ScoobyWhite

I am thinking in upgrade my turbo (TD04) for a VF24 or a VF23.
I think that no body where have a VF24 so I would like to know what do you think of the VF23.
Power, spool up, lag, reability, etc.

Thank you.

nom

VF23 is a good 'off the shelf' choice. Spool-up would be higher, but more boost (at a lower intake charge) would be available over the TD04. There would also be an increase in lag. Pretty good reliability - not as tough as the TDI you have, but not one with any 'issues' either.
Depending on the price you can get one at, you may be better off with a hybrid that would be more likely to suit you needs. They are not necessarily much more expensive than an 'off the shelf' unit

chrisp

A VF23 (STI3) will be more laggy than a VF24,28,29 (STI4/5/6) but better if you want to get bigger power and run more boost form what I have read . You could go down the hybrid route as well

SecretAgentMan

I've tried both on a MY00, the VF24 with the stock TMIC, and the VF23 with an HKS FMIC (and a 4-1 header).

It all depends on what you're expecting from it.

If you want midrange go for the 24, otherwise the 23.

They share the same compressor housing, the VF23 uses the same exhaust side (P20) as the bigger 22, while the smaller 24/28/29 and 30 (iirc) uses the smaller P18.

I noticed that I could run my engine quite alot "hotter" (in terms of boost and advance) with the larger 23...

A hybrid is the ultimate solution - but at a price, and if you're aiming for ~300 hp, I'd recommend either a td04 hybrid (as per John Banks / Mark Aigin TD spec), or a 24/23.

If you want more - go hybrid IHI.

/J

WREXY

I bought a VF23 which will be fitted next Wednesday. I will let you know what I think of it towards the end of the month, when I get the car remapped with a Tek 3 off JB.

Cheers,

Wrexy.

MurrayZA

Running a VF23 and full decat on my MY01 @15 PSI. Goes
great guns. Full boost @ as early as 3500 rpm - depending
on conditions and gear selected. The extra lag does take
some getting used to though. I would like to try a VF24'd
car to see the diffs.

ScoobyWhite

Thank you very much for your answers , but let me ask you some more things.

I will mount it whit a FMIC.

To Secret Agent Man what do you think of the VF24 whit a FMIC. I would like to have more or less the same lag that I have whit the TD04. What do you call mid-range (3000rpm to 6000rpm. At what rpm the VF24 starts to tail off??

To all I want to ask you, what do you think. I will no go for more then 1.1bar - 1.15bar. I would like to have the same lag that whit my TD04. I would like to have really good mid-range and improved top end.
What do you think???
The diferences of the TD04 and VF24 are big???
What is the max. boost that the VF24 (I read that it can do around 1.2bar at 7000rpm, and what about 5000rpm what it can do??

Best regards and thank you.

john banks

The VF24/28 will definitely be laggier than a TD04L no doubt about it. It should come in just over 3000 RPM with a good push to the red line. The turbo could push 1.3 bar quite happily through the midrange. You could run more but it would make more heat and the exhaust back pressure would increase. In warmer conditions, depending on how good the intercooling is you might want to run less than 1.3 bar. There is no free lunch in terms of getting better top end airlow and having the same lag. A hybrid can seem like a wonder, but you still get more lag if you want significant extra airflow and you will never get a VF turbo to spool like a TD04 - for example 1.3 bar at 2500 RPM with no surge which is just possible on a TD04. Just use the gearbox more and fit a bigger turbo.

JIM THEO

ScoobyWhite I'll let you know about my car as I am going to fit a VF29 (basically the same as VF24-28) with Magnex downpipe, PE exhaust manifold and hope I'll have a good low to mid torque curve.
JIM

PS:John am I wright (det/heat) if I change the same time my plugs with PFR7B - 0,7mm gap or better to keep the original PFR6B?

chrisp

My VF29 starts to push at 2,500 but I suppose the RA low gearing helps in the midrange. It does seems to hold about 1.2bar easily but I havent seen anything higher. My Defi alert is set just over 1.2bar I hve havent heard it and the peak play back shows 1.2

I guess I may get a tad more when the cold weather comes.

Strangely it doesnt feel as laggy as my UK 98 with a TD04. My UK needed 3000+rpm to start moving.

It is very deceptive though as the RA is much quicker than my UK as it has more power and closer ratios and about the same weight.

john banks

Jim yes PFR7B 0,7mm.

SecretAgentMan

I never got around to try the stock td04 with the fmic, I have been in a friends car with that setup though, and it didn't feel like spool up had changed much from a regular tmic setup.

The 24 with the fmic worked very well, and I got 1,3 bar around 3400 with that and started dropping off around 5500-6000 rpm.

The 23 flows a bit better on the exhaust side, which makes it a better choice if you want to go for more boost.



/J

ScoobyWhite

No what I only want is 1.15bar (hold).
So the TD04 is about the same as the VF24 (size, flow, etc???)

So you are telling me that whit this Setup (FMIC and only 1.15bar) the VF24 is the best??

And what about the TD05 (somebody tell me that exists to versions??) vs the VF24.

Whit the same setup what do you think is the best turbo.

Once again best Regards.

john banks

The VF24 is much bigger than a TD04L. There is no free lunch and no "best" choice, but if you want a meaningful increase in power with more but not excessive lag a VF24/28/29 is a nice choice.

MurrayZA

Speaking of Lag, I had my car on a RR on the weekend.
Over here, on these rollers (all figures for my car):

Standard car: 105kw and 212nm.
PPP car (1.15 bar): 115kw and 222nm.
PPP VF23 (1.05 bar), full decat, restrictor altered boost: 139kw and 245nm.

Only "problem" is that now I have to wait an extra 500rpm for "action". Full boost and torque is there from 3600 or so.

How can I get this down a few hundred ?

john banks

A boost controller or ECU will make the most difference. The PPP duty cycles are totally wrong for a big turbo.

I am on the TD04L for a few days at the moment whilst leak hunting and the lack of lag (i.e. hardly any time from snapping throttle open to full boost) and the amount of bottom end is amazing. Shame that after 3000 RPM and especially after 4500 RPM it is a wet paper bag.

MurrayZA

Used a Dawes this weekend on the RR too. Had it at 1.2 bar and
over and above the figures quoted in my last mail, I got 150kw
and 275Nm atw. But at the same boost (1.05) as the previous run,
and on the road, the car didnt feel much different, BC vs no BC.
No BC is just safer.

hackish

I've got an STi IV with a VF24. I've driven a VF22 and VF23 car as well as one with the little tiny hairdryer of a turbo the USDM WRX gets. The VF22 was absolutely disappointing. There was absolutely nothing before 4000 RPM and it made the car very unresponsive for city driving. The VF23 was a little better and it seemed to hold boost a bit better well.

The USDM WRX turbo is just way too small for anything serious. It spools really quick but is severly lacking on being able to make a good amount of boost and it tails off pretty badly at the higher RPMs.

My VF24 is one that I'd recommend. It's got a liveable amount of lag but it makes full boost of a little more than 1bar (15.5PSI) at about 3100 RPM. By 3200 RPM it is making (about 1.3 bar) 19PSI which is where I have mine set on colder days.

The turbo holds boost pretty good up to about 7000 RPM. After that it starts petering off and sags about 4-5PSI at 8000 RPM.

-Michael

ScoobyWhite

And what is the best?????

VF 24
VF 28
VF 29

Regards

JIM THEO

The newer is the VF29 which produced only for Japanese domestic market. It's also cheaper than a VF24/28 while - according to Diesel Distributors that sell all of them - is a little bit better in terms of spool up. Although I haven't ever tried a 24/28. Look at MRT site the pdf files, there are some technical specifications about them.
JIM

madou

MRT pdf cited above

http://www.mrtrally.com.au/performan...turbo-data.pdf