I think that the hole point of doing a ECU reflash is having the ECU whant you want it to do; not depending on what it decides... Any way my tought was on running closed at idle and somewhere between 25-30% (for when your are just crusing or driving low speeds) of throttle inestead of 75% as in stock.

I agree with you hackish, from what I have seen, once the engine is at operating temp; it will only be affected by thottle position no matter if you are @ low/high rpm or vacuum/boost...

 

Absolutely the open loop/closed loop thing can be modified. I reverse engineered that routine quite some time ago. This is one of the major things that prevents the piggybacks from working correctly. Another thing is the way the electronics deal with the MAF sensor. It's quite neat actually - using 2 different modes to read the MAF at high airflow and low airflow.

 

how do you modify the open close loop thing?

 

+1

 

Will this work with an 06 ecu? I heard that they were different than the 04-05 ones...

 

Where do I put the +1? the input settings?

 

I haven't seen an '06 ECU yet. Maybe I'll see if I can find one for testing. I suspect it will work just fine.

 

ok thanks!, I'll wait for more info then

 

the only way to keep open loop on all the time is reflashing?

 

Yes. Adjusting the open loop settings can really only be effectively done with a reflash. For everything you try to trick it into staying in open loop there is a test to make sure your tricked sensor stays within certain parameters or it throws a check engine light.

Given all the checks and balances you can't even effectively run a piggyback - trust me I tried for a long time. The circuit inside the ECU uses a few tricks that switch the MAF signal to have a few levels of resolution. You can try using a resistor on it which is what I believe most piggyback manufactuers are using but in the cold, at low throttle and high throttle angles it ends up altering the readings. Ouch! This is why piggyback fuel trims are so erratic - the piggyback has no way of knowing when the ECU will switch the MAF loads.

There are a lot of things you can only do with reflashing. One very important thing I've found is raising the rev limit. Currently it's set at 6700 RPM but the car makes power well beyond that and you don't start to get valve float until 7400.

-Michael

 

7400 Sounds amazing. I've been curious as to how much we can raise our rev-limits. I can't wait until your reflashes are ready for mass production hackish!

 

Stock car, 7200 is a reasonably safe spot. I'm still working on springs and retainers so the head can be improved a little. I would have to do some tests on the stock rods before I could recommend reving higher than that but honestly I don't have time at the moment.

I have someone who asked for 7500 and he's been driving it for a while knowing the risks - nothing has broken yet but I have a case of beer on it not lasting the summer. Mmmm. Bleue Dry ( Last time I read his ECU he'd hit his rev limiter 85 times in a week since it was reflashed!

-Michael

 

Hack,

You really are the man...! How much time takes you to modify the ecu...30minutes..? So how much downtime I'll have if I have to send you my ECU for some custom setting?

 

Modding the ECU is not the time consuming part. Takes about 10 minutes. The time consuming part is the nearly 1000h of disassembly. It took a group of guys several years to crack the EVO ecu. I'm not quite as far ahead as them but almost and I'm only one guy. I figure I'll probably sell a mail-in reflash for about $450USD per unit. If you do that math, considering $20k or so in hardware and expenses, that means I've got to sell a LOT of them before I even get a paycheque.

I'd like to take on a few more beta testers but I feel that I have to contact the mods and such since it's only beta and I don't want to have to pay vendor fees to develop a product before it's really for sale. I will wait for the moderator's direction before publically offering any more beta spots.

You could easily pick up a scrapyard ECU and send that in so your car isn't offline.

-Michael