'm after with a just a custom tune?

Thanks!

 

wow, subscribed. I'm totally new into the evo scene, but lookin for a 9 when they come out in a year or so. That dyno with the pump, MBC and flash is nothing short of amazing.

 

Al - 5 days and still no package . Can you dig up that tracking number or let me know what date to expect the ECU back? If I keep working from home to be there when the FedEx guy shows, I'm going to get in trouble soon.