Turbo spec

[prj]

Aha, no anti surge housing. (or MWE as Holset named it) Makes it more efficient flow-wise but more prone to surge at big throttle actuations.

There are no surge problems on a 2.2T with #6 housing and this turbo. Mapped two of them.

Strange way to balance an impeller, removing material from the front of the backplane.

Yes, I noticed this too. I was wondering if it could reduce efficiency.

What size is that impeller? 56/82?

Exducer is 78mm... So it's not the biggest wheel.

Reaching 475hp with that 6cm^2 hotside?

I don't think so. You can run about 1.6-1.7 bar to 7000 rpm on standard head and 7A cams, then the backpressure from the small #6 housing causes an impenetrable wall of detonation.

I'd say 430-450hp on pump gas. But this thing gives full boost only 100 RPM's later than a RS2 turbo, and makes 80 more horsepower.
Compare that to to a K26/K27, which spools 300 rpm later and makes 70 more, and it is apparent why this thing rocks.

This is very close to a GT3071R/0.63. It's less like an on-off switch, and 100rpm later full boost, but it does not run as hot to redline.

I like the fact that it can be rebuilt easily and cheaply. I would not want to fit a bigger hotside on this HX35 though, this is perfect for a car with stock rods.

[Jamo]

Ok what do you think about a gtx3076r turbo from 034 motosport ?

You can buy it in the UK via Owen Developments, AET turbo or Turbo dynamics.

I'm not a fan of the gtx3076r if you wanted 600 bhp go for the gtx3576r or the gtx3582r and leave the gtx3076r alone

[prj]

HTA3076R is good, but GTX3076R has turbine flow issues. You hit a det wall basically.
Maybe with a 1.06 housing it would be good, but it would probably be way too laggy for a 2.2T.
GTX3576R should do 600hp, and spool better than GT3582R.

[Billman]

Strange way to balance an impeller, removing material from the front of the backplane.

First time I see it done to Holsets....makes me think of non genuine but not sure.

How much do they charge for the housing to fit?

[prj]

First time I see it done to Holsets....makes me think of non genuine but not sure.

I don't follow your logic. What does the way it's balanced have to do with the parts being genuine or not?

[Billman]

Is the turbo not factory balanced? I thought the CHRA was bought together.

[prj]

Is the turbo not factory balanced? I thought the CHRA was bought together.

Uhm, no?
Not the case with my turbo anyway - the fact that it has a K26 hotside might have something to do with it, as it's not exactly plug and play.

[Billman]

Did you mapped any HX40 turbo with K26/6 housing?

[prj]

Did you mapped any HX40 turbo with K26/6 housing?

Why would you put a K26 #6 housing on a HX40?

Even with this 78mm comp wheel it barely heats the air at all...

[Billman]

because I have one laying around :-D

Nervas had one back then on a stroker engine. I would like to know If someone measured one on 2.2. I had this kombo on the old 2.2 engine (with 56/82mm compressor) but never was on a dyno.

http://www.s2forum.com/forum/showpos...29&postcount=1

How much do this Turbo shop you bought the turbos charge only for the turbine housing?

[quattro84]

I don't follow your logic. What does the way it's balanced have to do with the parts being genuine or not?

The Chinese use these kind of balancing methods...
Factory balancing is done on the backplane of the impeller, if not enough followed on the outer circumference of the impeller radius only! Turbine rotor gets balanced on the backplane as well and entire assembly (minor balancing compared to single component) achieved by grinding the nut at compressor and 12-sided "bolthead" of turbine rotor.

Grinding on the backplanes and outer radii are done by (C)NC machine, nuts by hand or automated deburring tool. Perhaps your local shop made these balancing scuffs, not ideal because location is not ideal to measured unbalance angle position. Don't think this makes a big influence on total efficiency, but Holset MFS wheels are coated so that makes it vulnarable to cavitation.

[prj]

How much do this Turbo shop you bought the turbos charge only for the turbine housing?

Sorry, but it is not in my interest to say my prices...
Also, I supplied the K26 #6 housings. It's pretty hard to find ones that are not cracked badly.
The turbo shop refurbed them, but they had strict guidelines, that if there is a deep crack towards the downpipe the housing can not be used.

Grinding on the backplanes and outer radii are done by (C)NC machine, nuts by hand or automated deburring tool. Perhaps your local shop made these balancing scuffs, not ideal because location is not ideal to measured unbalance angle position. Don't think this makes a big influence on total efficiency, but Holset MFS wheels are coated so that makes it vulnarable to cavitation.

I am sure the turbo shop made these cuts because they look fresher than the rest of the wheel if you look close.

I don't think they buy the whole CHRA...
Either way, it's a pretty known company, my contact is the director of the company through a mutual friend, I am not worried about the quality or origin of these

[Billman]

Sorry, but it is not in my interest to say my prices...

Sorry I thought you just happen to buy those for customers.

[prj]

Sorry I thought you just happen to buy those for customers.

Well, I was going to sell one on the forum, but before I could, I had someone in PM who needed a turbo...

The other 2 went to my friends. I actually have now only one left, from a friend who has not picked up his yet.

If I can find more K26 #6 housings without bad cracking, I can get more made up, but I want to first see how this batch of three performs and then go from there.
Even though I have already mapped 3 cars with the exact same turbos from the exact same shop and they ran perfect. And much better than K26/K27.

[pasbogdan]

Well, I was going to sell one on the forum, but before I could, I had someone in PM who needed a turbo...

The other 2 went to my friends. I actually have now only one left, from a friend who has not picked up his yet.

If I can find more K26 #6 housings without bad cracking, I can get more made up, but I want to first see how this batch of three performs and then go from there.
Even though I have already mapped 3 cars with the exact same turbos from the exact same shop and they ran perfect. And much better than K26/K27.

Can you please tell me what should be the rpm for peak boost(set at around 1.8 bar??) at these turbochargers in 3'rd gear lets say?

Thank you