I am thinking of replacing my VF28 on my STI5 as its now nearly done 100k and i fancy a bit more power.
Im currently running a full decat, new age TMIC, ported headers and standard 440 inj.
She was recently mapped by JGM and dynoed at 300 bhp and similar torque.
Im looking for 340 bhp (no more as i dont want to compromise the G/box)
I do like the quick spool up of the vf28 so would be looking for something with similar characteristics.
Of course i want to do this as cheaply as poss.
What would you suggest
Cheers
Chris

 

VF35 quickest spooling turbo after the td04/hybrid, capable of 340 with the right mods, 330 common.

David at APi seels em, give him a call and tell him Ns04 sent ya
Ns04

 

ive been told the VF35 moves about the same CFM as my VF28

might be an idea to have a chat David - cheers

 

the VF28 will get 330 with the right mods, was yours ported? it made a difference to mine.

 

nope wasnt ported came as standard - however i do have a spare vf28 siting in the garage i suppose i could send it away and get that modded and ported.

i forgot to mention walbro pump on car as well

 

hey mate mine was dynoed 298bhp with just cat back kakimoto s/s 3" exhaust on vf23 (very similar, but a bit bigger than vf28), i'm going to fit hydra ecu, fuel pump and remap, all with oe tmic, going for around 330bhp/330lbf

 

VF23 has nearly the same compressor as the VF28 but with a p20 hotside for more topend power. This is at the expense of the spool that the p18, fitted to the VF28, offers.

VF35 has a p15 exhaust housing for quick spool but has a larger compressor housing that should provide more power than the VF28 or VF23.

 

I went from a VF28 to a VF34, very happy with it.

 

surely a vf23 or 28 would be capable of 340bhp ???

 

None of the above mentioned turbos are going to give enough power difference to warrant the cost. VF for VF will change spool a bit, but basically they are all the same. Anything prior to VF28 will have fragile blades on the turbines after all these years, unless brand new, which means that the risk of failure on a used one is quite high.

A real upgrade would be TD05 /18G.

The 440 injectors limit you to about 330 hp, sometimes a bit more, but at about that area on standard fuel pressure they are maxxed out.

Fitting a fuel pressure regulator and a Walbro pump will up the amount of fuel available to the injectors then they will flow more fuel and allow a possibility of 360 hp with a bit of luck. No need to go from one VF to another for that.

A remap is necessary of course, with either Ecutek [ Tek3 ] or a replacement ECU like Simtek [ removes the need for a maf which is a major source of worry on any 99/00 car ]

David APi