TD04 based hybrids install

[Tricky-Ricky]

In my opinion it seems like a whole lot of work for very little gain, thumbs up for trying something new though.

 

I cannot understand why you would want to swap a single GT3076R for a pair of hybrid turbos? A properly setup GT30R should make positive boost just as quick as the stock turbos and be more responsive than to a pair of hybrid turbos. Plus the GT30R should produce more power than any hybrid setup.

 

The limiting factor with any hybrids are the stock turbo housings and the sequential system, they are too restrictive to allow the turbos to flow enough gasses to make anywhere near 500hp.

 

I agree with these comments, and based on my experience with hybrids i really don't see the point, i actually suspect that they will be a disappointment, after what you are already running, but good luck anyway.

[Ian C]

I agree with these comments, and based on my experience with hybrids i really don't see the point, i actually suspect that they will be a disappointment, after what you are already running, but good luck anyway.

 

My old hybrids used to trap at 123mph at TOTB, running 1.4bar boost. They aren't that shabby if you get a good set But I concur that most people's experience with hybrids on here have mostly ranged between "disappointment" and "expensive disaster".

[wojtrek]

I've been reading a lot about hybrids here, but it seems there's a lot of variations. Some call a hybdrid basically a rebuilt turbo with stronger internals, but same efficiency. And on the other end of scale you have the GT28 hybrids. From what I gather, my hybrids are just a tad smaller that those GT28s, so when you say "disaster" etc which hybrids do you have in mind? Remember, that what I have is a TD04 hybrids made from UK turbos, not the Jspecs.

 

you lot are demotivating me with those negative comments on hybrids

[Ian C]

Don't get me wrong, I've always been a fan of hybrids as my Supra came with some installed. I never knew where they came from, previous owner didn't remember or have any records. But they were damn strong.

 

However it seems I lucked out and got the top end of the hybrid scale, as a lot of people (this is going back 4 or 5 years) got hybrids that weren't much better than stock, if at all. And others failed relatively quickly. So they fell out of favour, especially as better single turbo conversion kits cropped up and better engine management systems appeared to run them I gave up trying to defend them

 

But the majority of these were rebuild j-spec units, and as you say, were probably just slightly milled out for a 1 or 2mm bigger wheel or something. The lengths you are going to seem more promising, but the only way to tell is to build it and see what happens

[wojtrek]

cheers Ian, that's what I'm doing here, I guess we will not find out if someone doesn't test them well.

 

so, going back to my problem - I tried again, spent some time on my RR testing the MBC and EBC trying to get more boost, but failed again.

 

I guess I'm left with the option of testing boost leak, although even when I did the 'hose pull' mod, on both turbos, I get same 0.55 bar on first turbo, and the second didn't come online. I'll try to manually open the EGCV...

 

it's strange that the MBC mod is not working, it seems I have it connected ahs supposed to, the MBC is sitting there doing nothing. I can set the MBC to 1bar, with a hand pump, put it on the car and still get 0.55bar, like it wasn't even there

[wojtrek]

OK, I have solved one problem.

total noob I guess

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Since I have an Apexi BOV (leftovers from ma single setup), I left the stock blow off valve not connected, I just thought since I have the Apexi BOV I don't need that - wrong - the pressure found it's way trough there. So now, I have 0.9bar set on the MBC for the first turbo, and that's what I have. When in 5th or 6th, when floored it hits 0.9 bar as soon as 2700rpm give or take 100rpm.

But now, at transition, boost drops to about 0.35 and goes up to 0.8 and holds that until redline, with my AVC-R set at max duty cycle. So what I need to do now is find out why I can't really control boost past transtion. Or, why is it only 0.8 maxed out.

 

I have my avc-r connected like that:

http://www.mkiv.com/techarticles/avc-r/install/diagram.jpg

 

What could be the reason for low boost after transition? I have checked the EGCV, used a pump, it works.

[CanisLupus]

Had the same Problem with my AVCR Black Edition. ^^

Lower the duty to 70% but be carefull might Overboost. After that set it higher if needed.

Don't know why but mine did the same thing and soon i lowered it the Problem was gone and it controlled the boost normal

 

EDIT: Mine is Connected the same way

Edited June 10, 2010 by CanisLupus (see edit history)

[wojtrek]

mine's black aswell

 

I kept gradually adding duty cycle until reached max (90%), going back to say 60 drops the boost to 0.6bar...

I'm puzzled

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[CanisLupus]

Hm try changing the desired boost also.

Don't know really. It was the same thing mine did and when i changed duty and Boost suddenly it worked again ^^

 

One thing you could do would be Reinitializing it again and setting up everything again, including the gear judge things etc. Maybe helps

[Nic]

it's strange that the MBC mod is not working, it seems I have it connected ahs supposed to, the MBC is sitting there doing nothing. I can set the MBC to 1bar, with a hand pump, put it on the car and still get 0.55bar, like it wasn't even there

 

Have you tried temporarily removing the MBC and EBC and putting back to stock, taking them out of the equation will let you can see if the sequential system is functioning properly.

[Chris Wilson]

I would like to see them on a european car too..

 

My car is EDM, so I was considering the USDM/GT28 combo from S4S. Don't know much about the JDM mod, which probably is what interests you most.

 

But I think I read somewhere that someone in Sweden (IIRC) has the GT28 mod, but I'm not sure.

 

Talking about dyno numbers is pointless when it comes to comparing them with american dyno numbers. They not only measure power at the wheels, which is just wrong (you have different power in different gears, if you use different tyres, the power will be different etc.) but also will tell you, that when you go to a dyno made by one company rather than another it will show more power (Dynojet and Mustang dyno IIRC). What I have noticed is that over here in Europe, people should be happy to get the american wheel horsepower at the crank. So if the GT28 mod is netting 550 wheel power, I would expect no more than 550 at the crank... I wish I knew the numbers for my TD04 hybrids, Swampy says the americans say it's 550 at the wheels, well... Since they are a bit smaller than the GT28's are, and I don't want to use methanol and other crazy fuel and mods, I think that if I could have something just shy of 500 at the crank - that would be great.

 

 

You speak a great deal of sense on chassis dyno figures. I know what my old Skyline engine gave on a Superflow engine dyno with full and accurate correction figures, and what it supposedly gave on two chassis dynos. I also know which figures I believe If everyone with a chassis dyno print out in the US were given free labour and engine dyno time the sea level would rise with the tears of frustration and anger at the sight of proper figures.

[Chris Wilson]

OK, I have solved one problem.

total noob I guess

/vbb/images/smilies/bbcode_oops.gif

 

Since I have an Apexi BOV (leftovers from ma single setup), I left the stock blow off valve not connected, I just thought since I have the Apexi BOV I don't need that - wrong - the pressure found it's way trough there. So now, I have 0.9bar set on the MBC for the first turbo, and that's what I have. When in 5th or 6th, when floored it hits 0.9 bar as soon as 2700rpm give or take 100rpm.

But now, at transition, boost drops to about 0.35 and goes up to 0.8 and holds that until redline, with my AVC-R set at max duty cycle. So what I need to do now is find out why I can't really control boost past transtion. Or, why is it only 0.8 maxed out.

 

I have my avc-r connected like that:

http://www.mkiv.com/techarticles/avc-r/install/diagram.jpg

 

What could be the reason for low boost after transition? I have checked the EGCV, used a pump, it works.

 

You may need to put a restrictor pill in the wastegate pressure line. The MKIV uses large internal diameter wastegate hoses, and even with a boost control valve on full duty cycle the engine produces enough air FLOW down the pipes to overwhelm the valve and PRESSURE in the gate rises pretty much unchecked. By restricting the flow with say a 2mm hole in a "pill" in the pressure hose you reduce FLOW and cure this. A very common problem on some engine / boost controller set ups and maybe worth a try.

[Ian C]

You may need to put a restrictor pill in the wastegate pressure line. The MKIV uses large internal diameter wastegate hoses, and even with a boost control valve on full duty cycle the engine produces enough air FLOW down the pipes to overwhelm the valve and PRESSURE in the gate rises pretty much unchecked. By restricting the flow with say a 2mm hole in a "pill" in the pressure hose you reduce FLOW and cure this. A very common problem on some engine / boost controller set ups and maybe worth a try.

 

I'm intrigued My setup has always had a sorta problem with the boost production tapering off as pressure increases, I couldn't tune it out even with very aggressive response settings, are you saying this is because I need a restriction in the hose that provides a pressure reference to the wastegate diaphragm/boost solenoid?

[Chris Wilson]

Possibly, yes, in the hose from the turbo compressor scroll to the wastegate controller to restrict air flow. One of my little secrets has just been revealed.....

[Ian C]

Well I might just have to give that a try and see what the boost build curve looks like afterwards

[Scott]

To the op.

 

Is it possible you have the AVCR connected to the wrong part of the actuator? There are two connections very close to each other. One is at the top of the actuator and one is at the front. You want to be connected to the one at the top.

 

When connected to the latter you won't make any difference to the boost pressure

[wojtrek]

OK, update...

 

first of all, a bit thanks for all trying to help - much appreciated!

I have spent many hours, again...

Chris, dyno, dyno numbers etc. - a lot to write about, maybe I'll post my observations somewhere, sometime. I need to solve my problem first - it's killing me... thanks for the tip on the hose diameter, I'm using smaller hoses anyway, but not that small. But unfortunately I don't think it's the cause if my problems.

 

OK, here goes...

I have put everything back to stock - took off the MBC and APEXi AVC-R, to see how the car behaves. So, I have 0.8bar on the first turbo (which is a bit high, should be 0.7) and at transition, boost drops to 0.35bar - too low - and slowly rises up to about 0.7 - 0.75 max, which is 0.1bar short of what it should be... I don't get it.

 

I have tried many things - I have tested all actuators, pressurized them and checked if they open at correct pressure levels - they do. I have checked the VSVs for correct resistance - all OK.

There are a few weird things though:

- when I put the AVC-R only, as the instruction says (the diagram I posted a few posts back) when I raise the boost (and I can only get it from 0.75bar to 0.85) the pressure also rises on the first turbo - if I'm correct, this shouldn't be happening? So, what I have is higher boost on the first turbo without doing anything to raise it. any ideas why this is happening?

 

- with my AVC-R maxed out, what I get is about 0.95bar right after transition, just for a fraction of a second, after which it drops to 0.85bar and holds that to redline,

 

- I have thought that maybe the second turbo is bad, and not working as it should hence the low pressure, but if the turbo was bad, it would probably not hold rock solid 0.85 to redline, would it? A dying turbo would, I presume, drop pressure as the revs got higher?

 

- to check the max boost I can get from these turbos I have tried the bleeder T mod, didn't help. so I pulled the hoses off and I have pressurised the wastegate actuator so it stayed open - this, on a normal car, means crazy boost 1.5bar +, am I right? Well, I think I tried that once a year or two ago, to see what happens, and I got crazy high boost. but today when I tried that I had the same story with my boost - like with the AVC-R only - the car was of course in parallel mode, so the boost slowly went up, to hit 0.95bar for a fraction of a second, and held rock solid 0.85 to redline. is this possible? same boost pattern in parallel mode, with the wastegate fully open and all hoses pulled, as in sequential with all piping put on and just the AVC-R?

 

it seems I have tried everything - I have no clue as to what is happening with my car...

any ideas?

 

Oh, btw, since I'm doing all testing on my rolling road, I have measured it while I was testing.

so, stock car, with weird boost (0.8 first turbo, then 0.75 after transition) - 342bhp crank and 415Nm (305ft.lb). after I put the AVC-R on and maxed it out (the 0.9bar first turbo and 0.85 after transition) I had 420Nm (309ft/lb) at 2800rpm! then 480Nm at the 0.95bar 353ft/lb peak around 4200rpm and 352bhp...

[CanisLupus]

Just to assure there are no unusual squeeking noises?

Play in the bearings? BOV is also ok and not losing pressure or opening prematurely?

 

Wasn't it the other way round? If the wastegate stays closed the max boost rises. So if you open it it will restrict boost to the minimum the Wastegate can.

[Scott]

Again, are you on the correct location for the wastegate actuator? There are 2.

 

If you hold the wastegate closed you will get crazy boost. Open you will only get whatever your car maxes out at at full chat, and it will take a while to get there. Most cars hit 1.5-1.6ish iirc. With the wastegate closed I would guess your turbos would pop before you hit a maximum.

[wojtrek]

I will check the BOV, maybe it does open too soon...

 

And yes, my AVC-R is connected correctly - if the diagram I posted above is correct... it's connected between the turbo and the nipple on the actuator, the one pointing up (looking at the car).

 

but anyway, I still don't know, why I have higher boost on the first turbo than I should have, why is there such a pressure drop at transition, and why the pressure rises to only 0.7-0.75 bar after transition...

[Wez]

If memory serves me correctly all exhaust gas will be used to spool turbo one and then as the transition period starts some gas is bled away to pre-spool the secondary and then once complete all the exhaust gas is used to keep both tubbys online.

 

There are three VSVs that control this operation as I remember fiddling with the RPM points at which they operate on the AEM using stock jspec turbos.

 

Are these turbos too big, do you have more information on them?

[Chris Wilson]

I am with Wez here, if the front turbo isn't producing the expected boost at the pre set ECU change over point it may well never get its act together, control wise. You may need a different control algorithm in the software. Do you KNOW others run this set up with no issues?

[wojtrek]

I don't think these are too big - the GT28 hybrids Speedforsale is selling are even bigger, and they work OK with the stock system.

 

also, when all is reverted to stock, no MBC or EBC etc. I get 0.8bar of boost before I reach 3000rpm (2500rpm-2700 IIRC) so even more than a bone stock car. So it can't be that I'm not getting enough boost o prespool the second turbo.

 

I don't know anyone who runs this setup, but I remember reading about a similiar setup on the web. I can't imagine somebody selling a turbo kit that won't work

 

am at the workshop now, will check for boost leak now

[Chris Wilson]

I can't imagine somebody selling a turbo kit that won't work

 

 

This fella' obviously doesn't get out much.... We had a company over here that SPECIALISED in them.

[wojtrek]

hope they didn't make td04 hybrids for supra

 

i did a boost leak test, 2 hoses were leaking a bit, but nothing major I guess. i'll see if it changed anything, back on the dyno...