View Full Version : ECU Map


Peter Sawko
09-26-2003, 02:07 PM
There are a lot of anecdotal reports from RX8 owners that might indicate a "flip" to a less conservative ECU map dependent upon car mileage. Some owners report power and mileage improvements as the cars 'break-in". (I have to agree on the mileage but can't be sure about power.)

Is there any factual information from Mazda that confirms this?

RX-GR8
09-26-2003, 08:25 PM
not that i have seen.

mikeb
09-26-2003, 08:29 PM
thats what we all are waiting for
maybe we will get info at sevenstock

rotarymotory
09-30-2003, 11:32 AM
Big mystery. No real answers. Lots of speculation.

After approximently 600 miles my eight seemed to "open up". That is, it seemed to breathe and rev more freely and there is more power across the entire rev range. The two places I feel it most are: I can now easily park the car(slow forward and backing) with just feathering the clutch at idle without giving it any gas. This was not possible earlier. And in city driving if I mildly accelerate through first, shifting at around 5K, second pulls much harder than it used to. It kicks my head back. Nice.

I believe what happened is that the ECU has settled in and has leaned out the mixture. THe result is a better running engine and more power.

I also would like to speculate that this early rich mixture is a big part of the "horsepower" issue. As the car settles in it gets more power.

RM

RX-GR8
09-30-2003, 11:47 AM
Originally posted by rotarymotory
Big mystery. No real answers. Lots of speculation.

After approximently 600 miles my eight seemed to "open up". That is, it seemed to breathe and rev more freely and there is more power across the entire rev range. The two places I feel it most are: I can now easily park the car(slow forward and backing) with just feathering the clutch at idle without giving it any gas. This was not possible earlier. And in city driving if I mildly accelerate through first, shifting at around 5K, second pulls much harder than it used to. It kicks my head back. Nice.

I believe what happened is that the ECU has settled in and has leaned out the mixture. THe result is a better running engine and more power.

I also would like to speculate that this early rich mixture is a big part of the "horsepower" issue. As the car settles in it gets more power.

RM

but not everybody is reporting this after 600 miles. some still get lower MPG and the same power. thats the mystery.

GooOnYou
09-30-2003, 11:59 AM
Originally posted by mikeb
thats what we all are waiting for
maybe we will get info at sevenstock

When and where exactly is sevenstock? I assume its a large RX-7 meet.

wakeech
09-30-2003, 01:52 PM
Originally posted by GooOnYou


When and where exactly is sevenstock? I assume its a large RX-7 meet.

last weekend, at Mazda North America's headquarters in Irvine California.

check out http://www.rotarynews.com for reports and pictures (~400) on the whole event.

Peter Sawko
09-30-2003, 02:36 PM
I have read other posts describing a method of removing the various sensor inputs the ecu uses in order to get a "pure" dyno reading.

What troubles me about this approach is that if I where designing a system to protect the engine that depended on various sensors the first "safe mode" I would establish is one that takes effect when a sensor is down.

I'm not sure I understood all of the various posts as some seem to indicate actually removing the ecu from the equation. This also bothers me because it's the ecu that controls the engine enabling best performance when all systems say go.

Does this make sense? Granted I'm still very troubled at Mazda's responses. I'm also surprised that boostd7 has not been heard from since he made his declaration.

rotarymotory
09-30-2003, 04:13 PM
My best guess after reading miles of threads is that every RX-8 will not flip the same at the same number of miles because everyone drives differently, uses different gas and lives in different climates(not to mention at different altitudes). Your mileage will vary GREATLY depending on how you drive. I can induce a 30% swing in MPG with driving style. So can anyone.

It's clear that the way the car was tested to obtain the mileage numbers is not the way most people will drive a rotary. I live right downtown in a large city. I make lots of trips under 2 miles and there is ALWAYS traffic. On the hiway, I drive fast at high revs. My mileage is 12.5 to 15. I know I can do a tank at 10 (I don't want to drive it THAT hard). And I could do one at 18, at least( but I don't want to drive it that soft). If I lived out in the country or wanted to take a long lazy trip, I could drive into the 20's.

If you can buy ANY car and actually get the MPG on the sticker, you're driving too conservatively for my tastes.

Like it says, the number is only to be used for comparison.

RM

nk_Rx8
10-01-2003, 01:18 PM
Originally posted by Peter Sawko
What troubles me about this approach is that if I where designing a system to protect the engine that depended on various sensors the first "safe mode" I would establish is one that takes effect when a sensor is down.

I have read the threads about the testing you are referring to. And at least in one case, the testing was done with a GTech. So if this true, than the numbers you get with sensors disconnected would be lower than when the car was untouched. But, it seems that the numbers were the same when stock untouched vs sensors unhooked while the car was running and also the same when sensors were unhooked while car was off and then restarted. So it seems that either it has no effect, or the ECU is in protection mode permanantly.

JaxFL_RX8
10-01-2003, 01:28 PM
Originally posted by Peter Sawko
I have read other posts describing a method of removing the various sensor inputs the ecu uses in order to get a "pure" dyno reading.

What troubles me about this approach is that if I where designing a system to protect the engine that depended on various sensors the first "safe mode" I would establish is one that takes effect when a sensor is down.

I'm not sure I understood all of the various posts as some seem to indicate actually removing the ecu from the equation. This also bothers me because it's the ecu that controls the engine enabling best performance when all systems say go.

Does this make sense? Granted I'm still very troubled at Mazda's responses. I'm also surprised that boostd7 has not been heard from since he made his declaration.

Oh my Gawd, they killed Kenn, er.., boosted7