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How far can you push the Std Management

Posted: Thu Apr 10, 2008 10:56 am
by rat
S13 std ecu, how far can you go?

Like t28 and setting the boost up to 0.8, injectors think max out here.

Posted: Thu Apr 10, 2008 12:14 pm
by Sokar
Common consensus is 250 - 300hp on the wheels...

Posted: Thu Apr 10, 2008 2:04 pm
by Gary57
That is about the limit for stock pistons aswell. Injectors will max out at about 150RwKw or so.

Posted: Fri Apr 11, 2008 9:54 am
by rat
So my White sx which has a
T28 running at 0.8
Cone Filter
FMIC
63mm
Walbro pump
dicktator management doing 148rwkw

doesnt really need the management?

Posted: Fri Apr 11, 2008 11:28 am
by Gary57
Nope stock management will do.

Posted: Mon Apr 14, 2008 7:46 am
by MyPRodOL
it actually does need it... you running on the limit. if 150wkw is the cut of and you doing 148wkw.... it to much on the limit. Injectors are almost running full duty cycle which is not good, as they get overworked and will eventually brake. if they brake your engine will most probably brake.

Or what if you get a boost spike up to 0.9 or 1 bar, and then the injectors can't supply fuel and the management kicks into boost cut and wham goes your motor...

Do injectors and get a piggyback system... it can only be good... no matter how you look at it.

Posted: Mon Apr 14, 2008 9:02 am
by VoodooMaster
Dumb question (I'm not that technical minded)...... But I was reading this now and trying to figure out what is rwkw & wkw?
I know KW is kilowatts. :?

Posted: Mon Apr 14, 2008 9:57 am
by rat
@voodoo - Rear Wheel Kilo Watts

@MyPRodOL - 0.8 the injectors are running at 80% duty cycle, which if i understand right is the safe limit (correct me if i am wrong). Do think the next step is bigger injectors. What is a piggyback system?

Posted: Mon Apr 14, 2008 2:10 pm
by ChemCool
Something like UNICHIP
Chem 8)

Posted: Mon Apr 14, 2008 2:37 pm
by Speed breeder
Piggyback, so not stand alone, needs original ECU to function or works in harmony (or non harmony) with your existing ecu.

I suppose you have to decide what your future plans are.

I don't think its wise to do too many mods to your car and running original ECU setup, even if you do a chip.

Posted: Mon Apr 14, 2008 8:22 pm
by veecee
lots of people think its unwise to run a chip!!!

but there's lots of theory on all this...

myprodol - its not boost cut, its fuel cut. how will the stock management on a ca18det with a stock ecu cut boost - it doesnt have electronic boost control on it!

and if it cuts fuel the engine wont brake, it will stall though!

Posted: Tue Apr 15, 2008 10:50 am
by MyPRodOL
@ rat - 0.8, on the safe limit exactly... some people, might be happy with that... if its on the limit its working hard, if its working hard there's always chances of it breaking.

Depending on what power you plan to make one day, will determine what kind of ECU setup you need. If you making mild to low power with basic mods, a piggyback system is fine... meaning it sits on the standard ECU and allows you to change values etc, meaning you van tune your car.

These piggybacks can't always support big power and massive mods, so than you go stand alone, this replaces the whole stock ECU with a after-market one.

Th stock ECU from Nissan is actually freakin good, problem is you can't change the values... meaning you can't tune. so piggybacks allow you to that.
Its sometimes known to have smother day to day running etc, but the stand alone can be a bit crusty etc as its not as refined as the stock ECU.


@ VEECEE - I know... there is more than one term for that... its referred to as the dreaded boost cut...

Its the same theory, comes down to the same point... o and it can pop your motor.

What happens is... your stock MAF works in VOLTS, meaning certain air flow will calculate to certain VOLTS. If its small sensor it can't read too much air, thats why you fit a bigger sensor like the Z32 etc.

So now you boost.... more than the sensor can read, and it zero's out. the ECU goes into Fuel cut mode as it can't understand the values given from the MAF and that can cause the motor to run lean... which will cause immediate knock, and this can result in a popped motor. As we all know... bad knock can blow a motor in seconds.

This won't always happen, but it can...


@VoodooMaster - wkw is what you put on the road and fly is what the motor makes.

You loose allot of power from the motor to the wheels through transmission etc.. so wkw is the real makoy.

Posted: Tue Apr 15, 2008 11:41 am
by Speed breeder
just out of interest... I always use the following formula... and there could be a lot of theories behind this one as well... Not looking for an argument

hp x 75% = Kw

flyweel kw x 75% = wheel kw

so strictly speaking flyweel hp x 75% x 75% = wkw

This is not accurate as it does not consider different diff and gearbox or even flywheel setups, but is a quick and nasty...

I haven't been too far off when at dyno days and there were bets flying about what the kw's would be on the cars there.

You wait for a car to use as a base to calibrate the specific dyno and to also take cognisense of the conditions on the day... for example a golf or an opel or something...

You will be able to estimate what other standard cars would do on this dyno

So if you want to see if your modified 200sx has improved from standard.
Use a standard car as a base

1600 golf = 70 something flywheel kw per manufacturer = 52.5wkw
How close was dyno...
200sx manufacturer flywheel kw = 125 or something, so 93.75kw
If the dyno was close for the golf it should be close for your car as well.

Important to note it has to be the same conditions (Same day and time) and same dyno.

I am not taking into consideration the settings that may be changed on the dyno during runs.

And I am sure someone is going to add their view on this...


There is not a lot of tech behind my thinking... but again I don't think I will be too far off.

Posted: Tue Apr 15, 2008 11:56 am
by MyPRodOL
@ speed breeder -

thing is... no dyno can actually read fly kw... it just can't, its actually worked out from wheel kw.

The dyno's we know reads wheels and the calculates fly from there.

Only engine dyno meters can measure kw at the fly...

I understand your method of thinking etc, nothing wrong with what you trying to achieve...

and what about 4wd cars that loose like huge amounts to the wheels, i mean huge!

This is were the big issue comes in with regards to the dyno's and their figures etc. is what method of calculation was used to calculate the fly kw...

Posted: Tue Apr 15, 2008 12:09 pm
by Speed breeder
@ myprodol...did i say anywhere that a dyno reads Flywheel kw?
I was actually expecting a more technical comeback...
and why would anyone be interested in flywheel kw's and working back to this?