how bad is the stock tune? forged motor

[chomper149]

How bad is the stock tune? its an 03.5 without a reflash of the ECU. so the richer one. But its forged but still on the stock tune. Boost has been upped to 15psi i believe. But is the stock tune so bad that you would never want to run it above 10psi regardless of if its built?
How bad do you guys think it could have damaged the engine if it has at all? Thinking it being extra rich wouldnt do as much compared to running lean. Still running the stock t25 just increased boost.

 

[js_protege_03dx]

did you lower the compression any?

 

[chomper149]

i havnt boughten the car, looking at purchasing it since im getting a good deal for the work done.
Says they are either CP or wisecos but he would need to check the papers. Also said hes going to do a compression check tonight

 

[jdwk]

The stock tune is alarmingly bad because the PCM will remain in closed loop until 4200rpm even under full throttle/boost. The PCM is also very slow to react in closed loop mode with a full second between cycles. A lot can happen in a second, and I've seen my fairly stock car hit 18:1 AFR before the PCM dumps an assload of fuel in when it switches to open loop.

The PCM also has no MAP based tuning, so it is slow to react from the MAF which is a turbo, and intercooler, and several feet of piping away from the intake. This often can cause backfires or nice puffs of unburnt hydrocarbons sooting up the tailpipe. It also is horribly inaccurate, and Mazda just dumped a ton of fuel in to be safe, so while AFR's before 4200rpms are dangerously high, they are extremely low after that point, robbing the car of power.

So while the stock tune is super rich and that is safe, it is closed loop I worry about. The forged motor buys you some insurance, but even a forged motor can't handle a full pre-detonation. I'd keep the boost low until you have at least a working piggy back in there.

 

[Installshield 2]

The stock tune is alarmingly bad because the PCM will remain in closed loop until 4200rpm even under full throttle/boost. The PCM is also very slow to react in closed loop mode with a full second between cycles. A lot can happen in a second, and I've seen my fairly stock car hit 18:1 AFR before the PCM dumps an assload of fuel in when it switches to open loop.

The PCM also has no MAP based tuning, so it is slow to react from the MAF which is a turbo, and intercooler, and several feet of piping away from the intake. This often can cause backfires or nice puffs of unburnt hydrocarbons sooting up the tailpipe. It also is horribly inaccurate, and Mazda just dumped a ton of fuel in to be safe, so while AFR's before 4200rpms are dangerously high, they are extremely low after that point, robbing the car of power.

So while the stock tune is super rich and that is safe, it is closed loop I worry about. The forged motor buys you some insurance, but even a forged motor can't handle a full pre-detonation. I'd keep the boost low until you have at least a working piggy back in there.

Is that an MSP ecu specific thing? When messing around and testing my factory P5 ECU years ago, it would only switch into closed loop until about 3500 rpm...and only partial throttle...one of the biggest reason the NA protege's were so ridiculously bad in stock form; AFRs in the 12 to 11 range in almost any condition under full throttle....and, at least with the equipment we had to test it...we couldn't get it to remain in closed loop under WOT at all...

but i never messed around with an MSP ecu, so good information, thanks.

 

[2.0t03speed]

if he has a o2 clamp your tip in afr's will be fine. With all my mods and a 2871r @8-9psi my afr's are high 11's in topend w/ the stock Msp edu tune. I would look into getting some timing control stat if the afr's are decent.

 

[chomper149]

the maf was reloacted after the BOV if that helps out with the stock tune. But form my knowledge its been boosting up to 15psi on the forged motor 03.5 nonreflash. But he also says he barely boosts since it is his daily right now.
got compression tests at 195 all around. anyone think its damaged then? or probably good to go? only thing making me jump on this right away is the stock lsd thats still installed

 

[2.0t03speed]

the compression sounds good

 

[Carlinator]

Is that an MSP ecu specific thing? When messing around and testing my factory P5 ECU years ago, it would only switch into closed loop until about 3500 rpm...and only partial throttle...one of the biggest reason the NA protege's were so ridiculously bad in stock form; AFRs in the 12 to 11 range in almost any condition under full throttle....and, at least with the equipment we had to test it...we couldn't get it to remain in closed loop under WOT at all...

but i never messed around with an MSP ecu, so good information, thanks.

The ECU is probably about the same, the difference is in the turbo piping - by the time the air mass starts getting sucked across the MAF, it's already been getting pushed into the intake manifold for some time. Add to that the fact that the boost gives more oomph to the pistons and spins the motor up a bit faster, and you can see why it hangs on so long.

The car really should have been on a MAP-IAT setup from the beginning, due to its quicker response, but that's what happens when Mazda spends all their development time on suspension tuning and leaves the engine for last.

 

[chomper149]

heard the non-reflash was richer/ maybe it would be safer. and the timing was less advanced also better for higher boost. or so i read. If i grab it i plan on going back to stock wastegate for a while, fixing LSD and getting ssafc.
Anyone else see any real reason why i should def stay away from it? it was getting 190psi on all 4 faces cold too.
just wish i could find someone to swap the lsd for cheap! or id have this protege right now

 

[ND4MSP]

if he has a o2 clamp your tip in afr's will be fine. With all my mods and a 2871r @8-9psi my afr's are high 11's in topend w/ the stock Msp edu tune. I would look into getting some timing control stat if the afr's are decent.

Excuse my ignorance, but do that mean with an o2 clamp you can get fuel to richen sooner?

 

[ND4MSP]

My bad so after reading a bit the o2 clamp enables you to trigger open loop sooner. but what happens from there on out in terms of afr's for the average non big boost msp? pig rich as usual Sorry to thread Jack.

 

[2.0t03speed]

You run a vacuum line to it so it only triggers when it sees boost. Everything after it switches over is rich like normal

 

[Installshield 2]

The ECU is probably about the same, the difference is in the turbo piping - by the time the air mass starts getting sucked across the MAF, it's already been getting pushed into the intake manifold for some time. Add to that the fact that the boost gives more oomph to the pistons and spins the motor up a bit faster, and you can see why it hangs on so long.

The car really should have been on a MAP-IAT setup from the beginning, due to its quicker response, but that's what happens when Mazda spends all their development time on suspension tuning and leaves the engine for last.

Got it. And to be fair, we can thank Ford for the EEC-V ecu in North American 3rd gens...At that time Mazda only made OBD-I ecu's for their own Market; Ford made them for everywhere else...doesn't excuse the sensor layout though, only the computer's parameters...

Anyway, yeah, for NA purposes the ecu's biggest problem was the opposite for the Turbo setups...open loop comes in WAY too soon, and is way too rich, with completely retarded (pun somewhat intended) timing for an engine with such little dwell...With the extra piping and airflow of a turbo setup, it seems to create the opposite problem...

 

[ND4MSP]

You run a vacuum line to it so it only triggers when it sees boost. Everything after it switches over is rich like normal

Strange, that make way to much sense to run one of your content with bolt ons and a couple pounds more of boost. Yet I don't think many do.

 

[Carlinator]

Yeah we still get the pig rich tune in open loop, but we have the added bonus of that nice ultra-lean spike right before.The computer in closed loop is trying to add fuel to the boosted air to keep it 14.7:1, but between the long piping after the MAF sensor and the input lag from the O2 sensor it can't keep up, so the mixture runs way lean and you get detonation at WOT, then it falls flat on its face when it finally does switch to open loop.

 

[jdwk]

The O2 clamp doesn't trigger open loop. I really wish it did, but all it does is tell the PCM that the mixture is lean (0V) and add fuel.

While this works, it eventually ***** with the long term trims. Just click on an random page in the 120+ page SSAFC thread and you'll see someone complain about a tune that went bad.

It was so frustrating trying to figure this phenomenon out but I had the AEM FIC and could actually monitor my fuel injector duty cycle which helped explain it all.

That's interesting about the P5 going to open loop at full throttle. I always assumed the MSP tune was so bad because they couldn't change this behavior from the other proteges without extensive rework of the PCM and said, "ah **** it, we'll just keep the boost at 7psi and dump a bunch of fuel in later."

 

[ND4MSP]

Ic. But isn't the o2 clamp and rrfpr setup pretty consistent though when p5 guys that don't choose to go piggyback or standalone. diff ecu though obviously

 

[jdwk]

I wouldn't think the ECU was that different. When I was essentially running an O2 clamp with the AEM FIC it was consistent, but I ran into ignition cut after a week of running just fine. With the O2 clamp, the PCM will keep adding more and more fuel and the trims eventually max out at 25%. That means if the PCM calculates a normal 75% duty cycle based on the MAF signal then it cuts the ignition.

I'd imagine the P5 guys with just an O2 clamp and FPR also need a MAF clamp.