Did the TTC mod on my Supra, noticed a few things, need some help

[Guest supra&starlet]

Full boost, TTC or sequential should be 1.2 bar max

 

WOW I am Way under that. Is it cause of the restrictor ring in the exhaust?

[Benjy]

It's because you're not running a boost controller. Before my boost controller was fitted I was maxing out at .9 bar with a 1.2 bar restrictor ring and 3" exhaust system.

 

Get a boost controller fitted before you do ANYTHING else.

[Guest supra&starlet]

ok thanks for the reply, would it work if i purchased a High-end Manual boost controller?? I mean i do hear that many manual boost controller's tend to cause boost spike, and have un-even boost curves until redline, but my friend he have a high-end 140 dollar manual boost controller on his 300zx and is very good. Im wondering if it will be okay on the supra and safe to use??

 

And does anyone have pictures of how to install a boost controller on a supra? I have been looking everywhere and cannot find a clear thread with pictures. I have a general idea of where to hook it up, but its better to have pictures from someone who has already done it.

 

 

Thanks, Cristian

[TubbyTwo]

Get a decent electronic boost controller.

 

Only real way to ensure accurate consistant boost control.

[Guest supra&starlet]

i finally found a picture on the forum of how to install a electronic boost controller.

 

I will be re-installing my HKS EVC 4 boost controller back into the car, now that i know exactly how to install it. This way i will be able to control my boost level's. I will also change the VSV sensors on the front of turbo 1. Once i get the boost controller running and working i will just set the boost to 1 Bar and leave it at that. It should create a nice even boost curve and should stop the car from spiking boost soo much. I will report back once i fully install my HKS EVC 4 electronic boost controller and let you guys know the results

[Guest pwings18]

Can you show picture you found ?

Or put yours when you will re install your boost controller ?

 

Thanks.

[TubbyTwo]

If you look online you can find the manual for the evc as well. I have the evc 6 and its time consuming to set up but with 4 or 5 test runs I have it sorted. And havent needed to touch it again since.

 

Great bit of kit.

[Guest supra&starlet]

I found this picture on the forum. It is very useful to anyone who is looking to hook up electronic boost controller.

 

 

 

 

 

The only thing that is different from that picture is that the HKS EVC 4 Ports are not named the same, the HKS evc 4 ports are numbered and there is 4 of them. I used the HKS EVC 4 installation instructions online so i could figure out where port 1,2,3 got connected to based on the diagram i have installed. It also helped me because i have in my garage another complete pair of JDM twins for the supra so i used that as a reference. I will bump this thread if i have any other questions, or once i fully install it and hook it up to my car

[Guest supra&starlet]

OK so here is update.

 

I install full HKS EVC4 boost controller today and it fully works.

 

However problem has occurred

 

I changed the VSV sensor on the first turbo where the exhaust actuator connects to it by vacumn hose, and i believe it is faulty VSV??

 

Because now with the car, the second turbo does not kick in sequencial mode. I feel as if the actuator flap does not open because i do not hear the exhaust note change. I believe the boost controller fully works, because the car when i floor it from 2000rpms to about 3500rpms it boosts to 0.65-0.66BAR of boost, however after 3500rpms all the way to redline, my boost drops to eventually 0.4BAR, and the second turbo does not kick in??

 

 

Two days ago when i had car in TTC mode both turbos were working and it was pulling extremely strong, but now back in sequencial mode with the VSV sensor changed now it doesnt even open second turbo up, and before i put it in ttc mode both turbo's were working fine on the old vsv sensor

Edited February 28, 2014 by supra&starlet (see edit history)

[Guest supra&starlet]

The car is J-Spec, so it has smaller injectors, smaller fuel pump, smaller un-controllable waste gates

 

Mods of car:

 

HKS EVC4 Boost controllet

 

Apexi Midpipe, Catback exhaust

 

Egay autobahn 88 JDM downpipe

 

Mines Tuned stock ECU

 

Blitz front mount intercooler

 

Aristo CT20A Twin Turbo's

 

Brand new vacumn Hoses all around

 

All Cat's removed (car is straightpiped with exception of a muffler on the catback to keep noise down)

 

Anyways i have been experiencing some problems that the search button cannot really answer for me this time.

 

Before installing the HKS EVC4 boost controller i was experiencing some problems with the car in sequential mode where i would only hit 0.4BAR of Boost with first turbo then second turbo would open up and it would jump to about 0.85BAR of boost.

 

Putting that aside, i had an extra sequencial turbo system sensors laying around and i replaced those guys then i installed the HKS EVC4 electronic boost controller

 

I was experiencing that problem where it would hit 0.4BAR of boost with second turbo, then i did the 5 minute TTC conversion and the boost spikes very high (to about 1.45 BAR)

 

I figured out how to work and RESET the HKS EVC4 however it does not control my boost. I have done it as per instruction manual and i found a website that says how to properly install it and set it up, i have done all of that it still does not control boost at all

 

The newest problem is that in sequencial mode with the boost controller installed my car does not get that 2nd turbo rush anymore. It basically boosts to 0.5BAR or 0.8BAR depending on boost controller setting (ever since i replace VSV sensor) however when it reaches 4000rpms where it should open the exhaust flap to allow the second turbo to come online, mine does not come online, it basically boosts with first turbo to 0.5Ar or 0.8BAR then when the 2nd turbo SHOULD be coming online my boost drops to 0.4BAR all the way to redline.

 

I said fine i will replace the VSV sensor that is responsible for opening and closing exhaust flap, which i did and i still get the same symptoms where my second turbo does not come online.

 

In sequencial mode it appears that my HKS EVC4 does control boost because i had it set at 0.5BAr then i set it at 0.8BAR and what i noticed with first turbo is that it actually hits those boost levels

 

Soon as i go to TTC mode the boost levels are no longer controllable and it jumps to 1.45BAr of boost.

 

Im not sure if its a restrictor ring or not but in my downpipe gaskets i had a old gasket measured and it was 2.9" in diameter.

 

 

All of these tests and runs were done in 3rd and 4th gear, and the temperature outside was 9 F.

 

Im just wondering what the hell is going on with my car

 

Why can i not control boost in TTC mode?

 

Why does my 2nd turbo not come online in sequencial mode?

Edited March 5, 2014 by supra&starlet (see edit history)

[Justin Bieber]

A restrictor ring is only about 2" diameter mate, as your car has no restriction in the exhaust when its in TTC and both turbos are generating full boost they are just blowing the #1 wastegate wide open and still generating the 1.5 bar of boost you are seeing, you need to put a restrictor ring to literally limit the boost the turbos can create by causing a big restriction in the exhaust, this combined with the wide open wastegate will bring the boost your turbos create right down to whatever the restrictor ring is designed to provide, normally 1 bar or 1.2 bar, and then the boost controller can now begin to close the wastegate and raise the boost your car produces, giving you your boost control.

 

At a guess I would say you do have boost control without the restrictor ring in place, but it would be at a boost far beyond any of us would set our controllers too for fear of destroying the turbos, as the controller would still be able to close the wastegate, but probably somewhere in the 25psi+ range. If you set the controller any lower than that then because the turbos produce so much boost without a restriction in place the controller would never have to close the wastegate to generate more boost, giving the impression you have no control, when really you do, its just at a stupid level

 

Unfortunately I can't help with sequential mode problems! Good luck!

[Guest supra&starlet]

thanks for the clear reply, i appreciate it.

 

 

So my guess after reading up some more, is that i would have to make my self a restrictor ring that is exactly 2" in diameter which should bring the boost levels down to about 0.9-1.1BAR.

 

My next issue is why i am not getting 2nd turbo to come online

[mellonman]

not sure if you have seen this thread but im sure it will help http://www.mkiv.co.uk/vbb/showthread.php?35926-The-sequential-system

[Guest supra&starlet]

not sure if you have seen this thread but im sure it will help http://www.mkiv.co.uk/vbb/showthread.php?35926-The-sequential-system

 

thanks i was reading up on that the other day, I am definitely having problem #2 in that thread where i do not get 2nd turbo rush and it just dumps all of the boost instead. It says there that it has to do with the exhaust gas flap not opening exhaust to the second turbo which is exactly what i am experiencing. I have replaced the VSV sensor and it did not make any difference. I am going to un-hook the boost controller and see if that makes any difference

[mellonman]

thanks i was reading up on that the other day, I am definitely having problem #2 in that thread where i do not get 2nd turbo rush and it just dumps all of the boost instead. It says there that it has to do with the exhaust gas flap not opening exhaust to the second turbo which is exactly what i am experiencing. I have replaced the VSV sensor and it did not make any difference. I am going to un-hook the boost controller and see if that makes any difference

 

have you replaced all your old vacuun pipes both side and rear of the block , these are also a known issue with 20 year old rubber pipes ,

[Guest supra&starlet]

have you replaced all your old vacuun pipes both side and rear of the block , these are also a known issue with 20 year old rubber pipes ,

 

i have only replaced the turbo side of the vacumn lines. And i have not replaced the vacumns behind the block. How do i reach those vacumn hoses? They look like a very huge challange to do replace it

[mellonman]

well when i say at the back of the block there are some at the very back near the second turbo they then attach to solid lines that go around to the intake side , to reach them you have to have a very long set of long nose pliers , the ones on the intake side can be done quite easily with some patiance

[Guest supra&starlet]

well when i say at the back of the block there are some at the very back near the second turbo they then attach to solid lines that go around to the intake side , to reach them you have to have a very long set of long nose pliers , the ones on the intake side can be done quite easily with some patiance

 

when i replaced the turbo's 8 months ago those two little hoses that are hidden beside the firewall i double checked them and they were in good condition, they were still flexible and showed no signs of brittleness

[Guest supra&starlet]

So today i messed around with it some more.

 

I tested out every single sensor and each sensor had voltage coming through the wiring harness

 

I then took each VSV sensor and hooked it up to the car's battery and every single one was clicking and working like they should.

 

I realized my wiring harness connector on one of the VSV sensors the positive cable was pushed back and it wasnt making contact with the VSV sensor, so i pushed that positive connector so it was making contact with the VSV sensor

 

I switched the vacumn hoses for the EGCV valve and every time i hit boost the exhaust flap was opening but it was getting stuck open

 

I switched the vacumn hoses back around for the EGCV VSV and voila it was working perfect again

 

I did a few pulls and i cleaned out all of the carbon build up and she runs like a charm now. 1st turbo is online at 2100rpms 2nd turbo is online at 4000Rpms exactly.

 

 

I am still overboosting when second turbo comes online, today i hit probably 1.3BAr of boost when the second turbo came online. So i will need to build my self a restrictor ring gasket and slide it in between the downpipe and the midpipe

 

I will be buying some exhaust gasket material and i will be cutting it and making it myself at home. How wide should the hole be in diameter? And what diameter restricts boost to what level? For example 1.5" diameter restrictor ring limits to 0.8BAR while 2" diameter restrictor ring limits to 1.2BAR

[Guest supra&starlet]

also where can i order a 1.0 BAr restrictor ring? I have been looking on whifbitz website but cant find the restrictor ring by its self only have found it with the down pipe and mid pipe kit. Does anyone have a link?

 

and if i cannot purchase one, then what material should i use to make one at home in my garage?

Edited March 12, 2014 by supra&starlet (see edit history)