2J + TTC all day, everyday.

[Hengsta]

Howdy lads,

I have done what Brett did years ago with the rear turbo mod to his 2J MZ** Soarer and just wondering if any of the sensors/actuator for the sequential setup is needed to help run the turbos? This goes for the loom/plugs aswell as i want to cut them all off so it be abit neater.

Also there are three hoses out lets on the rear turbo wastegate actuator which one is which? Are they all needed to be used? if so, can anyone tell me which one goes where? All i know is i will have to tap a nipple/hose outlet on one of the rear turbo pipes but not sure which hose outlet goes onto the wastegate actuator.

Sorry if this didnt make any sense as im half alsleep at the moment lol

Trying to get the engine back together now as i have been dying for some boost and skids.

Any help much appreciated lads.

Cheers,

Heng

[woggin]

There is only 1 wastegate to control boost...thats on the front turbo, the rear one is a exhaust bypass valve, soooo not needed!! just rip EVERYTHING out, the only thing you need is the front turbo wastegate, thats it!

[Hengsta]

Even after i did the rear turbo wastegate mod aswell?

[Hengsta]

Ok i have checked..

There is only two outlets on the wastegate actuator not three as i mentioned.

Anyone?

[wilbo666]

What you have done is turned the rear turbo's 'prespool' into another wastegate! You can still run the turbos in sequential mode

You have a few options in regards to how to wire the VSV for it. The hosing can remain as factory, no need to change that at all.

For some background info the stock ECU actually works like an electronic boost controller to reduce wastegate creep and keeps/forces the front wastegate closed via it's VSV to bring boost up quicker (avoiding wastegate creep).



So one option is to trigger the VSV that was used for the prespool actuator off the same signal as the VSV for the wastegate. This could be done at the ECU by cutting the wire that comes in on pin 38 (VSV3) on the 80 pin plug and connecting it to the wire that goes to pin 60 (PMC) on the 80 pin plug

The transistor inside the ECU I looked at was marked "E1A4A" for the PMC pin (pin 60), and I've been unable to find out how much current this transistor is capable of sinking... so connecting the two VSV's in parallel might blow this transistor. The VSVs have a resistance of 22-26ohms, so ~1A at 12V is required for two VSVs in parallel.

If you do this you will effectively have made the wastegate twice as large and the sequential system will operate in a very similar fashion to factory, including the avoidance of wastegate creep - there won't be any prespool of the rear turbo of course.



Another option is to unplug the VSV for the 'prespool' actuator (Now the rear wastegate actuator). This will make the rear turbo 'wastegate' act like a conventional wastegate and open when the pressure on it's diaphragm reaches it's set value, there won't be any avoidance of wastegate creep.

However it might be found that if both wastegates are controlled via the ECU to reduce wastegate creep a boost spike occurs, and perhaps having the rear VSV unplugged is the better solution


I'd be interested to hear your results as I still haven't gotten around to putting my modded turbos on

Cheers
Wilbo

[Hengsta]

What i was trying to get at is i dont want to run in sequential mode at all.

I want it TTC mode always. Thats why i did the rear turbo wastegate mod so it doesnt over boost.

What VSV are you speaking of, theres like 4 of them sensors thing lol.

Will i need to run any of the VSV even if i did the rear turbo wastegate mod?

[wilbo666]

What i was trying to get at is i dont want to run in sequential mode at all.

I want it TTC mode always. Thats why i did the rear turbo wastegate mod so it doesnt over boost.

What VSV are you speaking of, theres like 4 of them sensors thing lol.

Will i need to run any of the VSV even if i did the rear turbo wastegate mod?

I personally don't know why you'd want to get rid of the sequential system, but anyway

Converting the rear prespool valve to a wastegate doesn't change how you have to convert to remove the sequential turbo system. The usual methods of removing the sequential turbo system apply... google should help

I'll say it again. Converting the rear turbo prespool actuator to be another wastegate has no effect on the sequential turbo system other than to of course remove the prespool of the rear turbo.

Maximum boost should be the same regardless of sequential or parallel turbo mode.

Anyway you can...
1) Leave all the VSVs and run a switch to change between sequential and TT mode...this is what I'd do so when you realise that the sequential system was in fact awesome you can change back to it
i.e. http://www.toymods.org.au/forums/showthread.php?t=39941

2) Use 1 way valves to setup TT (Google)

3) Physically,
>Remove EGCV actuator and VSV
>Remove the flap from the EGCV (or wire open)
>Remove IACV actuator and VSV
>Remove the flap from the IACV (or wire open)


Regardless of how you get rid of the sequential turbo mode you'll want / need to do one of the following to control the new rear wastegate.

Unplug the VSV for the Exhaust Bypass Valve (Prespool) which is the large VSV bolted to the rear turbo intake pipe OR you can wire this VSV up to be driven by the same signal as the Wastegate VSV (Large VSV mounted to lower front of front turbo) as I talked about above.

You can remove the VSV for the Exhaust Bypass Valve if you decide not to have it controlled by the wastegate signal from the ECU... and there is nothing stopping you removing the front wastegate VSV if you want to stop the ECU from trying to bring on boost quicker via reducing wastegate creep...

Short answer = you can remove ALL the VSV's related to the sequential turbo system if you wire or mechanically remove the EGCV and IACV flaps, plug the lines that come from the second port on the actuators for the 'wastegates' that goes to the VSV and block the other now unused VSV connections.

Image taken from this thread http://www.toymods.org.au/forums/showthread.php?t=47226


Cheers
Wilbo

[Hengsta]

Short answer = you can remove ALL the VSV's related to the sequential turbo system if you wire or mechanically remove the EGCV and IACV flaps, plug the lines that come from the second port on the actuators for the 'wastegates' that goes to the VSV and block the other now unused VSV connections.

THANK YOU VERY MUCH!! That is all i wanted to know and now you have answered my question.

I have bashed/cut/hit and removed the IACV flap lol and EGCV flap i wont be putting back on.

To be honest with you, i really dont want the hassle with the sequential wires/hoses/setup crap as its to much of a headache for me lol and thought i will just run it in TTC mode all the way untill i have some $$$$ for a single turbo. If i had the money, the twinies would have gone a long time ago and chucked into the bin and would of been replaced with a T04Z.

So with the rear "so called wastegate actuator" (Exhaust bypass valve actuator) what hose outlet do i use on that to plug it into the front wastegate? also there is two hose outlet from the front wastegate? which one is which? very much confusing me .

Once agian Thanks for the help wilboo much appreciated mate + rep coming your way.

[wilbo666]

So with the rear "so called wastegate actuator" (Exhaust bypass valve actuator) what hose outlet do i use on that to plug it into the front wastegate?

You don't need to 'plug' it into the front wastegate hose as there is already boost pressure plummed to it.

If you follow the lines on the engine you will see that there is a pressurised line going to the actuator already, which is exactly what you want

The easiest thing to do is simply unplug the electrical plug for the for the Exhaust bypass valve actuator VSV, and leave the hoses as factory.

Otherwise you can block the hose that goes to the VSV...

also there is two hose outlet from the front wastegate? which one is which? very much confusing me .

There is also two hose outlets on the rear actuator also

They are both the same - i.e. if you blow through one air will come out the other!

This is what the stock ECU uses to avoid boost creep. The stock ECU will open the second nipple on the actuator and connect it to atmosphere (intake) effectively short circuiting it and not allowing enough pressure to build up to actuate the actuator

You'll want to block the one that goes to the VSV.


This website should make it clearer...
http://www.max-boost.co.uk/max-boost/supra/turbo.htm


Cheers
Wilbo

[Hengsta]

One thing i didnt mention is the engine was in pieces and just got the turbos on couple weeks ago. Which means all hoses and drain pipes and everything else was disconnected (for like 5 if not more months) and thats why i have little to no idea where the hoses and stuff goes to lol.

But that site you linked has got EVERYTHING i need to know.

You sir is a legend, Wilbo.

Much appreciated for your help.

[woggin]

Short answer = you can remove ALL the VSV's related to the sequential turbo system if you wire or mechanically remove the EGCV and IACV flaps, plug the lines that come from the second port on the actuators for the 'wastegates' that goes to the VSV and block the other now unused VSV connections.

Thats pretty much what i said....but more simply.....rip everything out, dam i hate being young....nobody listens or pays attention to you!

good to see you got it sorted!