(Another) Turbo Query

[aragorn]

I've been looking at the various K04 threads and the basic concensus seems to be to use the K04-015 which is designed as an upgrade turbo specifically for the A4 1.8T

I'm trying to work out what exactly stops us using the turbo from the TT225/S3 engine and ive had a look for some pics of the TT turbo.

http://cgi.ebay.com/ebaymotors/AUDI...318QQhashZitem170242124103QQitemZ170242124103

That auction has some good images of the TT turbo and it seems to me the only issue is that the compressor housing is pointing upwards. Surely it would just be a case of loosening/removing the compressor to centre housing mounting bolts, and rotating the compressor housing round. It even looks like there are already suitable mounting lugs to allow the actuator to be positioned in the same place once the housing has been rotated...

Am i missing something really obvious here?

 

[docurley]

I lay money on it that the bolts will only line up one way and to be honest I'm sure it's already been tried.

Look like you would also need a custom exhaust as it also looks way shorter.

 

[aragorn]

it would strike me as very unlikely the compressor housing would only fit on one way, looking at it it will probably fit on in 90degree increments, which should be fine.

Ok its shorter and would require some exhaust modifications, but surely this is a reasonable compomise seen as the TT turbo can make more power than the k04-015? Arent they good for 270-280ish hp?

Could probably pick up a low mileage one and some injectors for less that a k04-015 and end up with more power, seems like its worth the extra hassle to me?

 

[Blue_Thunder]

If you rotated it 90 degrees, wouldn't the actuator then be in the wrong place?

 

[aragorn]

Yup but the actuator unbolts, and if you look at the pics of it there are lugs on the opposite side of the housing that would take the actuator after its been rotated. (to clarify it would need rotated thru a full 180degrees to fit the longitudinal engine)

Failing that the K03 actuator bolts to a bracket thats held on by the bolts that hold the compressor housing on, and i'm sure it would be easy enough to fabricate a similar bracket (or perhaps the K03 part would fit right on)

 

[brendan]

it would strike me as very unlikely the compressor housing would only fit on one way, looking at it it will probably fit on in 90degree increments, which should be fine.

that's alright as long as the bolts are in a square pattern. in that pic above (although it might be the angle the photo was taken at), the two bolts at the 'top' are close together than the two at the bottom of the pic.

 

[aragorn]

the centre housings are standard parts, you probably find the same housing used over a huge range of K04 turbos on various cars, vans etc.
it would make no economical sense to design it without equal spacing of the bolts, as it means there is less chance of the part being reusable in a different application

I guess everyone just takes the easy option with the -015 but that doesnt mean that the more common 020/022/023 turbos wont fit, but since the 015 dominates most forums it seems very hard to get the info on why. Ive never actually found a reason, with most posts or pages just saying "they only fit transverse engines". Yes there are issues to overcome, but there are similar issues to overcome to fit a -02x to a transverse engine, yet theres tons of info available and people are happy enough to do it.

 

[docurley]

Couple of bits of info.

http://www.audizine.com/forum/showthread.php?t=152991&highlight=K04-23+A4

http://audizine.com/forum/showthread.php?s=&threadid=60765

 

[aragorn]

still lots of vague hand waving as to why it will not fit bar the one comment about the manifold flange.

Does that mean the Manifold to Turbo flange on the -02x turbo is larger then? which i guess would explain the higher power levels and it not fitting. Any reason why the TT manifold wouldnt fit the A4?

 

[jcb]

what is different between the KO3s and KO4 in terms of compressor and turbine wheel size?
normal way of squeezing more power out of a turbo is to up the compressor wheel size first (eg GT28rs and GT2871 both have the same turbine wheel but bigger compressor wheel resulting in a 75bhp hike in range)

could you swap the Ko4 compressor housing onto the Ko3s?
sure someone has done this, never looked

 

[aragorn]

i'd imagine thats probably what BW have done with the k04-015 upgrade turbo, either by fitting a k04 housing, or my machining out the k03 housing and using the k04 compressor wheel?

as afaik the k04-015 and the normal k03 look identical externally

 

[docurley]

Well my hybrid K04-15 had to be bored out to take a K04-23 shaft and larger wheel so I dont thinks a Ko4-2's wheel in there.

 

[951]

So how easy it it to remove the turbo from the car ??

 

[Andy.B]

As JCB said if the core of the turbo is the same whats stopping you getting a TT turbo, then taking it to Turbo Technics and getting the compressor housing machined out and even the exhaust housing of a k03 to accept the k04 core? I have an ol K03 lying about just if its just a case of machining an ally comprssor housing then it will be a very cheep way of getting a K04 turbo.

 

[docurley]

This is what Scrolls does

 

[PaulJC84]

what is different between the KO3s and KO4 in terms of compressor and turbine wheel size?

K03s rear

K04 rear

K03s front

K04 front

 

[Andy.B]

So you tell me this is what scroll does... now do we have to send the turbos off to europe to do them or can someone now do this in the uk?

Machining out compressor housings must be quite cheep engineering to do at a turbo center if we supply parts?

 

[Lee Goodall]

..this is a new SP51R turbo from Scroll Products which is also based on around a K03 but with modified internals (very similar to the K04-015) but this also has twin oil feed bearings.

 

[aragorn]

the point is the K04-015 is basically a K03 with modifed larger internals, as you can see in the pics they are externally the same. The k04-02x is a larger turbo, which has bigger exhaust and compressor housings which is why it makes more power.

I was just trying to ascertain what exactly the differences were other than the usual "it wont fit" response. It seems the exhaust manifold flange is larger and the turbos dimensions and orientation are slightly different, not insurmountable problems, but i guess the point is that most people either go for the bolt on -015 option or if they want more power they go for something larger like a GT28RS

 

[docurley]

the point is the K04-015 is basically a K03 with modifed larger internals, as you can see in the pics they are externally the same. The k04-02x is a larger turbo, which has bigger exhaust and compressor housings which is why it makes more power.

I was just trying to ascertain what exactly the differences were other than the usual "it wont fit" response. It seems the exhaust manifold flange is larger and the turbos dimensions and orientation are slightly different, not insurmountable problems, but i guess the point is that most people either go for the bolt on -015 option or if they want more power they go for something larger like a GT28RS

Or the Eliminator kits which use the stock manifold which as we all know becomes restrictive at a certain point although you can get bigger versions of the stock manifold but it defeats the point as you might as well by a full GT turbo at this point.