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well the way I see it..

hks actuator is set to 1bar right?

so in order for it to be a smooth transition, it probably cracks open a little at a lower boost pressure than that.

for arguements sake, lets say it starts to open at 8 psi..

so you have all gasses going through exhaust wheel until 8psi, where it bleeds some out of the wastegate flap..

this opens more and more until it is open enough to flow only 14psi worth to the engine.

if you had a boost controller of some sort, it would stay shut for longer..

not all can do it but to name a few..

JAY CAR boost controller.

SK has posted on here about how you can pretty much keep the wastegate completely shut till the set limit at which time it will fly open.

this will give you much more kick in the back than just actuator control.

autospeed DIY boost controller

Once again good old SK has explained how good a device it is.

for like $100 of parts, you can build your own. it has 2 knobs where one controlls the boost pressure you want to run, and the other controlls at WHAT boost pressure the wastegate starts to open before fully opening at set boost level.

both the above have been posted on SAU.. search and you'll find it.

but then I think to myself... "the man has an HKS turbo on his car, he has dosh to buy jap Electronic boost controller"

at this thought, there is a world of options.

Most EBC's have a "GAIN" or "RAMP" funciton.. pretty much a fancy word to describe how hard the boost comes on, which is due to keeping the wastegate shut for longer.

GTST

Your explaination of a wastegate operation is not quite right.

Lets say your wastegate is fully open at 10psi.

When the wastegate is shown 5psi, the wastegate is half open. This is called wastegate creep.

With the Autospeed, Jarcar and other boost controllers, you are stopping any pressure getting to the wastegate hence bringing on boost earlier.

GTST

Your explaination of a wastegate operation is not quite right.

Lets say your wastegate is fully open at 10psi.

When the wastegate is shown 5psi, the wastegate is half open. This is called wastegate creep.

With the Autospeed, Jarcar and other boost controllers, you are stopping any pressure getting to the wastegate hence bringing on boost earlier.

I did say my example was for arguements sake..

fact is that his hks actuator which allows him to see 14.5 psi, is actually opening before that..

and a boost controller which allows control of "RAMP/GAIN" what ever you want to call it, will make the boost come on stronger..

even if he doesn't change the final psi figure.

also, if you've ever seen a dyno graph with 2 different boost settings (lets say 10 psi and 15 psi), the 15psi run will get to 10psi faster than the 10 psi setting. as you said, due to the fact that the wastegate does not open as early.

so as someonelse in this thread already said.. WIND UP THE BOOST

;)

i see fellas...

more boost is always the best remedy.

apparently i need the bigger injectors cos i dont want to be running insane pressure thru the fuel rail.

im gonna have a go at fabricating my own split/screamer pipe aswell. this might have an effect on lag as i might be getting some turbulence with just a 3 inch down pipe coming off the turbo...

ill get a ebc and wind the boost up to 17-18psi and hope that keeps me happy for 5 mins

the mines idea is not really an option, would cost a fortune.

I just have a standard turbo with a Blitz SBC I-DIII- electronic boost controller.

You can notice a difference even when you run stock boost(8PSI) it comes on so much earlier and sharper.

I usually run 10-12 psi depending on the mood. Having the EBC makes it really easy to switch between setting.

The EBC i have is extreamly accurate, as in +- 0.1 psi 90% of the time the other 10% would be +-0.2 psi (at 12 psi on a 8psi actuator)

I think even if you were to run the same boost with a good EBC you will be happy with the gains. And when the novelty wears off you have the facilities to turn it up.

That makes so much more sence... i always wondered why boost seemed to come on earlier and stronger on 1bar than on 0.8bar!

The wastegate opens later because of boost levels bein higher blah blah and you get more boost earlier. This is awsome because now i know i wasnt just thinking it, i knew it came on earlier on high boost!

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