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10 psi = 10psi yes. But your cfm of air flowing through the afm will ring alarm Bells with your stock ecu.

A smaller turbo closer to stock you might get away with but the T04 will flow much more air at 10psi. Hence the car responding bad

Hey mate, I get the impression you are being serious... So I will give you as best a response as I can.

The above guys are actually correct. Your problem is your ECU. The ECU is not able to cope with the change to the new turbo.

To put it simply, pressure (boost) and volume (actual amount) are not relevant to each other. That means that 10psi from the stock turbo will be far less compressed air (power to be made) than 10psi from the T04Z.

Your car is literally a ticking time bomb, and I can assure you that if you persist you will blow the motor very soon.

You will need the following items ASAP:

700cc+ injectors

A good fuel pump (if you dont have already)

A map based ECU (running a Z32 AFM wont cut the mustard for a T04Z)

To all experienced forum members, can you please simply +1 my post if you agree. I believe the guy is being honest and is not long off wasting 3 years of hard work on his car and motor.

GL

thanks very much, thats all i needed to know. I was being serious. And as the first injected motor iv built, the electric side is all new, what is a good map ecu that will incorperate the auto properly?

In saying time bomb, will it be alright to wind down boost to lowest ( i think 8 psi) and still drive it? thanks again mate this is the info im after

ummm, that is very bad advice...

Seen plenty of cars die from Factory ECUs pinging, too much boost etc.

so a 25 with a t04z running 10psi and hitting "rich and retard" is going to be pinging? pick which side you want, you cant have it retarded and pinging, both instantly killing the motor.

fact: above standard airflow the standard ecu runs richer and richer, usually well into the 10s and sometimes into 9:1 AFR territory as it simply runs the injectors at 100%, impossible to lean out with the standard ecu unless something else is wrong.

fact: above standard airflow the standard ecu runs less and less timing

fact: maxxing the afm (5.1v) results in complete fuel cut

please tell me how this is going to cause grenade like pinging and instant death? i agree entirely that he needs bigger injectors and a better ecu, but until then turning the boost down will be sufficient

so a 25 with a t04z running 10psi and hitting "rich and retard" is going to be pinging? pick which side you want, you cant have it retarded and pinging, both instantly killing the motor.

fact: above standard airflow the standard ecu runs richer and richer, usually well into the 10s and sometimes into 9:1 AFR territory as it simply runs the injectors at 100%, impossible to lean out with the standard ecu unless something else is wrong.

fact: above standard airflow the standard ecu runs less and less timing

fact: maxxing the afm (5.1v) results in complete fuel cut

please tell me how this is going to cause grenade like pinging and instant death? i agree entirely that he needs bigger injectors and a better ecu, but until then turning the boost down will be sufficient

Cheers mate, ill pull the boost right down, so it is safe still? id hate to damage anything. i take from what you said as i cant really hurt it if it does do R&R? it is running quite rich i might add, i always thought if your not detonating, and running ruch, damage is near impossible

not sure what you mean by that but the whole more air at same boost thing is because of temperature. the bigger turbo makes the same boost much more efficiently and doesnt heat the air as much, so same pressure but different temperatures, hence different masses of air

Edited by JonnoHR31
  • Like 1

so a 25 with a t04z running 10psi and hitting "rich and retard" is going to be pinging? pick which side you want, you cant have it retarded and pinging, both instantly killing the motor.

fact: above standard airflow the standard ecu runs richer and richer, usually well into the 10s and sometimes into 9:1 AFR territory as it simply runs the injectors at 100%, impossible to lean out with the standard ecu unless something else is wrong.

fact: above standard airflow the standard ecu runs less and less timing

fact: maxxing the afm (5.1v) results in complete fuel cut

please tell me how this is going to cause grenade like pinging and instant death? i agree entirely that he needs bigger injectors and a better ecu, but until then turning the boost down will be sufficient

this is all correct but incorrect at the same time.

1. Once the injectors hit 100%, what happens? Does extra fuel magically appear the keep making it rich? Nope, it leans. In a very bad way.

2. Does the ECU just keep pulling timing until the timing is zero, or even a negative? How does the ECU know when to pull timing? Does it just magically guess, or it waits for initial detonation then pulls? Here is a fact, the ECU will only pull about 6 degrees max. Not enough for some idiot with a T04Z trying to run stupid amounts of boost.

3. I haven't experienced the "complete fuel cut"

It is still very much possible to put a big turbo on a standard ECU fitted car and blow it up. You're wrong if you think it is impossible. Seen it about 10 times personally, with a standard turbo.

  • Like 2

this is all correct but incorrect at the same time.

1. Once the injectors hit 100%, what happens? Does extra fuel magically appear the keep making it rich? Nope, it leans. In a very bad way.

2. Does the ECU just keep pulling timing until the timing is zero, or even a negative? How does the ECU know when to pull timing? Does it just magically guess, or it waits for initial detonation then pulls? Here is a fact, the ECU will only pull about 6 degrees max. Not enough for some idiot with a T04Z trying to run stupid amounts of boost.

3. I haven't experienced the "complete fuel cut"

1. afm maxxes well before you have enough airflow for 12:1 AFR's with the injectors at 100%

2. so 6 degrees from an already conservative map designed for the standard turbo and much more heat isnt enough? i'd agree if hes filling the tank with heptane. 10-11psi is stupid amounts of boost?

Seen it about 10 times personally, with a standard turbo.

and that there is exactly why its irrelevant in this case. standard turbos create a lot more heat at these boost levels and make detonation a hell of a lot easier, virtually impossible (unless something else is wrong, which would make that the cause and not the ecu like you say) to get knock with a t04z running ~10psi with the standard ecu's knock maps (which it will be using if there is even a trace of knock).

oh and for what it is worth, I have been tuning cars since 2004. I know ECUs, fuel, injectors, boost, flow, etc.

for what its worth what hes experiencing is the exact same "rich and retard" that everyone else experiences with standard turbos at 12+psi and is widely regarded as perfectly safe and just annoying.

  • Like 1

but you've been saying that you cannot kill a motor with the stock ECU, and that is absolutely rubbish.

Now you're saying other stuff, and getting into detail to try and cover your tracks?

The answer is this: You are wrong. You can kill an engine with a stock ECU and ANY turbo.

what is a good map ecu that will incorperate the auto properly?

Vipec or Power FC.

From my understanding & reading threads here, no stand alone ECU works perfect with the R33 Auto transmission, something to do with the fact that the Stock ecu will back off timing when the auto changes gears to smooth out the changes but no stand alone ECU does this thus you will get very harsh gear changes if you remove the stock ECU.

With the auto R34s if you remove the stock ECU the auto gear box will be stuck in 3rd (from what I have read).

i blew my motor on the stock ecu. my boost spiked to 16psi at WSID.

The Mafia hasn't said a word wrong IMO.

for example, you're comparing 10psi from a turbo that is sized like this (o) compared to a turbo sized like this (O) (my examples suck, i know). the air will travel at the same velocity, but the amount of air passing will be far greater on the bigger turbo because its BIGGER, bigger turbine, bigger housing bigger everything. it will create the same boost but more air is traveling. its pure logic mate.

my 3yr old nephew was checking out my turbo i had sitting on the floor. after asking me a few questions he said "you should get a bigger one to push more air" he said that while his mouth was on the compressor wheel trying to blow air into it at the same time. in comparison, he is a fucking mechanical genius compared to you.

  • Like 7

From my understanding & reading threads here, no stand alone ECU works perfect with the R33 Auto transmission, something to do with the fact that the Stock ecu will back off timing when the auto changes gears to smooth out the changes but no stand alone ECU does this thus you will get very harsh gear changes if you remove the stock ECU.

With the auto R34s if you remove the stock ECU the auto gear box will be stuck in 3rd (from what I have read).

im running a vipec with an auto r33. it runs perfectly. the r33's auto runs off a separate computer so there are no interferences between the aftermarket ecu and the auto ecu . i am unsure about the r34 though.

  • Like 1

my 3yr old nephew was checking out my turbo i had sitting on the floor. after asking me a few questions he said "you should get a bigger one to push more air" he said that while his mouth was on the compressor wheel trying to blow air into it at the same time. in comparison, he is a fucking mechanical genius compared to you.

Bahahahhahaahhaha!

  • Like 2

but you've been saying that you cannot kill a motor with the stock ECU, and that is absolutely rubbish.

Now you're saying other stuff, and getting into detail to try and cover your tracks?

The answer is this: You are wrong. You can kill an engine with a stock ECU and ANY turbo.

so you honestly believe that this guys motor is a ticking time bomb at 10psi?

your right you can kill an engine with a stock ecu and any turbo, you can kill any engine with any ecu and any turbo, it doesnt automatically mean the ecu is the sole cause of its death, which is my point.

example, go buy a mint condition (like new) r33, bolt a massive turbo on and run whatever boost you like. now dump all the oil and sit on limiter. if the engine dies is it because it had a standard ecu?

  • Like 1
  • Nope 2

not sure what you mean by that but the whole more air at same boost thing is because of temperature. the bigger turbo makes the same boost much more efficiently and doesnt heat the air as much, so same pressure but different temperatures, hence different masses of air

Hi Johnno

Additionally, the change in pressure also comes from the much larger turbine housing outlet which effectively uncorks the engine.

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