Darren king

My 93 WRX is fitted with this turbo ,which i have been told is bigger than standard -can anybody confirm this or am i being told porkys!


Cheers

Daz

mattski

I think you're right, from what I can understand the older cars do have bigger turbo's...but I think this means more lag.

Quite interesting to watch as I had a bit
of a neck and neck with an MY98 UK car.

That seemed quicker initially but once
my turbo had spooled up I caught it no
prob.

[This message has been edited by mattski (edited 09 November 2000).]

Darren king

Thanks for your reply mattski

I take it you have the same turbo-what year is your car and could you tell me what boost it produces?

Also does this mean more power when using a chip upgrade.

Cheers mate

Daz

GavinP

Darren,

I also have an early WRX and would add to Mark's post that a better downpipe and induction kit can also reduce the lag (but not as much as a well-mapped ECU).

Later cars have smaller turbos which start producing boost at lower revs but can run out of puff at higher revs (5500rpm+).

Standard boost for an early car is 12-14 psi.

On my car, the ECU change to a BRD Link made the biggest difference in reducing lag.

Thanks

Gavin

R19KET

Darren,

The TD05H, is a very good turbo. It does suffer from lag, but this is due to,

1) it's big,
2) it's a sleeve baring turbo (IHI turbos are roller baring).
3) it horrible right angle intake.

A good replacement ECU will reduce the lag (subject to who maps it) and depending on how much you want to spend, there are mods to get rid of the right angle(quite expensive).

Best of all though, it's VERY strong, and can hold up to about 1.6bar .

Always choose a replacement ECU, and it's mapper, VERY carefully.

Mark.

Darren king

Thanks very much for the comments, it has a full scorpion system (no cats) and air filter which as stated helps reduce lag.

Im glad that you have confirmed that this turbo does have alot of lag as i wasn't sure if it was normal for it to boost at 3000+ revs.

Mark, my next upgrade is going to be a unichip do you think this will help pickup.

Gavin, does your WRX have fairly loud turbo whine as mine does.

cheers

daz

GavinP

Darren,

No noise from my turbo even with a Pipercross induction kit.

I would be inclined to give Roger Clark Motorsport a call on 01455 828610 and ask them to have a listen to it. They are in Leicester and are very friendly and knowledgable.

Thanks

Gavin

Darren king

Thanks Gavin

pat

Darren,

The TD05 seems to be the largest turbo ever fitted to a road Impreza, larger than the much praised VF22 (but presumably smaller than the VF15 used on the P2000). It does take a age to spool up, but when it does it's manic! It is possible to spool it up faster by backing off on the ignition timing close to it's pull-in speed but you need to be careful not to pull it in too hard or too soon, you'll fall of the stable operating area of the compressor map and it will surge. Not good!

Unfortunatley Subaru hampered the TD05 with one of the most convoluted intake paths I've ever seen in such a small space! This seriously upsets the airflow into the turbo :-( It is possible to convert the turbo into a straight entry unit, but it does require a later spec intake manifold to allow the intake duct to pass under the manifold! I have tried this and the difference is quite marked. Unfortunatley I haven't been able to test it above 0.8 bar due to a suspected ring failure on my engine (not related), needless to say it was pulling *really* strong at 0.4 bar and it was manic at 0.8, God only knows what it would have been like at 1.3 (previous boost level).

Depending on your intake and exhaust arrangements the TD05 can be quite "vocal". With an HKS induction kit and the 90 degree elbow it hisses / whistles up to about a bar, then it "screams". It will be interesting to see what happens when it goes over a bar with a straight entry....

Cheers,

Pat.

Darren king

Pat, thanks for all that info-it was just what i wanted to hear!

This explains why you wait for ages for it to pickup, then when it kicks in feels like someone whacked you in the back with a house brick!!!

My car makes all the noises as you said, screaming when comming up to maximum boost-i have been trying to find out if this was normal and nobody seems to have known. Im currently running 0.9 bar and am getting it fitted with a unichip soon, what boost do you recommend running with this turbo?

Another question is how come my WRX is only 240bhp if it has been fitted with this large turbo.

Thanks again pat, hope you can help me with this lot-you seem to be very knowladgeble with this set up.


Daz

ric

Here in Switzerland there is a tuner that prepares the Impreza (UK-spec) with the TD05 turbocharger.
It runs 1.5bar peak and 1.2bar held to the redline!!
I could test drive this car and it really goes like HELL. The power is around 300hp!
But there is a lot of lag and don't ask about reliability (they run the car like this on several racetracks (Nürnburgring and Hockenheim, driver was Marc Surer) without any problems).

greetings
ric

Dr Hu

Does anybody have a table of all the turbo designations on all model years??

This would be very useful....I was looking for one of these the other day as I have a turbocharger for sale in the <B>For Sale</B> section, but did not know what the letter coding was. I thought SIDC info pages may have had one but no luck.

It is not stamped on the turbo anywhere that's for sure!!

[This message has been edited by Dr Hu (edited 16 November 2000).]

Dr Hu

Duurrr!

Just looked on my turbo for sale and it a TD04L (std UK spec for phase 2 engines)

Sorry chaps.....still a chart would be useful!!

pat

Hi all!

Many questions :-)

OK, the screaming is an interesting one, mine is not the only car to do it (but I have yet to discover if the elbow affects it), neither Bob Rawle nor I were very concerned about it... my turbo has out-lived two engines now! Just goes to show that they are very sturdy units [or the engines are not? :-)] I don't think it's a problem, it's probably just the turbo working quite hard. It's worth just pressing a (long!) screwdriver against the turbo bearing housing and your ear to listen to the bearing, it should be pretty silent with no whining sound.

With regard to upping the boost etc, you need to consider many things! OK, the compressor map for the TD05H shows it will hold 1.6 bar all the way to the redline. I wouldn't recommend that you run that much boost, so the turbo won't be the limiting factor.

You need to think about charge temperature (the intercooler isn't that brilliant!). You can fit a later spec intercooler, but it's a tight squeeze on the standard throttle body. Going for a later manifold and throttle body gives plenty of room, but it's not a job for the feint hearted DIY-er :-) Simply changing the throttle body will give more room, and shouldn't be too difficult to do, but it will require the throttle position sensor to be replaced with a newer one, and wired in. This DOES work on a PossumLink and Pectel T6, but I can't guarantee that it will on a Subaru ECU / Unichip.

If you can't change the intercooler, think about water injection. Place a 0.5mm jet between the intercooler and throttle body, this will help control det and allow the car to run more efficiently (more ignition advance means that more power is being used, rather than being blown out of the exhaust!).

The amount of boost that you end up running will depend on many things, including the above on charge temps but also the compression of the engine, and how long you want it to last. Make no mistake, when you increase power, you decrease engine life, but increase smiles :-) I was running 1.3 bar with water injection; on the road that gave me about 330BHP and 310lb/ft of torque. That was with the original intake but with Legacy 480cc/min injectors; your grey 380cc/min injectors won't allow more than a bar at high revs!

That engine was running very well, but I killed it with a full throttle shift module; I've yet to do a post-mortem on it, but I suspect it either overspooled the turbo or upset the engine by advancing the ignition too quickly (it didn't bring the ignition back in gently after cutting during a gear change). Compression on the 3 good cylinders was rather good, so the map/boost itself was *probably* OK. Bob Rawle has been running similar boost for quite some time, but unlike me he had the sense not to build a full throttle shift module; his engine still works rather well :-) Remember you *WILL* need bigger injectors to run 1.3 bar to the redline, but the internals should take it. Or at least they seem to on STi II engines.

The power figure for your car is interesting. It could be that you have a higher compression, therefore more torque but less power. Check it out with a compression tester to be sure :-) As to how much a WRX will hold before it lets go, well, errr, pass :-) Probably 300BHP / 300lb/ft but it may be less, it may be more. It's worth checking the dyno site to see what others have done.

My next engine will hopefully be able to hold 1.6 bar all the way to the redline. I'de like to drop the compression down to about 7.8:1 but this won't happen for a little while. If the results which I got with the newer intake are anything to go by it will be quite entertaining. Just need to have a spare gearbox in case I blow *another* one :-)

As for what turbos were fitted to what, as far as I know all cars pre-1997 were fitted with the TD05H turbo, whether import or UK. In 1997 things get interesting :-) The UK cars get the TD04L, which they have retained to this day, and the Japanese ones go crazy :-)

The STi 3 was fitted with an IHI turbo, I think it's either a VF23 or a VF24. The WRX of that era would've been the same. The version 4 STi came with a VF24 turbo; some of the WRX cars of the same age came with a VF22. Starting with STi V the cars were fitted with the VF28 turbo, and the 22B was fitted with a VF23. The MY00 carried the same turbos across, but the MY01 seems to be using a VF29. UK cars are a bit of an unknown at the mo, possibly still TD04L but maybe they too have gone for IHI rather than MHI turbos.

Hope this helps,

Pat.