RB20DET internal wastegate spring rate

[-Justin-]

I was asking about a internal boost controller

http://www.trademe.co.nz/a.aspx?id=278449460

as you can see the guy said i need to find my spring rate..????

had a look in the manual as i have a copy of one and theirs nothing about the spring rate just a section testing the internal wastegate



and another section testing the factory BOV. Any ideas on how i can find my "spring Rate" ?

[FLAWLES]

??

just get the boost controller set it to 10psi and bam you will be sweet

only need to worry about actuator spring rates if your running an aftermarket actuator and or an external wastegate............and or a huge f'ing chur-bro

most internal waste gates are good for about 1bar ( 14.5psi ) or there abouts before you have to get and aftermarket item and or go external

asuming you are running the factory rb25det turbo?

i think thats what you are asking

[-Justin-]

I forgot to mention which is kinda the main topic im looking to bring my boost DOWN not up and every f**kn product is made to increase not decrease boost. This is for a rb20DE+T setup tuned for a safe 7psi

[FLAWLES]

a boost controller will have ( should have ) a setting of 0% zero being the factory setting and from there it goes up in a % ( i know the hks evc-s and blitz sbc id-IIs do )

failing that get a boost tap and wined it closed as i know for a fact that you can bring those down to around 5psi with a smidgin of boost creep

[Akane]

Justin you gotta friggin' listen to advice sometimes.

I've told you already, you can't bring down boost with a boost controller, you can only bring it up.

And if you do the whole arm extension BS you'll just delay the onset of boost (If your exhaust energy produced exceeds the amount of boost is achived with the preset arm setting).

You either do 1 of the following.

1) get a wastegate with an internal spring rate of 5psi

2) like what I said before, have another pull spring working the opposite direction to offset the internal diapharm's spring's spring rate.

FF friggin S.
If you don't wanna listen to advice, then don't ask for one in the first place.
Go back to SDU or something, maybe they can wave a magic wand around your actuator.

[FLAWLES]

you want to explane to me why a boost controller " cant " bring down the boost level?

[bbq1988]

because the base setting depends on actuator strength, and controllers work by bleeding off the boost via a solenoid between the boost feed and actuator (Most Cases)

[FLAWLES]

basicly what i said above,

the factory actuator will be fine,
if you want the controller to run at 7psi dial it in at 7psi, or what ever the factory setting is/was
i had the blitz sbc set at 7psi and it was fine with the factory actuator, intill i started ti get into the 1bar zone

to say a boost contoler can only bring boost up and not down is b/s

[Akane]

to say a boost contoler can only bring boost up and not down is b/s

It's not BS, think how a boost controller works.

It "fools" the actuator by feeding it less pressure, so it sees less pressure and opens later.

You can't make it open earlier than what it is set from factory.

You can only bleed pressure off, you can't add what's not there.

basically what bbq1998 has said.

I have read your post over and over again, to me at least, what you have said is regardless of the actuator spring rate, you can bring boost up and down (even past what the actuator is set from factory) at your own free will?

That itself, looks like BS, smells like BS, I think it's BS.

I forgot to mention which is kinda the main topic im looking to bring my boost DOWN not up and every f**kn product is made to increase not decrease boost. This is for a rb20DE+T setup tuned for a safe 7psi

That's because you FRIGGING CAN'T

Gimme a hammer someone, so I can hammer that fact into your head

[FLAWLES]

Justin you gotta friggin' listen to advice sometimes.

I've told you already, you can't bring down boost with a boost controller, you can only bring it up.

And if you do the whole arm extension BS you'll just delay the onset of boost (If your exhaust energy produced exceeds the amount of boost is achived with the preset arm setting).

You either do 1 of the following.

1) get a wastegate with an internal spring rate of 5psi

2) like what I said before, have another pull spring working the opposite direction to offset the internal diapharm's spring's spring rate.

FF friggin S.
If you don't wanna listen to advice, then don't ask for one in the first place.
Go back to SDU or something, maybe they can wave a magic wand around your actuator.

lets stop and rewind here for a minute aye

one i dont know what this guy is plaining to do you obvisly do,
from what i have read he is doing a plus T conversion, sweet good on him
and wanting to run factory boost setting? correct? which is what on a rb turbo? 7 to 8psi?

you have clarely stated that you cant bring boost down with a controller? have you not.........says it above, which its self is alie,

That itself, looks like BS, smells like BS, I think it's BS.

you summed it up nicely i thought

why have a controller that you can olny up the boost and not bring it down to regulate boost to your desired level
yes it fools the actuator into
A) holding vacum
b) releasing vacum

you are right in saying you cant bring boost down further than what the factory actuator is set at, i should have said that but failed

but is that what he is wanting to do? bring it lower than 7psi? not from what i have read

so lets start again

this chap wants to run a rb20de + t @ 7psi using a boost controller of sorts correct? yes no?

so

factory actuator @ 7psi + controler = fine
factory actuator @ 7psi + boost tap = fine
factory actuator @ 7psi + factory set up = fine

why you want to find a actuator that runs with 5psi i dont know

[sergei]

basicly what i said above,

the factory actuator will be fine,
if you want the controller to run at 7psi dial it in at 7psi, or what ever the factory setting is/was
i had the blitz sbc set at 7psi and it was fine with the factory actuator, intill i started ti get into the 1bar zone

to say a boost contoler can only bring boost up and not down is b/s

I am sorry but boost controller can only bring boost down to whatever is the wastegate rated.
It cannot magically supply pressure above of the pressure that turbo making, unless you have some sort of compressor in there.

In simple terms, if waste gate is opening at 8 psi at diaphragm there is nothing you can do with boost controller to lower that figure (as you need to supply 8psi, but your reference has only 5 psi so it will stay closed until reference gets to 8psi).

[bbq1988]

I forgot to mention which is kinda the main topic im looking to bring my boost DOWN not up and every f**kn product is made to increase not decrease boost. This is for a rb20DE+T setup tuned for a safe 7psi

Just run it on what the factory gate is mate, 8psi or so

[mjrstar]

looks like the factory w/g will give you around 11-12 psi .8kg/cm no less (from the info you provided)

You can then work out spring force by using F=P X A blah blah blah but not a lot of point in this case.

As mentioned above you cannot lower the boost level below the base pressure of the wastegate spring with any sort of 'boost controller'.

I have heard of the T25 turbos running a 7psi actuator possibly something from a 200sx or early 300z but some more searching would help on the internets may be able to confirm that.

You may still need to adapt the arm and mounts to make it all work.

[Akane]

one i dont know what this guy is plaining to do you obvisly do,

He wants to run 5psi on an actuator that's rated for 7psi. Because he has some magic chip that he's gonna put in but it is only mapped to 5psi only.

And he's getting his panties all in a knot over it

He asked for advice, we gave him some, some good, some not so great.

Then he just ignores those advice and opens up a new thread and asks for more advice.

I've given him advice that'll cost him $2 and gets what he wants (providing he has the correct mounting somewhere to hook the ends of the springs onto).

But no, he rather spends $215 on some electronic boost controller and trying to "dial the boost down au!"

I don't know, it's like I'm trying to help, but getting denied.

It's obvious that he's doing it "on the cheap", shxt, I don't know what can be cheaper than a pull spring working against the internal actuator spring, it's cheap, reversable, reach the desired boost faster without overboosting, and somewhat adjustable (more springs au!).

And maybe one day when he can afford to go higher boost, just turn the springs in the opposite direction, boost controller au! Helps spool somewhat and mad skids, au! That itself, is more epic than the Chinese recycling used oil.

[-Justin-]

wow..............A lot of replys

Akane i did take your advice into consideration you have to understand i have about 50 different people teling me to do a million different things and on most occasions these ideas or suggestions do contridict each other. In this thread i was mainly after finding out the "spring tension" for a rb20det turbo so i could see if this boost controller would work. Obviously the guy on trademe is al shit suggesting that i can lower the boost below the factory internal wastegate setting which is around 11 psi on a rb20det turbo as you have gladly pointed out, which is good to know as i said before only products i can find increase boost and i thought this boost controler was my magical answer but once again it failed. The spring option does sound good but i have never puled apart a wastegate let alone started messing around with the springs, If your stil keen or can be bothered on telling me in detail how i would go about this spring setup im more than keen to listen as i dont really know what im doing and if i fuk up the boost POP goes my engine, i wana do this properly hence the spamming of boost posts, sorry if iv pissed anyone off

[Akane]

It doesn't involved on pulling everything apart.

All you do is have a pull spring. You can get it at any hardware store, they're like... $2

They look like this



You hook one end to somewhere along the arm, and the other end to a point, any point that won't crumble.

Pull it so it HELPS the wastegate open easier.

I have this setup, on one of my cars, except i'm helping the wastegate CLOSE for longer.

It cost me.... a pull spring, a hose clamp.... and some monkeying around under the bonnet for an hour.

I took apart NOTHING.

boost went up from 0.80 kg/cm^2 to 0.92 kg/cm^2

I'd tighten the hose clamp to make the pull spring pull harder, and I'll get a teeeeeeeeny weeeeeeeeeny bit more boost.

Simple. Yet so effective.

[iOnic]

Just do it properly and tune the engine to run on the stock wastegate boost pressure.

to say a boost contoler can only bring boost up and not down is b/s

I lol'd. Learn how these things work before you try giving people advice.

[sergei]

Is this the continuation thread of running RB20DE with a turbo? a question might arise - why not run stock ECU/map sensor off RB20DET?

Also do you realise that 2psi difference is almost nothing? To put in perspective 2psi is ~0.14 Bar - this sort of pressure difference you get with changing weather, cheaper boost gauges will not read that fine pressure accurately anyway. If you blow on the pie because it is thermonuclear, this is the pressure you will be blowing with.

If your engine/ECU cannot handle 7psi, it will not handle 5psi either.

[shihad]

although i havent read the whole thread or the other thread if it helps the reason he wants to run 5psi is because he will be running a chip that is setup for 5psi.how about asking the guy selling the chips if hes got one for stock rb20 boost? surely the compression would still be fine with this.

[tsoob]

Justin:-

Punctuation please!