This is an an STi version IV so it's either a VF23 or a VF24. I'm wondering if anyone can identify it based only on a photo.

-Michael

 

Michael,

I've not seen a VF23 on an STi4, but the best way to tell, is to see what it says on the "info" plate, on the compressor housing.

You can't see it in the picture.

Mark.

 

I haven't been able to look at it closely in person but I'm told there is no plate with info on the compressor housing. If you've never seen a VF23 on an STi IV does that mean they were all VF24? It is apparently much smaller than the VF23 but I wouldn't know one if I dropped it on my foot.

-Michael

 

I have a vf24 sat on the table in front of me right now and it looks exactly the same as the one in your photo(which proves nothing), it has a name plate on the front of the compressor housing which says vf24!
I can email some pics if you like?

 

please do: michael@fastmail.ca

-Michael

 

Just taking them now.I hope the batteries don't go flat

Andy

 

Did you get them?

 

I thought the VF24/28 was only on the later models, ie STi V and STi VI. I always thought that there was either a VF23 or VF22 on the earlier models...

Brett

 

Dunno. There isn't really any knowledge in North America about such things.

-Michael

 

Looks like a garrett to me.

Claw.

 

Brett,

as far as I'm aware VF28 was fitted to V/VI and VF24 to IV

 

The only diference betwing the VF24 and VF23 is the exhaust housing
actually the looks the same, the difference is in the A/R.

 

Ok, finally got confirmation back. VF24
I guess in time I'll replace this unit with something larger.

-Michael

 

Dont change it - you'll get lots more lag and the car feels a lot slower - unless, you intend to do a lot of track day sessions when a bigger turbo comes in useful

If you must
Do not buy a basic VF22 - it will last a few thousand miles only and then the bearing will go!

 

Isn't the VF24 really limited when it comes to boost? Perhaps in a year or so I'll be putting in a GEMS and FMIC to crank about 20 PSI. This is only a long term plan that's still in the early stages.

Since I haven't even driven the car yet I'm still educating myself. Hell, I may drive the car and decide it's all the power I ever wanted. I have found in the past that horsepower is like money or sex; the more you get the more you want Probably after 6 months I'll be looking for more power.

-Michael

 

I'm fully expecting this one to have 300hp in stock form. That's 20hp gain on the MRT TB exhaust. Since it's an STi engine it redlines at 8250. Peak hp is at 6000 RPM. I assume the turbo runs out of air after that. Only way to tell will be when I actually start driving it.

-Michael

 

I have an uprated turbo (had a VF28, very similar to VF24) on my Sti V. I now have a lot more ability to hold high boost, and I can get 0.6bar at 2,500rpm and 1.0bar at 3,000 rpm - so lag is NOT an issue with a well sorted bigger turbo - BTW it is a VF23 (although it says VF22 on the housing!) hybrid with a special compressor.

The big difference comes with the type of downpipe. Also, with a VF24 running 1.5bar it will produce a fairly high charge temp as it will be going to the limit (and beyond) of the compressor map.

Trout

 

I agree with the charge temps, I've got a few niglets with noise in high gears on prolonged WOT runs....time for that FMIC maybe?

I'll try to see if perfecting the map can help things (bit short for chash right now) - otherwise I'll just have to bite the bullet and get that FMIC.



/J

 

* sigh *
If only Canada had switched to metric 10 years earlier I wouldn't be so messed with my measures. Here a Bar everwhere a Bar. I can't wait to see how many bar this thing runs stock. I've heard figured from 1bar-1.2bar (15PSI to 17PSI). I suppose I should be happy with the 120hp over stock that I have and enjoy it for a year or so.

Is there any realistic way to gain a decent amount of power without cranking boost up?

 

I dunno about limited....I am currently running 1.3 bar in the midrange on my VF24, tailing off to 1.1 at 7000 rpm.

IMHO there won't be a problem running 1.5 in the midrange....and you really wouldn't want more than 1.1-1.2 up high - if you aren't going all the way with internals...fuelling...closed deck...

It managed a steady 1.2 up on top though.

There's really no need for a laggy 450 break turbo if you're aiming for around 300 real ones.

/J

[Edited by SecretAgentMan - 2/8/2002 7:35:52 PM]