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I'm interested to hear peoples first-hand experiences with the "HKS" copy external wastegates that are available online.
Before you start telling me "I told you so" or "you get what you pay for", i'm purely interested in finding out who has one, and what you think of it in operation. In particular, I am finding it difficult to avoid inconsistent boost levels when using either a conventional bleeder or norgren valve style controller to increase boost. At the rated spring pressure of 8psi the boost is perfectly stable through the rev range, however once a boost controller is fitted, I don't seem to be able to avoid having boost start out high for the 1000rpm or so, then settling down to 3psi lower than that. For example, boost will come on at 17psi from 3500 to 4500rpm, then settle down to 14psi from there to redline.
Has anyone else found this, or have any ideas what could be causing it?
AE71 Corolla 2 door window van - retired / JZA70 Supra - VVTi converted - sold
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Last edited by celicapain; 30-05-2007 at 11:08 PM. Reason: .............
GA23(never finished-now with cracked block ) JZX83 (Tyre eater) 3sgte AE86. by now i should know better.
sounds like good ol boost creep to me!
At a guess id say its prob due to one of two things.
1. The cheap wastegate spring doesnt like working under compression where its spring tension is unstable.
2. Size and design of gate.
The spike in you case is caused by the exhaust gas pressure having troubble initially lifting the valve from its seat. Once the valve is off its seat the gate can go about controlling the boost.
I would first look at the size of the vac line you are running to the gate. You will need a 5-6mm line to supply as much air as possible to the gates dighpram to get the valve to initially lift from its seat.
So make sure there is no restrictions in the supply line and that the fitting is of equal size.( not 5mm line on a 3mm fitting ! This is just a waste of time !!!)
300+rwkw 4agte http://www.toymods.org.au/forums/for...wkw-4agte.html
Ive got one, only problem I had was the 22psi spring it came with
So i bought a hks spring for it and its worked great
2 years and counting
KE38 - 2TG
MS65 - 1UZ
I had no dramas with the 9psi spring in the one I had in my soarer, bled it off to 19psi and it worked fine
Project Soarer II - Sold
Evo 5 - The silver fruitbox
"I'm the man who has the ball. I'm the man who can throw it faster than f**k. So that is why i am better than everyone in the world. Kiss my ass and suck my dick... everyone."
The vacuum line and fittings are all 6mm, and are as short as possible.
Mine also came with a 24psi spring (advertised 11psi of course ) but Justen managed to source 8psi replacement springs, which it holds perfectly, its only when I start to adjust boost that the problem arises.
The gate has a 40mm diameter valve
AE71 Corolla 2 door window van - retired / JZA70 Supra - VVTi converted - sold
From what I read here, his is doing the same, but when he tries to run a boost controller to run boost above spring pressure, it causes problems.Originally Posted by MR 1JZ
I had the same on my car ( although I was running an internal gate)
Boost spike can be caused by many things,
but the two I found made the main difference were,
a crap boost controller
and
The hoses from the pressure source to the controller to the wastegate are too long or too large.
I changed to a good Electronic controller ( must run closed loop, not like an Gizzmo IBC)
and relocted the valves etc so the hoses were quite short,
and 90% of the spike was gone.
It sounds to me liek you are running a bleed tap, which will quite often give the symptoms you describe.
Why not get a higher PSI spring so you just run straight spring pressure?
- KE70 Corolla Dx -
- 500hp+ 7AGTE 20V turbo -
- MRS/Hayabusa turbo **sold**
- TA63 3TGTE project in the build -
I would recommend a good electornic boost controller too, that can vary the amount of boost bled off from the system so as to minimise spike and to bring boost on a little quicker (the old hyperboost thing of blocking the line until you get close to the boost you want).
I see a couple of ways of doing this:
- closed loop EBC
- fully programmable EBC (jaycar)
- getting the HKS spring like EMP did
...... butt scratcher?!
ive got a ebc and a cheapy wastegate, works fine so far. minimal spiking
1st gen profecB ftw. these things are the shit.
From what I have read abouit them,Originally Posted by The Real Roadrunner
they are still only an open loop Duty cycle controlled unit.
If your car has a boost spike problem It wont fix it.
You need one where you set boost, not set duty cycle.
- KE70 Corolla Dx -
- 500hp+ 7AGTE 20V turbo -
- MRS/Hayabusa turbo **sold**
- TA63 3TGTE project in the build -
A controller like for example blitz sbc id3 can do this, but there is a side effect in you can't set gain, which means the rate boost comes on is up to the controller. In my case I wanted 23psi, wastegate is 13psi, boost controller would not give me full boost on a stall up on the converter, so have to run manual duty cycle based boost control. Comes on heaps faster, but get a little spike, but who cares, spike only occurs for a fraction of a second.
Toyota Corolla Conquest 2003 black manual 1ZZ-FE - Daily
Toyota Soarer GT-TL 1991 white auto 1JZ-GTE - [email protected] 1.587 60'
My JZZ30 SOARER
I'd point the finger at the bleed too Phil...was the bleed valve 'gated' as most are these days? and i suspect the Norgen is just taking too long to respond?
Lily Simpson 6.7.2010
R.I.P.
Nup, not gated, just the norgren pressure limiting valve on its own. I too feel that it is probably very good at holding the set pressure, but not so good at getting to it without spiking past first for a bit
At the moment i'm now simply running a t-peice with a 2.5mm bleed to get a reasonably consistent 13psi. Still spikes a little though, might just have to deal with it for now.
AE71 Corolla 2 door window van - retired / JZA70 Supra - VVTi converted - sold
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