driveeminpushemout

iTrader: (4)

I had my V3 sti mapped by jgm on 23rd may at surrey rolling road. It felt much better afterwards and took it to a track day the next day. It drove perfectly all day until I let my mate drive in the last session, He did one lap waming up, gave it boost twice and the turbo shat itself!

It's a standard vf23 and seemed to be in perfect condition when I checked it the day before mapping when I was doing the parallel rail conversion. It was running 1.3 bar of boost on a standart sti top mount.

Basically the shaft's bent and broken half of the compressor turbine blades. Is this because it couldn't take the boost, of just a faulty turbo? (no oil or play prior to this) I found bits of turbo in the intercooler, and swarf on the back of the throttle butterfly, so removed the inlet to found tiny bits on the back of the valves, so pulled the engine out and removed the heads to check the bores, but they're fine

I'm wondering whether to build it back up, or to upgrade the turbo to, say a vf35 and change the intercooler to a sti 8 topmount or a frontmount. I don't really want to use that intercooler again, even though I've cleaned it as best I can I'm scared of my bores!

Anyway, I'll list my current engine spec so any suggestions would be welcome as to whether it's worth upgrading or if I'll be at the limit of my other bits anyway, plus I only want to pay for another remap if I have to as I only got to enjoy the last one for a day!

My current engine spec is:

Standard sti v3 engine with standard headers and up pipe,
VF23 with standard sti top mount
440 injectors with parallel rails and aeromotive adjustable pressure regulator
H&S decat 3" downpipe tapering down to 2.75" at the end and a H&S 2.75" system
Standard intake with pipercross panel filter
NGK PFR7B plugs
3 port boost solenoid
Standard maf
Apexi power fc

Any advice would be appreciated Thanks, Nathan

Darc174

iTrader: (13)

not good news mate

i have heard a few of the VF23 going on 1.3bar, i have heard these shouldnt be pushed to 1,3bar of boost as they cant handle it.

i wouldnt rebult it i would go for a bigger VF or a TD05

darc

Jolly Green Monster

iTrader: (4)

Sorry to read that Nathan.

1.3bar is never normally an issue on this turbo.. not sure where you have heard that Darc.. numerous are running more without issue.

Yes the blades are never wonderful and going beyond 1.45bar would be silly but 1.3bar is well within safe margin imho.

Simon

Darc174

iTrader: (13)

yeah like i said simon its just what i have heard and seen a couple in the past few weeks go @ 1.3.

its not facts though as i dont know nothing about limits and mapping

darc

James Neill

iTrader: (1)

Sounds like the same thing as happened to my car. Had API rebuild the whole engine as there were bits of turbine blade throughout the engine. Spec is at the bottom here

https://www.scoobynet.com/scooby.php?profileid=211

- Wiseco pistons
- Race tri-metal crank bearings
- API steel rods and crank
- Ported headers
- TD05-20g Turbo
- ARC top mount intercooler
- Nismo 550cc injectors
- Rebuilt gearbox
- 3" Revolution full system exhaust
- Remap

driveeminpushemout

iTrader: (4)

Yeah just one of those things I suppose, I was all for running more boost but simon suggested that was enough!

I'm just wondering, If I change to a vf35, or a td05 whether the exhaust will be too restricive, or the injectors will need changing or whatever... i.e is it just a matter of changing the intercooler and turbo and expecting 330-350 bhp or do I need to swap the exhaust, headers, up pipe, injectors, in which case I'd consider putting another vf23 on and hoping for the best!

James Neill

iTrader: (1)

My understanding is that a 2.5" exhaust is good for up to 350-360bhp. After that a 3" is better.

scooby1doo1

iTrader: (7)

your 440s will be ok on 3.5 bar and a vf34-35 not 100% sure but i think they map vfs to 1.35 but keeps boost to redline( sure sombody with the vf34-35 will fillin the safe boost maped, the vf will also be ok to 350, you should see 330-350 max, after 350 you will need supporting mods and dif turbo. If you intend changing the topmount, fit a front mount as these can be had for around £350ish harvey i think.

driveeminpushemout

iTrader: (4)

So basically I'll be limited by my injectors before anything else... Perhaps I'm best sticking with the 440s and get a vf34/5 and an intercooler so I'm not tempted to go for more power again and end up needing to spend more on a gearbox etc!

With the spec I'm suggesting, am I likely to see much of an improvement with ported headers and up pipe, or will standard be fine? Also would it be a good idea to get rid of the standard maf, I've heard horror stories!

Thanks, Nathan

53

iTrader: (41)

You can get your 440's flow matched and flow increased by Lateral for £165.

driveeminpushemout

iTrader: (4)

will i gain anything by this if I'm only going for a vf35? i.e will the standard 440s max out before the turbo?

53

iTrader: (41)

Possibly but the TMIC would be the next safety/restriction before that

scooby1doo1

iTrader: (7)

If you want to sick around the 330-350 mark just keep your 440s and change the turbo.
Porting headers and uppipe will lower spool on the 34-35 only by around 500revs,( but at 350 standard headers are fine) uppipe will still lower spool, as for the maf it's down to air filters used as the 99-00 mafs are weak, Not sure on you maf. Induction go for apexi, green if you want to replace oe.

Think i have coverd most, if any thing is not 100% somebody will be along to put you stright,(and me)

trevsjwood

iTrader: (2)

Turbo Technics, Northampton, do a VF23 replacement, which may be an option

driveeminpushemout

iTrader: (4)

I'm about to start building it back up. I've bought a sti7/8 topmount off here and am looking for a good vf35, so anyone who has one, sell it to me!

Just wondering which head gaskets to get, and where from. The ones that were on there are steel ones and measure 1.6mm now that they're off. Does that mean I need 1.6mm ones, or is that the compressed size??! I've found these off someone I've bought other stuff from on ebay, are these the right ones? They say they're a replacement for early fibre gaskets, am I right to think thet're the correct fitment?

Subaru Impreza 1.6mm Cometic Head Gaskets Fibre Upgrade on eBay, also, Subaru, Car Parts, Cars, Parts Vehicles (end time 02-Jul-09 11:03:42 BST)

Also, I presume I only need new head bolts, and not cam bolts too?

Thanks, Nathan

Stealth

iTrader: (4)

Mate, buy bigger injectors as well, you don't want to be running 350bhp on 440's, I should think that will practically max them out and there is no way you should be running them at 100% you will find yourself back in the garage before you know it....... Don't cut corners now and you will reap the rewards.... doing something badly means you only have to do it twice