Erik

Hi

I decided to spare this weekend in garage swapping OE turbo for VF23.
My car have new fuel filter, Denso IK22 sparks, K&N 57i kit with heat shield, STi02 IC bonnet vent, Scoobysport DP+BB and Dawes.
Running with 98RON only.
Can you tell me what is max boost level (I have not knock link at this time)?
ECU can read up to 1,25Bar, cut is at 1,15 but this is for OE turbo... I dont know if ECU have maps rich enough to compensate more airfow with biger turbo?

Thaks for advice

Erik

StickyMicky

hmm i run my 97 wrx @ about 1.34/5 ish bar with a dawse device but this tails off towards the redline

its a nice turbo, you will see massive gains on boost, when it comes in it really comes in hard and fast

well recomended, i changed mine over last weekend

my car doesnt knock if that helps and mines a bit more liable for a good det session then yours, although i add a dash of NF to mine

your ecu will adjust to the new turbo (mine has on all 3 turbos ive had fitted)

but a remap would be best 1.15 bar equals a lot more air in your new turbo then the old one

so 1.15bar on the vf23 equals more power then a 1.15 td04

NM

Get a remap from Power Engineering ! Otherwise something will soon go bang !

They will remap a UK98 ECU using their Phase 2 remap method.

I had my MY98 UK turbo remapped running a VF24, 440cc injectors and uprated fuel pump and regulator and got a safe 311BHP and 290Lbf @1.3bar peak.

Give Robert at Power Engineering a bell and tell him that Neal sent you from the Scoobynet Group Buy. Foe more info check out the old thread in the Group Buy section.

Cheers

Neal

Erik

Thanks for advice once again
I have it! 9 hours hard work so my advice is dont do it yourself if it iss your first turbo swap
Only changes I need to done were boring bigger holes on lower water cooling adapter and disconnecting two oil/water inlet rings at turbo side.
Iam driving with OE boost level seems to be pretty hard from 4500 to redline. What supprized me is smooter atmo mode around 2000 rpm. Boost come up from 2700rpm but till 3500 is only decorative
Turbo have funny sound at IDLE like yowling (meow) and when I drive hard exhaust sound is louder than old TD...

PE is good, only 1000mls from my home and turbo cost me 210GBP only so I plan cheap and reliable upgrade only.

StickyMicky

intresting that you have a downpipe
is it a open neck design?
my gives the full surge from 3500 and i dont have a decat downpipe fitted yet, i always thought the decat dropped the spool point a bit lower?

Erik

Yes from Scoobysport.
First kick back is from rpm as you say and secont mode stronger is from cca. 4500rpm.
May be is is it due my mid cat?

Scott.T

iTrader: (2)

I am also thinking of changing my TD04 toa VF (of sorts). Can you enlighten me more on the modifications you had to do, as I was under the impression they were a straight swap.

StickyMicky

well mine originaly had a vf22 as standerd so all i did was go from a vf22 to a td04 for a few months and then back to a vf23

mods, i had none, apart from a dawse device, but my car struggled to control the boost as standerd so it was fitted more to sort that out

on the rollers it was boosting far to hard and fast and then dropping it and then picking back up again, so a dawse was added to smooth it out, which it did.

Erik

So at first I hope that all holes are the same. Otherwise my turbo is 3days long water lubricated
VF23 have practicaly same holes for water cooling and luvrication. Hole on the top is stright swap. On the side are two holes. Distance between holes is a little bit higher than TD and connection pipes have two ring/hollow screw this rings are welded togheter and you need separate it.
On VF underside is same place for small water cooling adapter but if you try put it down from TD you will destroy the gasket. Screw holes on adapter need to bored bored for 2mm bigger holes to fit it on VF and instead old gasked you can use water and up to 120°C resistant adhesive/glue.
All other gaskets on exhaust in and out could be carefully removed with WD40 help.
Hardest part is replacing VF to the car. Downpipe down, Upipe down, pulling back turbo inlet... great work you will enjoy it
After 3 days car still run, i feel it much stronger and louder.

StickyMicky

did you not get the bolt on connections with the turbo?

Erik

No turbo was from my friends STi MY97. Turbo + one screw only.

greasemonkey

Don't you think that's something you should pay attention to?

If your new turbo is producing more boost at the top end of the rev range, it may be running both too little fuel and/or too much advance.

If your aim is for a cheap and reliable upgrade, you would do well to get some sort of knock and airfuel ratio monitoring at the very least.

Erik

Iam afraid in cylinder cooling for. More fuel with OE turbo works like additional cooling. Iam using that +fuel for performance and cooling may be insufficient and I can overheat sparks and valves nad car can start knocking.
AFR with narrow band lambda sensor is not accurate. You need wideband like Motec PLM to see if you are really lean or reach enough and this toy is pretty high-priced.
My friend have it and knock link too, I will check it soon, I run at 0,9bar now.

Does anybody know how ECU works?
MAF sense air mass...
MAP can see boost...
Knock is adjusted by ECU "on the fly"...
If Iam right and ECU have maps up to 1,25bar it can adjust itself for new conditions if boost level stay between max MAF level. Knocking is solved with 98octane and much cooler air due bigger turbo and ECU knock retard mechanism.
If ECU is unable put the right amount fuel becouse does not have maps for higher air amount at present boost level Iam asking for big troubles...
I dont have fuel cut riser and boost should never rise over 1bar.

dowser

Erik - you're right regarding the MAF based stuff. Any additional airflow is picked up by the MAF and the ECU makes it's timing and fuelling decisions based on a load parameter which is *mostly* based on MAF input (also seems to monitor TPS and MAP too, but hard to be definitive......).

The problem you have is that the load scale on stock ECU's doesn't go high enough. This means you will be running timing and fuelling based on a lower load value. It will depend on your supporting mods how much of an issue this becomes Also note: a my98 has 380cc injectors.

My experience with VF23's is never run them over 1.35 bar (on track at least - I broke a compressor blade on mine first time I ran it on track at 1.4 bar). I actually don't like VF turbo's - nowhere near as capable or robust as a td05, and when something breaks it's a core only job (everything is available for a td05!).

A cheaper wideband solution is available at www.techedge.com.au. For sure you should invest in a knocklink and cross reference it's output to a set of det cans if you intend pushing things too hard at high revs (1 bar at the redline with a vf23 will probably be maxing out 380 injectors [which is not *necessarily* a bad thing on the stock map.....but is why you should have a knocklink ]).

Richard

Erik

Yes I have 380 injectors only. Changing injectors for bigger one without remap is stupid idea.Thats why I dont go over 1bar.
OK I make a place for knocklink in my car ( oh it is so ugly ).

My friend have new mapped 2,5 convesion with 20G TD based turbo Iam awating repport and first imressions.
VF is cool, much more torque and exhaust, bov tuned WRX STi is slower now...

Erik

Another question. What is it?
At IDLE I can allways hear that turbo. It is like squeaking. Works well no big lag, easy run on full boost and when I turn off engine it takes 2-3s long before squeaking gone. No oil leaking...
Is it due roller bearing?

greasemonkey

The roller bearing turbos have lower rolling resistance than the plain bearing ones and it's not abnormal to hear them spinning at idle, and certainly normal to hear them spinning down after the engine is killed.

However, "squeaking"? If everything's right the sound at idle should be a continuous quiet whine. If it literally is squeaking, it sounds more like the bearings worn/chattering than anything else, which isn't good...

Erik

Ill make audiosamle on this weekend and make link here. It is continous sound.