Maximum Boost on standard ECU?

[VH 1UZ-FE]

Hi
What is the maximum boost that the 1UZ-FE standard ECU can handle? And does anyone recommend a certain brand/type of supercharger for this? The engine is a crown royal saloon 1991 model.
Thanks.

 

[jordys ski boat]

it depends on how much money you have a centrifical type is about 2500 to 3000$ just for the supercharger and you can pick up an eaton for around 1000$ or cheaper the standed ecu can handle 5 psi im not sure about anymore but value for money you cant go past an eaton you can do the hole job for about 2000$

 

[VH 1UZ-FE]

my mate has some small superchargers (side mounts) and he picked them up for $300-$400 each. Is there any out there for this kind of price that are good and will deliver about 5psi? I am looking at spending as little as possible to get around the 5 psi mark.

What happens after 5 psi to the ECU? will it stop the engine? or just run like ****?

 

[Zuffen]

VH,

You have posed a question that doesn't seem to have any takers.

I too would like to know what happens after 5lb?

Is there a problem with:
1. Detonation.
2. Fuel supply.
3. ECU's inability to understand the increase air flow.

If the answer is point 1. Intercooling could be the answer.

If it is point2. larger injectors, increased fuel pressure is the answer.

If point 3. We have a problem.

Does anyone have the answers on this?

 

[Lextreme II]

The stock ECU is good until u upgrade to larger injectors.

 

[Dreamkiller]

I thought the ECU is good to 8psi, according to lextremes twin turbo article?

 

[Lextreme II]

Yes,

Stock injectors can handle 8 psi max. Therefore if you upgrade to larger injectors you will need to upgrade ECU. I would say over 350 cc/min. So 8 psi still valid.

 

[Lambo]

ecu and airflow

HI Guys, In reply to Zuffens problem no 3
A few years ago i dropped a 2.6 turbo into my 82 Mitsi starion 2L all i did was, increase the size of the bypass port in the airflow meter, so the same amount of air goes through the sensor, the extra air goes around the sensor ,then added a variable resister to the computers water temp sensor, that retarded the spark, increased the fuel flow,as the ecu always throught that the engine was cold, that allowed me to run 10-12 boost and 6 years later still goes like stink gives lots of moderns a fright, maybe its possiable to do the same on the 1uz

Best Regards
lambo

 

[ozvenom]

boostn

The only real limitation of the standard ecu is the air flow meter its not the amount of boost it controls its amount of air it flows . They work on a 0-5 volt signal and once it reaches max output the ecu has no idea what to do next except throw up a fault code and go into limp mode . The amount of air it reads is also affected by air temp as this affects the air density.

Detonation is not a problem as the ecu has knock sensors in each bank and retards the time off when it detects detonation.

The easy way to get more fuel into the motor is by using a fmu (fuel mangement unit) these increase fuel presure above what the standard regulator does in varying ratios ie 4:1 6:1 8:1 which means for every psi of boost you get it increases the fuel pressure by the ratio ie 4:1 5psi is 20 psi of fuel pressure which is approx 15 % more fuel flow. the standard injectors will flow about 1% more flow for ever psi extra over manifold pressure.

I hope this helps regards oz

 

[Lextreme II]

Oz,

Well said. I think most people get carry away with piggyback and stand alone computer with low boost applications (Less than 8 psi) FMU is the K.I.S.S. Method. Keep It Simple Simple method.

Its almost no benefit using piggyback or standalone less than 8 psi. Dont waste your money and time. FMU can make your headaches goes away.

Here is my recommendation:
1. Less then 8 psi: FMU with possible fuel pump upgrade
2. 8-15 psi: Piggy back-350-390 cc/min injectors, fuel pump upgrade
3. 15-18 psi: high function piggyback with timing control-400-500 cc/min injectors with fuel pump upgrade
4. Beyond 20 psi would be stand alone arena.

 

[LEXUSV8NZ]

Speaking of air flow metres...
Would this be the same case as in Nissan engines when they replace RB26DETT AFM's with VG30DETT 80mm units? as the VG units flow better and offer higher resolution, is this the same problem that the 1uz would experience?

Logan

 

[Zuffen]

From what I can see the T/B can't flow enough air so the ECU does not know to supply enough fuel.

What will happen if you used a larger T/B and matched injectors?

My thoughts are if I use a Ford Lightning T/B, Blower, Intercooler and the correct Injectors the ECU may work. I know there will most likly be problems with the injectors resistance but can this work.

I will probably run Autronic when I fit my supercharger, but am curious to know if this would work.

Any experts out there with an opinion as to why it should/should not work?

 

[1UZFE Matt]

I understand there is two different cc ratings for standard injectors on 1UZ's.
I think I have the lower cc ones on my 1UZ as it is an 1989 Crown. Will my engine take 8 psi with the stock management and increased fuel pressure?
Regards
Matt.

 

[Lextreme II]

I think Crown is 220 cc/min and Celsior is 251 cc/mm. I would not recommend more than 6 psi on the Crown.

There are few upgrades u can do. They are all plug and play upgrade injectors

1. Celsior injectors 251 cc good for 8 psi
2. 4-AGZE i heard its 269 cc or something like that.
3. 3SGE is -295 cc
4. Surpa MKIII 7MGE is 295 Yellow,
5. Supra MKIII 7MGE is 315 cc Light Green

 

[hungryforinfo]

Great thread this one.

I have the 251cc injectors, and want to run 8psi, but was thinking of using a set of 315cc injectors instead of a FMU.

Anyone think this could be a cheaper alternative?

 

[hungryforinfo]

8lbs on stock injectors, or 8lbs on 315cc injectors?

 

[hungryforinfo]

Sounds like it would work okay from what I read here, so I am going to give it a go?

 

[hungryforinfo]

8 psi it will be then.

Thanks again.

 

[V8hilux]

Mine is running 14psi with ridiculous intake temps, on a stock un opened motor. They are tough cookies!

 

[Thermactor]

Mine is running 14psi with ridiculous intake temps, on a stock un opened motor. They are tough cookies!

wow! any more details?