Is it a VF34 or a 35?

Any compressor maps please?

 

John,

Is the UK sti not a vf30, Jap Sti VF34 - which is a vf30 with roller bearings ilo slieve type.

A post a couple of weeks ago (in drivetrain) asking for vf30 power output got a link to a RHF55 compressor map, the chap reckoned they were one and same...looking at the peak flow however I was not so sure......

Do a search for vf30 to find the thread......

 

AFAIK both the UK and JDM STi7's run the VF30 turbo, the C type runs the VF34 (along with the S202).

Tony

 

I thought:

VF30 JDM STI7 Sleeve bearing
VF34 JDM RA TypeC Roller bearing
VF35 UK STI7 Sleeve bearing

Correct me if wrong.

But I can't find the compressor maps. Usual ****ing secrecy... how the hell are you supposed to map to make the most out of a turbo without the maps

I'll just have to make educated guesses based on wheel/housing sizes. Great

MRT says the VF34 is sleeve not roller bearing. Other info conflicts. Also I hear the VF35 has a P15 housing whereas the others have P18. Secrecy can go too far

[Edited by john banks - 1/11/2003 7:52:50 PM]

 

John,

have a quick drive up to Aberdeen tomorrow for lunch. There will likely be about 7 of the beasts there for you to examine!

Some might even be willing to let you have a tinker

John

 

Thanks John, don't have the software till next week, just planning what to do with the STis. The turbo efficiency is particularly important given that they are running on a TMIC, even if it is bigger.

 

John,

you will have "fun" with the boost control on the STi VII UK cars, certainly when they're fitted with a full exhaust system... it should become quite apparent to you when you get the software, why the UKs tend to boost spike. I've found that the UKs spool up really well, suggesting it's a roller bearing turbo. The JDM ones seem to spool a little later and a bit more progressively, but you do get to play with a higher redline I checked a JDM one and it is a VF30 turbo, I'll have to have a look at a UK one to confirm what's fitted.

Cheers,

Pat.

 

I am quite sure the EURO spec STi has a smaller exhaust housing compared to the VF30. This could explain the boost creep problems with the STi7. I mapped a MY00 with VF30 and with that one I had problems to achieve enough boost at high revs.

Mark.

 

As far as I know you are right John, the JDM has a sleeve bearing VF30, UK the roller bearing VF34 and some other european markets had the VF35 which uses a smaller exhaust housing.

 

This was discussed a couple of months back John but I'm afraid I've forgotten what was said. IIRC, Jamie Whitfield had a VF34 on his STi 7 Type UK (he had the Turbo off the car) and Dave T-S had a VF35 (also Type UK and read what was written the Turbo). Either that or Jamie had a VF30 and Dave a 34

This would imply that Subaru may have switched turbos mid production run (just to make it even more of a PITA!).

Matt

 

Just checked in the shed and the turbo that came off my car is a VF35.If you want I can get all the other numbers of it if it will help you.
Type UK Jan 2002.
Matt if your'e right about Jamies car why fit two different turbos to the same car,also do you fancy doing a comparison reading from the delta dash from my car against some of the others you have done.Let me know.

Grant

 

Thanks Grant/Matt. No evidence of any compressor maps anywhere sadly.

 

Hold on a minute Hohn. Didn't someone post a link to the IHI Site in the US the other week specifically for some compressor graphs for the STi turbos (or was that something else).....

I'll see if I can find it....

Matt

 

Matt,

Thats the one I followed....but the flow map suggested didnt look to support the the airflow the vf30 can deliver.....IHI RHF55 I think....

 

John,

There are some flow maps and stuff on here (I think you want the RHF55

This was the one I was thinking of....

Now you just need to figure out which turbo is the RHF55

Matt

 

What has the better, bigger turbo....the JDM or UK STi-7 ?

Cheers,
Ray

 

Is bigger always better? The VF30 might have a bigger exhaust housing, giving the JDM the edge?

 

LOL...well I don't have a clue which is why I asked the experts....all around wise, size, flow rate, speed of spool up, longlevity, bearing vs. other etc.....when comparing all these factors is the UK or JDM better ?



Cheers,
Ray

 

ah ha ! I have stumped the experts

 

Thanks Matt, been on those. RHF55 covers a wide range of turbos. Thanks anyway. Seems like the info is not public domain.

[Edited by john banks - 1/12/2003 8:21:16 PM]