sti_mike004

iTrader: (1)

I'm thinking18g is better over all quick spool and better top end. 04 wrx Sti is what I have. Any input about the turbos or you personal experience would help about the two. Thanks

mistaanime

iTrader: (12)

yea if you got to choose over 18g or vf39... for sure the 18g. I think your sti comes with a vf39 tho. anyway.. the vf39 is notorious for it's hair line crack on the housing.

I've owned the vf39 first and then i cracked it, i lost pressure so i siwtched over to a vf34.

sti_mike004

iTrader: (1)

I lost pressure aswell. And oil in my intercooler alittle smoke to. So its time for a upgrade.

ds baruuuuu

iTrader: (16)

for an sti id do nothing less then a 20g

4080wrx

iTrader: (38)

This^^

From what I've experience and seen. A vf39 will yield u insane Tq numbers where as the 18g will give you the higher HP number. Coming from both turbos I would have gone bigger ie 20g or a green or something along those specs. 18g is a waste IMO on a ej257.

PRNDWRX

iTrader: (5)

20g on the sti! It is not that much more expensive and will suit the sti better. Forced Performance is also having a great sale on the FP red right now (down to 699) but it will be probably bigger than you need.

Island Style

iTrader: (66)

Just remember, with a bigger turbo comes the $$$ associated it... supporting mods...just some prices I've seen used/new off the top of my head...you could plan and save yourself a lot of money by buying good, used equipment.

Assuming you already have: Up/Downpipe/Catback/Intake like most people.

Minimally:
Fuel Pump ($150)
Injectors ($400-$600) used/new
Bigger topmount or front mount intercooler ($400-$1300)

Other mods that will help make power and decrease spool time...
Electronic Boost Controller ($150)
EL/UEL Header ($200-$1200)

And don't forget...
Tune ($420-$600)

Of course, you could go all out...but the above lists the most common upgrades people do with a bigger turbo...

Comes down to what you want to do and how deep your pockets are.
I was totally happy with my FP 18g on my 04 STI...no lag to speak of and great 0-60 acceleration...it was a lot of fun. On the other hand, I saw Chasen recently make 371hp/37xtq with a TD06h-20G (06 STI) at the latest PDX Tune Day with Jarrad...crazy numbers! He had all the supporting mods and 50/50 Meth...but still...awesome.

Just wanted to chime in to show you what you could be getting into with a bigger turbo...modding is an addiction...once you start, it's hard to stop...

silverbullet415

iTrader: (12)

i had a 18g on my old car and it was great

SUMATIC808

Yes i made 371whp/376wtq with my 20g, spool is amazing, almost like my stock turbo stg 2+ setup. without meth you could still make a good amount of power. Considering how conservative you want to be and what kind of supporting mods you invest in. Id say the 20g was well worth it for me.

YuudaiSTI

iTrader: (11)

I have an 18g on my STi. Spool is quick-ish, but it falls flat on it's face in the top end, kinda how the vf39 does. Good enough for autox though (which is what I had it tuned for)