legacycentral bbs

Ok. I have a interesting question. What would happen if you swaped in a VF39 in place of the VF11? Would the car explode? I mean this car is TOTALLY stock aside from a TBE. What would happen? I know the VF39 pushes more CFM's. I just dont know what would happen.

Aswell i have a VF39 in need of a rebuild i think. My VF39 makes a odd HHHHEEEE sound. Its not loud at all. The turbo dont have like much shaft play but it only makes that noise!

You would probably just hit fuel cut before the thing was even to its sweet spot.There is really no point in doing this.

So in a pinch if my old vf11 blew up i could stick in a vf39 and it would run but NOT nearly to its optimal performance. I do have many of things to make it run like: 550cc injectors, rails, Maf, soon to be AWIC. I just have been waiting for the guys at Revtronix to create the tuning chip for a vf39. Which has been while. But if there stage 2 chip is really nice ill definatly wait until they make a stage 3 with vf39 support.

but NOT nearly to its optimal performance

Indeed,just wait for all the goodies to come together....or sell me the turbo.really.

I wouldn't think you'd need much more than injectors, fuel pump, and EM. Although, an intercooler would help make a more powa!

beatersubi wrote:I wouldn't think you'd need much more than injectors, fuel pump, and EM. Although, an intercooler would help make a more powa!

That's quite a lot, in the end. That's what most of us shoot for short of cracking the engine open.

You should be able to get away with wastegate boost on it...


But this is ringing the "stupid idea" bell

LOL. Ok then. NOT a good idea. I just got word from Revtronix anyways that they are 98% done stage 2, and will be starting the stage 3 in around a months time! So im totally jacked up about that! I can finally use my VF39!!!!

In saying that im NOT going to install the turbo!

Aswell i have a VF39 in need of a rebuild i think. My VF39 makes a odd HHHHEEEE sound. Its not loud at all. The turbo dont have like much shaft play but it only makes that noise![/quote]


I thought vf-39's weren't rebuildable? Can anybody confirm this?

abest10 wrote: I thought vf-39's weren't rebuildable? Can anybody confirm this?

You're right. IHI turbos don't have rebuid kits available like the Mitsu turbos have. When one wears out, you need a new center section.

I sent mine into deadbolt turbos and they "rebuilt" it. No idea what they actually did, but works great now!

Also I am running my vf39 right now on stock injectors, stock EM, FMIC, at .9 bar and it runs nicely.

I'd like to see Revtronix make a Stage 3 chip for the VF39. I am running VF39 at 15psi on 440's, walbro, FCD, and the stock EJ22T ecu with no problems.

I'm going to call Revtronix sometime next week to get some info on their future plans on Stage 3.

I am running VF39 at 15psi on 440's, walbro, FCD, and the stock EJ22T ecu with no problems.

gijonas wrote:

I am running VF39 at 15psi on 440's, walbro, FCD, and the stock EJ22T ecu with no problems.

Curious as to how?

Since this is an OBD1 ecu, the ECU essentually "learns" to trim fuel the slightly larger 440cc injectors. Stock for this car is 370cc. This is a good mod for these cars because by adding a larger turbo, in this case a VF39, the higher airflow produced, even at stock boost levels creats higher CFMs which the larger injectors (i.e. more fuel at the same fuel pressue and injector pulse widths) support from a fuel standpoint. So the ECU compensates and lets the car idle correctly, yet run higher boost with safers AFR's.

I dyno'd my car at Surgline Tuning in Portland OR and AFR peaked at 12.2 at 5800rpm. Other than that, it remained at a close 11.5 through out powerband.

This is good to hear I'm about to drop a VF39 on my 91 SS too, I just
picked it up yesterday, and got my 90 degree elbow in the mail the day
before.

jton wrote:Curious as to how?
...
I dyno'd my car at Surgline Tuning in Portland OR and AFR peaked at 12.2 at 5800rpm. Other than that, it remained at a close 11.5 through out powerband.

Looked at your MAF voltage? I found that with my TD05 even at 11.5 PSI (no FCD installed), it was getting maxed out which then caused the 440cc injectors to go static and dump fuel. Clearly seen on my data logging thread with the flatlines. So while yes, it "works" and your AFRs are ok during WOT, it certainly isn't ideal or good in the long run for good power.

^My car has been running this set up for the past 4 years and hasn't had any issues.

I do believe the Hitachi is close to, if not, has seen max voltage. You are right about the MAF voltage and long run scenario. Of course, I drive my car conservatively due to it being my DD, so high rev WOT are mainly on the spirited drives.

It would be ideal to run an upgraded MAF and also have EM for fuel.

Just adding my input for those to reference to.

Cheers

I wired my AVCR boost controller to read the injector duty cycles the other day and saw a max of 92% at or near redline, at .9 bar, on my vf39 with FMIC.. Stock injectors. Since this is my DD I'm not hitting redline on a daily basis so I'm not worried. Plus I put money or trannys breaking before these motors do.

There's some good info here. I plan on upgrading the downpipe soon before the turbo. I was thinking too big with a 20g. A VF on moderate boost looks like a fine match considering my goals and mods.

What are a 39's real upper limits considering these heads?

Wow. i cant believe that is topic is still alive!

Hmmm Now im interesting in getting my turbo looked at for defects and stuff! Ill run her hard tho only when revtronix releases the stage 3 or custom tuner for the leggy. My final setup for the car's engine will be as follows:

VF39 ( rebuilt ) or sound in some way
550CC STi injectors (04 STi yellow tops)
New/Old 90's N/A Legacy fuel rails
Froozen Boost AWIC
JECS Maf ( 98 outback )
Walbro 255 fuel pump

And yes the Revtronix's ecu chip! Tiss the key to getting 250WHP
Aswell might sub out the VF39 if it cost too much to fix. Might in that case buy a TD05-16G.