Hello Gents:

Greetings and salutations from the Great White North. Which you will know as Canada. I am very pleased to join your fraternity (or sorority). I own a 2005 Saab 9-2x Aero which you will recognize as a 2004 Imprezza WRX. It is the wagon version. I have a question that I am sure you have answered many times before. I have many mods planned for my little auto and would like to know what turbo to fit to it. I have an opportunity to purchase a used VF23 for a reasonable price. I am looking for faster spool up than the stock TD04. Is this turbo a good choice? Could you suggest a better one?

Thanks,
Rick

 

Welcome. Would suggest you will find it hard to beat the spool of the td04. Are you after higher power of just better spool. A well mapped vf23 will be on a par with the td04 for spool with higher top end. However I would suggest looking for a hybrid td04 for improved spool. Paul

 

Hello Paul:
Thanks for your reply. I suppose I am looking for both, quick spool and more power in the way of torque. Unfortunately we are dealing with physics here and larger boost pressure require larger turbines and larger turbines have more mass and consquently larger inertia to be overcome.

I am going to add these mods to my car.

-Cobb downpipe already ceramic coated (one high flow catalytic converter)
-Grimmspeed ported exhaust manifolds, crossover pipe and uppipe all without catalytic converters which will also be ceramic coated.
-Cobb Accessport engine management unit
-3 port electronic boost control
-uprated fuel injectors and an upgraded fuel pump to supply demand.

From what I have read so far the TD04 does indeed spool up faster than most, but runs out of breath long before other turbos such the VF23 and VF30. There seems to be a controversy over which of these is best. Can you give me any insights? What I understand so far is the VFR23 is best at mid range torque with the VF30 producing the most HP. What I am a little concerned about is that it is said that the VF23 runs quite a bit hotter which may cause intercooler concerns. There is also a lot of discussion concering the longevity and reliability of the VF23's ceramic roller bearings versus the VF30 bronze bushes. Any help in aiding me in choosing would be very much appreciated.

What is a hybrid TD04, I have not heard of them on this side of the pond?

Thanks,
Rick

 

check out http://www.andyforrestperformance.co.uk/ for info regarding the td04 hybrid

similar spool but more top end

 

Thanks so much, sounds like what I have been looking for. I have sent an e-mail to enquire about shipping to Canada.

Rick

 

VF34 working very well on 2.0L WRX,i've on mine and i've made 350bhp with supporting mods(decatted exhaust,Decatted up pipe,OS Tune,STi pink injectors,FMIC),really nice spooly turbo on WRX.

TD04 Hybrid will make around 310-320bhp at the top


Jura

 

nice to here from people over the pond, good luck, enjoy your scooby!!

 

I doubt you will improve the spool on a TD04 from changing the turbo and still retaining the ability to make 280-300 bhp if you have all supporting mods.
Properly porting your headers and a matched uppipe will help spool and responsiveness and add torque but if you change to a bigger turbo or any alternative I know you are going to lose some of the spool.
What would really improve your spool would be a dose of nitrous but that is rather extreme and not really practical for a daily driver.