Tephra V7 and Grimmspeed EBC
 

hi Guys,

just wondering how the wastegate control works on this rom. The reason i ask is after installing this rom and the grimmspeed ebc, i can't seem to control the boost. I zeroed out main map WGDC,boost desired engine load and PSI, boost error correction load and PSI, wgdc under this load is 100% to 30 from 200. I still get about 1.3bar of boost. In stock form before the EBC i had 1.1, and this was confirmed during my dyno run few days back.

Any pointers on how this is creeping to 1.3 bar would be much appreciated. (and what other tables i should look)
PS: the stock boost controller was of the dual solenoid type, left the black solenoid plugged in the wiring harness but removed the boost/vacuum lines, the grey plug is on grimmspeed ebc.

ROM:96530706 -2004 EVO 8 MR

thanks


CJ

1.1 bar is way below the stock boost on the evo 8 MR.

I thought (I could be wrong) that it is 19psi stock, which is 1.31 bar. If I understand your post correctly you have the "WGDC=100% under this load" set to 200. That means that the BCS will stay fully closed (blocking pressure from the wastegate actuator) up to 200 load, which is quite high. That would be why you're seeing 1.3bar.

On my '04 evo 8 MR I have that value set to 100, so the ECU will switch to using the "Main Map Wastegate Duty" table after 100 load. I'm actually surprised you're only getting 1.3bar though. It could be that you're going over 200 load, the ECU is switching to WGDC control and setting it to 0 because that's what your base WGDC map says to do.

I'd advise setting your "WGDC=100% under this load" to 100, set your "Main Map Wastegate Duty" to 30 all the way and going for a logging run. Keep the BDEL and BEC tables cleared while you tune the WGDC table. You should install a MAP sensor for this, the stock boost gauge (assuming you have the 3-gauge cluster) is not accurate enough.

For reference, I've included my WGDC table for my stock 8 MR with a GM 3-port BCS, which should be similar to the grimmspeed.

Looks like I misread your post. You have a grimmspeed EBC, not just the BCS on its own. Shouldn't that mean that the ECU no longer controls the boost at all, and the BDEL/BCS/WGDC tables will have no effect at all because the EBC is taking care of it?

hi mate,


i was under the impression that if i plug in the ebc to factory harness plug(grey) that the ecu will control it through main map wgdc tables, bdel etc.


the grimmspeed ebc is a MAC valve with a OEM mitsi plug. Thought that meant i could control it via the ecu.... not sure what to do if thats not the case....


CJ

That sounds like a BCS (Boost Control Solenoid), not a EBC (Electronic Boost Controller).

A full EBC will have the BCS, a box with it that you have to wire into power and probably a boost gauge too.

http://www.grimmspeed.com/catalog/pr...roducts_id=145 is the BCS, which will be controlled by the car's ECU. Set the tables as I described above and try logging again.

ta, going for a run now, sorry about the ebc vs bcs muckup :lol:

I'm curious neuralcj, how did it go?

it went well i was too chicken to run anything more than 20% DC above 2750 rpm, had 100% until 2750 on all gears dropping off to 20% through to 7000 rpm. It worked as expected. I will attach the evoscan logs shortly. It spooled up quick and then tapered off quickly after hitting 1.3 bar around 3-4k. I intend to run the settings below tomorrow.




CJ

i've just included the build up of one instance, can't seem to post anything over 100kB compressed.....

OK a few things:

1. Log less things. The cable can only do a certain number of requests per second, so the less items you log, the more of the ones you care about you get. While you're tuning boost you really only need RPM, TPS, WGDC, KnockSum and your MAP sensor. It doesn't look like you've got a MAP sensor though, so you can turn that off.
2. Log a few back-to-back 3rd gear pulls from 2000 rpm to close to redline. Try to make it a flat bit of very quiet road (or a dyno). Basically the more data you can get, the better.
3. When you increase the WGDC table, do it in small increments (10%). You can do that easily by selecting the cells and hitting * in EcuFlash, then entering 1.1. Once you get close to your target boost, make changes in 1-5% increments (* 1.01 to 1.05).
4. Keep a very close eye on your boost gauge and if you start to overboost, back off.

Remember that in 5th & 6th gear you're in the spool-up rev range for much longer so the turbo has more time to spool up and overboost. You'll want to have a lower WGDC in those gears to compensate, and higher in 1st & 2nd gear (if you like wheelspin).

You might notice that I've also adjusted the RPM axis on my WGDC table as that gives me tighter control of when to to start bleeding pressure when I've reached my target boost. This gives me 100% WGDC right up to the moment it starts to overboost and then quickly bleeds it off, giving me a much faster spool up. You'll also want to gradually increase the WGDC towards redline, as you need more pressure to keep the same boost level the higher the revs get.

thanks mate, I ended up with a wgdc table which looks like below. It seems happy here but i think i can push these further, will wait for a wb02 before the next run. I now have to put this on the back burner due to other projects and work. Thanks again for your help.