293 replies to this topic

[TSG]

I remember you trying to convince me to buy your wagon Robbks, pretty sure it was you anyway.

 

Those that have tried to modify the TT all have their sob stories. It's best to just enjoy it for what it is (if its working). If you want the car to go like the WRX you should have bought, single turbo conversion. That's the only point we make when we defend the TT. Some people (like myself) only drive theirs to work, and give it a squirt on the weekends. Granted this guy probably is a candidate for a single conversion. But some people just want their once working TT, to work again.

 

I guess it depends on your mindset. I have no intentions of converting mine until it becomes unrepairable or beyond the cost of keeping it that way, provided the motor itself is even viable for the transplant, it might be too tired by that point - its already done 174k and still makes boost no worries. I doubt it would cost a grand to single turbo convert.. I'd be impressed to see it anyway! About 3k you're probably getting closer.

[WillC]

. I'd be impressed to see it anyway! About 3k you're probably getting closer.

 

Do it properly this is what you will need.

 

Rebuilt bottom end / factory or upgraded up to your budget. $2k - 20k

New headers wrx bug eye. $200 - 700

Service your heads $ ~600 - 700

New dump wrx - $200

New clutch - $600

New ECU Bugeye JDM 01 - 02 - $200 - 600 <-- JDM ones don't have immobilisers so your immobiliser wont work anymore.

New ECU Bugeye ADM 01 - 02  $150 - 200 <-- You will need to get your standard key put back in the wrx ecu. This is 100% doable and a cheaper option and better as you will still have your immobiliser.

Turbo - $ 200 - 800 or $1300 for a new VF34P20.

other bits hoses oil filters/ clips / oil and just shit you break and screw up along the way - $1000 - 2000.

Tactrix ECU cable $ 130

AFR Gauge with data logger because you are paranoid like me and want your car to run right. $210

Intercooler Y Pipe $100

 

 

Tow your car to MSR - no idea

Michael South or another good tuner to tune your car. (depending on what needs to be done ~$800 )

 

So doing it yourself, you can probably get away with 6500 with a decent build.

Feel free to correct my figures on parts guys. But lets try keep the costs accurate.

[WillC]

You will need these documents to do your pin outs on the ECU. Once you have moved the pins successfully you will have a Plug in WRX ECU.

 

 Subaru B4 to WRX ECU MAP.zip   118.27KB   9 downloads

 

Front o2 sensor B137 Pin 18 B4 ECU move to

Front o2 sensor B136 Pin 7 WRX ECU. 

 

Also you will need to extend the harness wire for the o2 Sensor as it is on the left hand side of the B4. WRX's have front o2 sensor on the right hand side of the car.

 

Wastegate control solenoid valve, this depends on your turbo. The stock restrictor pill is too small and needs to be upgraded. For a VF34P20 you need a 1.1mm restrictor pill. This valve is can be found on the left hand side of your B4. To get to it. Remove your headlight and remove your battery. Undo the bolts on the left hand side panel where the battery was. This is what you are looking for inside your guard and it is perfectly OK for you to use the factory one on the B4. It holds boost perfectly.

 

 20140301_181455.jpg   114.38KB   5 downloads

 

 

 

 

[Mbooma]

Yep defintly to much effort ill just fix mineget the turbos hiflowed new exhaust an front mount an gofrom there lol

[TSG]

So doing it yourself, you can probably get away with 6500 with a decent build.

Feel free to correct my figures on parts guys. But lets try keep the costs accurate.

 

That sounds more like it, double it for an STi conversion. I've discussed it with Russell at SubiEvolution a couple of times while it was in for various things. He isn't too phased by the system, its just a pain in the arse. Shit got real when it started pinging late last year. But crisis averted

 

Yep defintly to much effort ill just fix mineget the turbos hiflowed new exhaust an front mount an gofrom there lol

 

Just find out what's wrong with it.. If you do any mods, open the exhaust up with a catback. (edit: found build thread). The stock IC is more than enough from everything I've read. Front mount might be too much for the twins... there are larger top mounts you can get.  If you mod it too much, it'll need a dyno tune again and if you start going down that path with it - you may as well single turbo convert it. Just pissing money up the wall otherwise.

[Jimbo]

BOV vacuum hose had snapped off, all boost pissing out BOV. First problem fixed. Says it still has boost "spiking", likely to be BCS.

[Tim.]

Just confirms that converting to single wouldn't have fixed his problem

[Robbks]

BOV or Secondary BPV.?

AS the BOV should still hold 10PSI under spring tension without assistance

[WillC]

this car is a pretty big project. I can't wait to see the improvements in the months to come. There's quite a bit to fix

[Jimbo]

Aftermarket intercooler BOV, big Turbosmart dual port jobby, vented to atmo. OP said the "whooshing" noise under boost stopped when i fixed it.

[Robbks]

vent to atmo is a terrible idea anyway
plumb it back in how it was from the factory

[Dav_fre]

vent to atmo is a terrible idea anyway
plumb it back in how it was from the factory

Doesn't that depend on wether your tuned for vent to atmo or not ?

[Robbks]

Apart from being illegal to vent to atmosphere,
The problem is, if there's an issue with the BOV not closing properly it can cause the car to suck in un-metered air, then run lean
And on a B4 that pings it's head off at the best of times, say good-bye to the big ends.

My TT had a plumbed back GFB Mach1 on it, through a Unifilter Ram Pod is was still very loud.
It was pretty tight so anything under 10psi would flutter and over that would vent.
https://fbcdn-sphoto...4_3544171_o.jpg



 

[WillC]

I hate the fluttering. I am looking for a good recirculation valve that will cleanly dump any air back into the system properly after throttle off. There are so many technical arguements for problems with the B4 TT. I'd say if you really love it, then be willing to invest good money on dyno time and be really ready to mod your B4. if you want a car to run properly at stock standard the B4 is not the beast for you.

[Dav_fre]

I have GFB 50:50 BOV, but have it set to plumb back 100%, just because of the legality, but it's good to onow



*know

[Tim.]

Not to mention, the air you vent to atmosphere is metered air. That's gonna mess with your mixtures and is something the B4 does not like.

[Robbks]

the Mach1 has adjustable tension (shims) so you can set it harder or softer to remove/ add the flutter.

Fact is, no matter how much money you dump into the sequential turbo system you can;t get around the inherent exhaust flaw at changeover,

You are taking all the exhaust gas under 4000rpm and directing it to the passenger side of the car,
then you open the ECV and have to reverse half the gas flow to direct it into the secondary.
That's on top of the hopeless restrictive intake.

you "could" re-manufacture the headers to run behind the engine to flow past the secondary up-pipe entry and into the primary
Then, when the ECV opens, the gas is already flowing in the same direction.

As for the intake, you could use something like this (fitted to my Leggy when the previous owner had it)
to help get more air into the primary via the standard intake pipe when the secondary is in operation

 

 BASH08 (21).jpg   190.29KB   1 downloads

 

[Dav_fre]

There are silicone intakes available for the B4 to solve that restriction issue.

But your right on the money with reversing and reversing exhaust flow during changeover.

The GFB 50:50 (9001 I think) also has spring rate adjustment

[Tim.]

Yeah, i've got the GFB and winding the pre-load up on the spring was the first thing I did. Makes for some flutter at low boost.

Fact is, no matter how much money you dump into the sequential turbo system you can;t get around the inherent exhaust flaw at changeover.

It's seamless if it's been tuned properly. I actually love the brief plateau and i have never thought "shesus I hate this car, there's something wrong with it, imma sell it FML". Never fails to put a smile on my face during changeover. That being said, i've never been for a ride in a BD5/BG5 TT.

95% of the time you shift before 4k which makes it perfect as a daily. Not talking dyno queen - as one it will never be.

[Mbooma]

Yea well after every ones info ill be working on the car today plumbin the bov back in an im gonna do an ecv bypass
But i still cant work out wat vacum line im missing on the bbod.... haha