Custom TD03s - maybe the answer?

[Caveman]

Hi guys,

Firstly, happy new year!

I, like many of us, have been spending some time looking into getting my car as safely and as cheaply as possible up to 400 bhp.

As we all know, the key restrictor to more power is those blummin pissy little TD03 turbos that we have. The obvious answer is TD04, or TD05s, but upgrading to those is neither simple or cheap!

I decided therefore that improving the TD03 so that its capable of running more boost is possibly the answer. I don't want silly power as I'm not out to win races or challenge Skylines, but I do want the car to feel that it's running to its true potential.

I phoned round most of the big turbo houses over the last few days with little interest and then today I might have hit a result... Spoke to Turbo Dynamics in Dorset today and they said that if they can source the parts, then they should easily be able to rebuild the TD03s with custom parts as hybrids to run at least 400bhp, maybe more. What they do need though in order to try is the turbos to study so that they can see what they're up against.

If this works, then we will be able to run our VR4s without significant work or cost at the elusive 400bhp that we all crave!!!

I was quoted that a normal rebuild for 2 turbos would cost about £1000 all in.

So, the big question is - Does anyone have a pair of VR4 TD03s lying around so that we can suss this out?

Answers on a postcard...

Cheers,

Mart.

[Gly]

its been done before,

2 members here have had there td03's tweeked, (1 by one of nz's leading turbo guys)

they cant handle it,
the input shaft nut spins off, and chews up the turbos?

brad will be along shortly, to confirm??


and well 1000 pound or euro??
isnt cheap, i could get a garret 3540 for that cash, and have a good single turbo setup

[bradc]

yep, they just can't handle it. The housings are too small anyway, all of the inlets and outlets are tiny, there isn't much point to upgrading the stock ones

[SGHOM]

So, the big question is - Does anyone have a pair of VR4 TD03s lying around so that we can suss this out?

t.

I had a pair of perfectly good turbo's in my car boot for months. last week I chucked them in the skip.

[Nick Mann]

You can have them clipped for slightly better flow at higher revs. But they destroy themselves pretty quickly. Mine had been tweeked before I bought the car and they were dead less than a year later.

[mpau009]

Hi guys,
I, like many of us, have been spending some time looking into getting my car as safely and as cheaply as possible up to 400 bhp.

As we all know, the key restrictor to more power is those blummin pissy little TD03 turbos that we have. The obvious answer is TD04, or TD05s, but upgrading to those is neither simple or cheap!

I decided therefore that improving the TD03 so that its capable of running more boost is possibly the answer. I don't want silly power as I'm not out to win races or challenge Skylines, but I do want the car to feel that it's running to its true potential.
If this works, then we will be able to run our VR4s without significant work or cost at the elusive 400bhp that we all crave!!!

I was quoted that a normal rebuild for 2 turbos would cost about £1000 all in.

Hi Mart, i reckon youd be similar money to do a single turbo conversion, versus 1000 pounds for the turbo rebuilds. I am keeping tabs on my TD05 conversion costs, but havent put anything down in excel yet.

But if you discount the cost of the supporting mods for that power level, which i am assuming you would be considering:

- Fuel management
- Fuel Supply
- Intercooler and re-do pipe work

As long as you arent paying someone to do the work, i think it would be similar. Granted you will need to go to an external wastegate as the Td05 needs to be rotated to fit nicely, but a decent second hand TD05 and wastegate cost me $600 NZD, which is barely 250 pounds i think?, the rest of the cost bar the above is the piping and flanges, as well as some oil lines, water lines and fittings/blanking plugs etc, so i would imagine its similar money, for a setup that has more potential down the track in terms of upgrades.

As soon as i started having a decent look at the costs vs benefits, bearing in mind the mods /costs i already had planned it seemed simple.

Whether you go for TD05 or T3/T4 hybrid is another question

[Caveman]

Hi guys,

SOrry it's taken me a while to respond.

According to the guys at Turbo Dynamics, they would replace the internals of the standard turbo and possibly even machine the turbo housing if necessary to make it slightly bigger. He reckons a Garret T25's internals might fit for example.

Does anyone have a pair of old turbos that they'd be willing to donate to see if this can be done at least?

Mart.

[Nick Mann]

I will have at some point, but I need to keep them for a few months at least. Someone must have some old ones? I gave my last ones to Ben at Eurospec.

[Gowf]

I did have some, but they were in pieces and i left them at eurospec 6 months ago, so no chance of finding them

[Ryan]

T3/T4 hybrid is quite commonly used in South Africa but what exactly does it mean?

Does it use the exhaust wheel from one and the compressor wheel from the other?

[bradc]

Ryan - exactly

[Caveman]

Update.

I spoke to the guy at turbo developments today and he reckons he can machine out the VR4 TD03 housing and fit a TD04 inside. He was quite confident that he could do it.

I still need a couple of guinea pig turbos though as my car is a daily driver.

We should at least see is this can be done - this may be the easy way to 400bhp! No manifold work or fiddling required - just a straight bolt-on.

Any turbo donors out there?

Mart.

[Nutter_John]

I may have some soon , need to decide what i'm doing first

And they will not be able to fit td04 internals in ours as the difference in size is two great , but the gtr25 may be the option

[Caveman]

Another update.

Ok have spoken to Majestic turbos in the US who have experience of ugrading our turbos, as they are the same turbos that are fitted to the YAMAHA XJ-650 Seca motorbike.

The guy who does the rebuilding wasn't there, but they are going to get back to me with options as they've done this before. The main issue is with the tiny diameter of the turbo outlet and with the thin compressor shaft. Running a larger compressor can easily be done (and hence more boost) but the std shaft's life may be compromised.

Anyway, it looks like there IS light at the end of the tunnel and more powerful turbos can be run without having to go custom water/oil lines, custom manifolds, custom downpipes or relocating anything.

The future's bright!

Mart.

[Turbo_Steve]

I'm also of the belief that the TD03s can be hybridised: we've built some weird freaky units in the past that were surprisingly effective.

I'd be looking at the BMW TD03s, and the TD04-9bs, which my engineering friend seems confident can be "made to work"

I've mentioned the compressor nut coming loose, which he seems to think is a problem with the shaft heating rather than anything more serious. He suggested finding the right Ball Bearing cartridge would solve a lot of issues.

[Kieran]

Anyway, it looks like there IS light at the end of the tunnel and more powerful turbos can be run without having to go custom water/oil lines, custom manifolds, custom downpipes or relocating anything.

The future's bright!

Mart.

Mart - Have some rep.... It'd be great to get this one nailed. I'm not keen on all the fannying about that TD04s need, but I would certainly consider a set of Hybrid TD03s.

[Caveman]

Ok, more research done.

The more I learn, the more I'm beginning to go off the idea...

Hybridising the VR4 turbo can definitely be done by boring out the housing and fitting a larger compressor wheel - I have spoken to people who are familiar with our turbos and have done just that.

The issue is longevity. The weak link in the turbo is the compressor shaft which tends to shear at higher than standard boost.

I am therefore investigating what other possibilities there are whilst maintaining the standard engine layout and manifolds. I'm convinced there must be something for us - after all, there are literally hundreds of turbos out there!

Will keep you posted with my findings. On a mission now!

Mart.

[pitmac]

Val has pointed out in the past that the 335 BMW Has a TD03-10T-4.9cm Turbo which would be a good up grade for our TD03-7T or 8G which ever it is.
Use the cartridge or just the compressor wheel and have the compressor housing machined.
BMW turbo TD03L W 10TK3-4.9 pt no 49131-07005
Check out could be what some of us are looking for.

[jpnvr4]

Mart - Have some rep.... It'd be great to get this one nailed. I'm not keen on all the fannying about that TD04s need, but I would certainly consider a set of Hybrid TD03s.

heyyyyy! he get's a rep point 4 research ..... ok ..

I'm tryna get my turbos replaced ... so I may have 2 spare ones so pass out....
soon as I get mines let U kno

[Eurospec]

Hello guys,

Nick, i still have your old tubs here somewhere! And Gareths although his are in bits due to trying to make a rocket powered go kart out of them. (doesnt work).

But we do have now litterally hundreds of TD04 housings and i mean hundreds. Everything from 9b's 13g's, 13t's and maybe the odd 15g. What i havent done is put any td03 bits in touch with any td04, but to be fair they dont look like they would go.

TD04 is the way really for a 'reasonable' upgrade, but as we know the manifold is the issue. TD04 with a subaru fitment can go on to a galant manifold, but its a long way away from pretty or 'engineered'. I bet money it will work though.

Cheers,

Ben.