How much power could you extract from a standard VF23 with the right mods?

 

I have one of these (V3 Sti) and apparently "The VF23 starts the middle ground. It comes on boost around 3100 rpm and is capable of running 20 psi of boost. Expect to max out the VF23 somewhere in the 300-350 hp range"

source http://www.scoobytuner.com/tuning/?tSfID1=4&tuningID=43

I can to some extent verify this having run 298 bhp at 1.3 bar a year or so back with a completely standard set up (bar panel filter)...

 

with supporting mods such as filter, full exhaust including de-cat, larger injectors, uprated fuel pump, boost controller, air/fuel controller and a front mount intercooler could i achieve 330bhp to 350 bhp? how much difference could i expect from adding a apexi power fc to the above?

 

iam running 27psi on mine and ill be around 340bhp 370torque on a 2.2ltr but ive got a lot more bits and bobs on there,putting a td05/6 on next

 

how many miles have you ran it @ 27psi?

i fried one trying to run 1.45 bar midrange (about 21psi)
i run my current one @ 1.37/8bar midrange which is the max rated safe power for the turbo (according to the flow charts i got from john)

i belive mine should be about 330bhp and 300lbft

 

This is almost exactly the set up on my MY98 plus I also have GruppeS headers. The Power FC was set up by AndyF and I got 305bhp/285lb ft at Dastek. That is a bit less than I was hoping for but the car is very driveable. However, power shortage must be addressed so I'm looking to change the turbo next year, probably to one of Andy's specials

 

i take some of that back, i peak at 27psi then it drops to 22/23psi and holds(if its not to hotter day)if its a hot day then it drops to 17/18psi

but ive been running that for 15 months about 11k

 

how can it hold 22/23 psi at the redline?

 

it is m8, only on the cold days,at the scooby shoot out i used 10 ltrs of water to keep it cool lol,at the scooby shoot out it was holding 18/19psi with it being so dam hot,got to give and take a little with the gauge if you now wot i mean so 27 could be more like 25/26.


simon

 

You've got a strong one then, I've heard of a few exploding at 20 PSI.

I would, and have happily had TD series turbos boosting to 25-27 PSI, but a VF Even my hybrid blew up when given 22 PSI.

 

I got mine mapped to 1.3bar (19 PSI) as I'd heard they were unreliable above 1.4bar (20 PSI).

Dave.

 

john and it takes my anti lag as well just had the down pipe off on sunday and theres no play in there at all

 

what would be the best front mount intercooler to go for? something like a HKS or universal one with a core size of about 600mm?

 

mine was fine until i whacked it up past 20 psi for a late nite duel

i forgot to turn it down the next day and it went pop

 

what turbos would be a bolt on replacement for a vf23 capable of producing 400bhp?

 

Dave, you heard right then In my early days of tuning we had an unlimited cheap supply of VF23's - we just assumed it was normal for compressor wheels to fail if you went above 1.4 bar.

Then I fitted a td05 and realised the VF23 was just a weak piece of crud. I believe the VF22 was, if anything, even weaker on the compressor side. To the VF series credit, the vf34 is very nice and we've not broken one yet

Worth noting that a failed VF23 (compressor wheel broken, but bearing still OK) is a very nice candidate for a KKK RS2 compressor wheel. Not much machining required to fit, doesn't fail anymore (not run it past 1.45 bar though) and better power output (doesn't spool quite as early).

 

td05/6 the 1 andyf does

 

Richard,

So I've done at least one thing right then cool

I didn't want to push it as its always been a bit noisy (when you switch off the engine you can hear it slow down).

Dave.

 

where do you get this wheel from and what needs machined?
approx extra power output?

 

Dave - you need to really worry when you hear it as it's spooling, means a broken blade!

Sticky - not sure, KKK are the manufacturer of the turbo, can check with the builder if you're interested. Compressor cover needs machining. Car was running stock fuel pressure/injectors, so was limited to around 1.1 bar at the redline. Major difference was the mid-range, was a while ago and don't want to guess figures.

Richard

 

Richard,

Cheers for the advice, not too worried at the moment as its been like that since I bought the car (16k miles ago). I'll source a replacement early next year anyway, don't really want to be looking for bits of turbo blade in the intercooler etc..

Dave.