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The PFC ebc is good (varied duty cycle throughout the rpm to hold the target boost pressure), UNLESS your making silly amounts of power..

The use of an AVCR where you can have different boost levels in different gears is usefull to prevent wheel spin in the lower gears.

Edited by Cubes
umm.. isnt it the other way around ?

I would have to agree, just becuse the car is tuned for say 18psi, doesnt mean its not tuned for a lower boost setting. If its tuned for 18psi then it has to be tuned for everythign below it as well. ie 1-17psi

Mick

As you approach the higher load points the resolution becomes less.... As a result running a lower boost level that still uses the same load point will cause the afrs to be richer.

For example.. My Rb30DET running the vg30det turbo at 9-10psi uses the same load point as when its at 13psi.

Which is one benifit of the more expensive ecu's such as the Motec's and Autotronics.. More load points = finer tuning. :)

Edited by Cubes

That would throw the tune out even furthur.

Not being picky about numbers the higher the pressure the more heated the air is, resulting in less dense air + closer to the edge of detonation. Less ign. will have to be run on the higher boost resulting in less than optimal ign timing for the lower boost levels.

Edited by Cubes

also remembering boost is only a pressure rating, running 12psi and 24psi certainly doesnt mean the 24psi tune will flow double the amount of air. the powerfc dedides load points on airflow meter signal. so at 3400rpm on 12psi or 19psi it will still be reading the same load point as airflow meter says 3400mv (despite more pressure) as pressure and volume are two different things

i run a power fc in my s14 and also a greddy profec b boost controller

why ive done this is i dont know how to tune a computer so why have a hand controller when i bought my computer for less and i have a straight boost controller

my old school greddy profec b is the best controller around in my opinion. it is as basic as anything and i regularly have it on low boost rather than high boost. i think the whole throttle control by the right foot in theory is a great idea however it doesnt always work

with my car i like to run it on low boost knowing that i can nail it without it spinning my tyres to pieces

personally i think running a boost controller through a power fc controller is more effort than its worth

having used a stand alone boost controller and the powerfc one i think either is fine. set the highest safe boost you can run and use your foot to control the pedal. why woud u want low and hi boost? what on earth for? if you wanna go fast, floor it, if not soft pedal or medium and youll accelerate as quick as you want. if you have wheelspin when on boost then you need to sort out your tyre/suspension setup.

using different boost settings to control traction is hardly a good argument. you may as well put in regular unleaded instead of premium to limit wheelspin then

and your arguement over why have a hand controller? i dont get it.

the hand controller is a multipurpose unit, it can give you information, allow you to make informed decisions and adjust settings on the fly. if you dont know how to use it, learn.

Paul,

Your analogy is very poor. Using a boost controller to control traction in a high power car IS extremely usefull. Especially in second gear where you don't need 300+rwkw. The other option is to step up a turbine a/r size. Given the smaller a/r provides enough flow for the target power I would much rather have the option of using an EBC to control boost level in different gears. ESPECIALLY with a RB30DET that has such an insane hitting mid range traction is an issue.

A good condition R32/R33/R34 shouldn't have issues with wheel spin until over 250rwkw. Unless your a fag and running razor blades on stock black rims. ;)

Mine had wheelspin issues at 176rwkw..

Stuffed subframe bushes + a loose VLSD + the 3ltr doesn't help.

The 2.5ltrs come on and ramp up to peak power so much smoother than the 3ltrs. Comparing dyno sheets at the last dyno day illustrates this.

Edited by Cubes

whilst it may be poor i dont see (myself anyway) why you would want to run different boost settings. i would prefer to have the car setup for the highest safe pressure and have the handling sorted out correctly so that it will handle the power correctly. instead of using low/hi boost and gear judge settings

well, i filled up with bp fuel today that wasnt optimax (couldnt be bothered waiting for an optimax pump)

so, i just choose low boost option on pwfc and not worry about it until ived used up this tank of petrol

much easier than worrying about how much throttle to use

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