Dannymot

As above I'm taking the car to chevron to have the b14 bilstiens fitted and a few other jobs and having the ecu changed for the alcatek unit.
I wondered if I maybe worth changing the injectors prior to going aiming for around 350 bhp ideally . Will std injectors make this power safely?

joz8968

iTrader: (13)

1997 is the revised 'phase 1.5' MASTER engine with centralised coilpack/HT leads, and the STi variants got 440cc jobs. Think the engine designation is EJ20K. They flow enough for about 325-340 flywheel bhp (at std 3-bar fuel pressure).

Dannymot

That's great info thanks !! so a bigger set of injectors and an adjustable fpr would be a shout then .

joz8968

iTrader: (13)

Your car is supposed to have a 'medium sized' VF23 as std, which can do upto 350, I think. Thing is the v3/4 cars were a bit all over the place, equipment wise. It could actually have the smaller VF24. Also, I think there was the option of the large VF22 too.

You can find out by checking the turbo compressor cover - the info will be embossed in it.

But yeah, moving to 550cc's would make sure you're not left high and dry (literally).

I assume you've got a FMIC on already?

ossett2k2

iTrader: (9)

If you're only aiming for 350bhp It's either bigger injectors 550's or an aftermarket fpr. You don't need both.
I personally would go 740cc incase you want more power in the future.

ossett2k2

iTrader: (9)

My v3 had vf22 as standard,capable of 350-380 max boost of 1.4bar safe

joz8968

iTrader: (13)

EDIT: misleading (read, wrong lol) info.

banny sti

iTrader: (68)

Always believed that the sti 3 came with the vf23, the my97 wrx with the vf22 and the sti 4 with the vf24

joz8968

iTrader: (13)

It's in that list somewhere. I'll dig it out...

joz8968

iTrader: (13)

IHI VF22
(490cfm at 18.0psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM V3 Subaru Impreza WRX and optional on the JDM Subaru Impreza WRX STi 22b. Of all the IHI models, the VF22 has the largest potential for peak horsepower, and is capable of supporting the highest boost levels. It is capable of running up to 25 psi. The VF22 is a roller bearing turbo that utilizes the P20 exhaust housing.
Expect to achieve full boost with the proper mods and a quality tune between 3200-3700rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.


IHI VF23
(388cfm at 18psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM Subaru Impreza WRX STi 22b. The VF23 is a ball bearing turbocharger that utilizes the P20 exhaust housing like the VF22. This housing is mated with the smaller compressor housing of the VF24 for fast response and excellent low and mid-range performance. It does not have the same top end power of the VF22, but spools up slightly quicker.
Expect to achieve full boost with the proper mods and a quality tune between 2800-3300rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.


IHI VF24
(425cfm at 18psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM V4 Subaru Impreza WRX STi. This turbo shares its compressor housing with the VF23, however, this housing is mated with a smaller (P18) exhaust side. The smaller characteristics of this turbo allow it to provide ample bottom end power and quick spool. This turbo is very popular for Imprezas with automatic transmissions and Group-N rally cars.
Expect to achieve full boost with the proper mods and a quality tune between 2800-3300rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

joz8968

iTrader: (13)

Banny was correct.

And I was originally correct in post #4 as regards the VF23/STi 3 marriage -- assuming, that is, it was std on ALL v3 STi (saloons), and not just the 22B?

ossett2k2

iTrader: (9)

Apologies,was indeed as joz and banny say,it was my old my97 wrx typeRA which had the VF22
My current v3sti has an aftermarket SC42ts so wasn't sure what was on before as standard,seems it was VF23 as said above,I stand corrected,soz

joz8968

iTrader: (13)

Thing is, as I mentioned, in reality, re. the MY97/98 cars, I think Subaru/STi just bunged on whatever was lying around in their parts bin!

Although that in itself could be urban myth (wouldn't be the first time lol).

Dannymot

I will have a look at mine tomorrow it's in a storage garage at the moment . Although I've also been thinking of going twinscroll with it . Do the twin scroll units still have a good peak horsepower like the vf22?

joz8968

iTrader: (13)

VF36 should do 360 easily.

Or there's the VF47 and the 49 - good for 370?

Or there are aftermarket options from Scooby Clinic.

Dannymot

vf24 is whats on mine. so maybe well worth upgrading. With yellow sidefeeds on.