sk8world

iTrader: (5)

I have not had a solid turbo system since my last set up. I swapped to my current A-spec long runner gt4094r kit with 4 inch exhaust 2 years ago. I originally ran a Tial 44 gate and have had boost creep from day one. When Ray came to tune my car last year we never got to finish the pump gas tune as the creep was too bad. Just on spring alone with (10psi spring) it would creep to 12-13 by 6500rpm and still be going up. Ray turned the controller on (old profec B) and ran it to 7k and was around 16psi and the settings were as low as they would go. You could here the gate open around 10psi but the boost pattern matched the rpm pattern. So we stopped and put the Q16 in and ran it with everything the same and saw 18-19psi at 8k. Once we turned the boost up it started to hold some what solid but was not dead on. The max boost we got that day was 24psi with controller wide open.
So a few months later I swapped to a synapse 50mm gate and still have the same issue of unstable boost down low (creep). I just take it easy on the streets and try not to get too crazy. When I go to the track I just turn the high setting on wide open and it runs pretty damn consistant 24psi.

End of last season I wanted to try more boost so I put in a bigger spring in gate and still saw the same 24psi?

The synpase gate is hooked up by the following:

Port A and C, A going to a T, T going to Comp housing and to inlet on boost controller box. The other port B going to boost controller out. (going off the top of my head and sick today so sorry if this isnt perfectly clear).

I am thinking my creep could be from the turbo hitting so hard so quick and location of the wastegate?

thewird

iTrader: (8)

The reason, you couldn't go over 24 PSi on your Tial was because your spring was only a 10 pound spring. You generally can only take boost up to around double the wastegate spring.

A possible reason your boost creeping at low boost is because your manifold does not have priority for the wastegate or maybe the size of the wastegate piping isn't big enough for the wastegates. Hard to say without seeing it. Boost creep generally happens at lower boost since that is when the wastegate is used more. The more you up the boost, the less you need the wastegate for.

Your supposed to hook up the boost controller like this... A & B are T'd together for the boost controller.



Also, did you cap the M4 hole at the top of the Synapse gate?

This one has also been mentioned but I always thought the top one was correct way of doing it.



thewird

sk8world

iTrader: (5)

I agree 100% on the Tial. I only swapped to try and solve the creep issue. I will go back and look at the Synapse forum. I think there was a thread showing to install it the way I did. I did cap the top.

thewird

iTrader: (8)

What were the settings on the boost controller? Gain should be set to 5%, boost becomes unstable when you start to increase that.

thewird

sk8world

iTrader: (5)

Mine has balance-low boost-high boost. My balance is set about 1/4 of a turn. Dip switches on back are set for over boosting issue,

thewird

iTrader: (8)

Oh, your using the OLD profec. I only ever used one of those and it seemed to work the same as the new one. Set balance/gain to 0 and tune boost with the lo and high ***** only.

thewird

fd3s400438

Hello there I am new here and have a serious issue

I have a 1996 FD with a ported engine , 3mm apex seels , single HKS T04E turbo kit and many many more stuff

My problem is setting up my Greddy Profec B spec 2

I want to run about 1.25-1.3 bar of boost

I have tried to set the gain between 15-25% , the set gain from 0.5 bar up to 1.05 bar and the set boost from 50% up to 70%

All it does in all gears is to hit an overboost of 1.35- 1.4 bar and then it dies straight away to 1.1bar

So , what I am trying to say is that no mater what I do I cannot see constant , steady boost above 1.1 bar no matter what settings I dial in

ALL my connections and settings are ok

Please help

thewird

iTrader: (8)

Gain should be 10% (or less if your getting spiking, this is probably your problem)
Set gain should be under your target boost, I would set it at 1 bar for your target
Set boost is what you actually use to set your boost level, you'll have to play with this until you know what you get. Use 3rd or 4th gear to set the boost.
Also, make sure your not hitting overboost boost cut.

thewird

fd3s400438

I have tried all possible setting with gain starting from 5% up to 35% and set gain from 0.5bar up to 1.05 bar

The result is the same. I get an overboost up to 1.4 eevn 1.45 and it drops straight away down to 1.1 to 1.05 bar

It will not hold constant boost

So my question is this. Is there any chance that my setup ie my To4E or my wastegate spring are not big enough or strong enough to give me 1.3bar solid boost

From what I remember my T04E has 0.64AR inlet , 0.84 AR exhaust and my HKS wastegate that came with the kit had a 0.6 bar spring which we stiffened to 0.9 bar

Please help

thewird

iTrader: (8)

Use a gain setting of 5% for now then if its overboosting and then coming down. If its reacting always the same, that means that the boost controller is having no affect on boost control so there is something wrong with your setup. 0.9 bar spring is more then enough for 1.3 bar. What happens if you turn the boost controller off?

thewird

fd3s400438

the greedy is brand new and I installed it yesterday. I have always had a spec 2 but because I could not make it work I sold it and got a brand new just in case...

If I turn it off I see 0.9 bar

The unit reads pressure of the manifold , the valve has the COM on the wastegate and the NC of the turbo housing and also a second line to the wastegate

What are thinking?

fd3s400438

The boost control does do something cause when off I only see 0.9

When on and with currently

Set : 70%
gain : 35%
set gain : 0.5 bar

I get up to 1.45 bar from 2nd gear onwards but it dies straight away to 1.05-1.1 bar

I cannot get 1.2-1.3 constant boost no matter what I dial in

thewird

iTrader: (8)

Unhook the vacuum line going to the COM port and check to see if the wastegate is leaking by putting a pressure pump to that line and seeing if it bleeds off. It might possibly be an exhaust restriction as well, do you have a cat?

Do not use any gain as that causes problems most of the time. Just set it to 5% until you can get stable boost.

thewird

fd3s400438

no I dont have a cut it is straight through 76mm from top to bottom

I am also waiting for a 1 bar spring. will check the wastegate when it arrives

Can you think of any reason why i caanot see that boost

Somebody , a close frind who is currently running a huge single @ 1.5 bar producing 565 motor BHP suggested that my T04E might be too small for my engine and the boost I want it to produce

Can this be the case. Can this T04E be too small. I think HKS said it maxed at 400WHP and I have seen 416 @ 1 bar at the motor

After that I started raising the boost to realise that it will not hold over 1-1.1 bar from 5k onwards