Single tubro project

[Guest]

Hi - just wondering if I could get some opinions from guys who have done this.

My 1999 BH5 GTB wagon blew up about three years ago - big end and associated swarf through the whole motor. As the motor had done 180,000km I decided that a rebuild was going to take too much time, money and energy. So I bought a 2001 WRX motor off trade me. We fit the motor in pretty easily, and then struck problems with the wiring.

Because there wasn't as much knowledge and info on the net at the time we managed to cobble things together to get the machine going. Basically it is now going - using the standard TT ECU, WRX engine, and Legacy wiring. The result is very little boost, and check engine codes as soon as you go up a steep hill and give it a bit of gas or high load situations. It is driveable but not that flash. You do get used to driving slowly and avoiding hills unless you have a bit of a run up.... ;D

I have been quite sick for the past 2 years, and haven't had the time and energy to sort things out. But now I am feeling a bit better and want my Legacy back 8)

(I am sick of driving the POS Ford Mondeo that I bought as a stopgap!!)

Having gone through these forums as much as I can, I have found the threads by RuebenH and others and gathered a lot of information that will help me sort out the vacuum hose octopus so that I can tidy that end of things up. Very helpful - thanks guys!

I bought what I thought was a 2000 WRX wiring loom and ECU off Trademe which seemed like it might do the trick. But it seems like it might be out of a standard imprezza instead and not much use, as it has the wrong plugs and a weird model number.

My question is which is the easiest path to follow - go for a G3 Link and wire that into the system, or buy a 3 -plug WRX ECU and wire that in? I have the original yellow top injectors, plus the standard TT AFM, however the turbo is only a TD04. I am not after the fastest Legacy, but want reasonable performance (with some boost!), and smoothness cos I am sick of using the car as it currently is.

Also I am not that familier with the V2/3 and V5/6 terminology you guys are now using. I am guessing that V1/2/3 relates to pre '96 WRXs, and v5/6 the facelift ones after '96??? Can anyone tell me which ECUs had 3-plugs?

Any thoughts or recommendations would be appreciated.......

[dubbedup]

go get a link G4 as this will solve all your problems in one hit... as even putting the 3plug ecu in can cause issues....(due to higher compression IIRC - Gazzy2000 has just gone thru this)

[gazzy2000]

wudnt a 2001 WRX engine have AVCS??

[Shale]

^ Yep.

Also... LEEEEEENK!! Expensive, but so full of win it hurts. It should kill a few electrical gremlins to say the least.

[Joker]

get same ecu for engine is it not obvious? (wait read post proper - hmm)

and yep I have heard of TT ecu's running singles/parallels

[gazzy2000]

well, if thats the case and you have an AVCS engine... Its going to have a be a Link ECU (or at least some sort of tunable ecu) there arent many other cost effective options, and there will be some wiring involved with that.

At a guess:

- S/H g3 ECU $1000

- tuno tune $700 +/-

- wiring mods ???

OR get the right factory ECU for the Engine and find someone to wire it up, cost = unknown

Failing that, sell the 2001 engine and buy a v5/6 engine and then you can properly do all the electrical mods required for a TT to ST on a BH, plus if its a proper v5/6 STI engine you can use a factory v5/6 STi ECU with it with no probs. (long as teh electrics are done, which is all documneted here on CS

[funkytown]

if its a AVCS model you have to get a G4, g3s im pretty sure dont run avcs..

[Koom]

 funkytown said:

if its a AVCS model you have to get a G4, g3s im pretty sure dont run avcs..

Firmware upgrade the G3 to G4......

But for a basic project (i.e. not going for huge power etc) I'd go with finding a factory ECU and wiring it up properly.

[NotAWhiteGTB]

 funkytown said:

if its a AVCS model you have to get a G4, g3s im pretty sure dont run avcs..

You need a g3 plus. But yes they do, my car is proof of that

[funkytown]

 NotAWhiteGTB']

[quote name='funkytown said:

if its a AVCS model you have to get a G4, g3s im pretty sure dont run avcs..

/quote]

You need a g3 plus. But yes they do, my car is proof of that

flashed to G4?

[gazzy2000]

options as i see it, layed out:

In order to save cash in your predicament youd fully have to do most the work yourself or you'll be in for a shock getting a garage to do it.

To use the AVCS engine you currently have, see option 3 and 4 or.... go stright to 6 if you cant be f&*ked ;D 8)

(1)

- get a new v7 shorty

- reuse the old BH TT heads (get them machined etc)

- then do the wire mods for the TT to ST BH model

- use a V5/6 STI ECU

- might have to buy a complete v5/6 inlet manifold in order to make sure you have the right Single Turb (ST) components.

- sell 2001 AVCS engine to recoup costs

or

(2)

- use the 2001 WRX shorty that you have

- remove the AVCS heads

- reuse the old BH TT heads (get them machined etc)

- use all the Single Turbo parts that he already has (exhasut mani, turbo n uppipe etc)

- shud be able to use his original TT manifold (if any ST bits are required/missing, they wud have to be sourced... by a whole v5/6 inlet manifold)

- Sell 2001 AVCS heads to recoup some $$

or

(3) - [edit] AFAIK never really been done.. using a factory v7 ECU on a BH

- find the right ECU for the 2001 Engine you have

- then see if the plugs are the same on a 2001 AVCS ECU compared to the BH, if not a full rewire may be in order (or maybe make up an adaptor i.e. going from your BH plugs to the AVCS ECU, the adaptor simply reroutes the wires into their correct pins on the ECU from your BH wiring.

- Extra wires would have to be run from the ECU for any AVCS sensors/components (your BH wont accommodate these wires)

- If the 2001 AVCS ECU is same or similar, i.e it plugs straight in, trace the wires and pin outs to make sure they are the same, change if nesscessary and/or run new wires for any components not there

or

(4)

- get a Link G3 or G4 that supports AVCS to get the 2001 WRX egine going (or what ever ECU the Clubsub chaps say to use)

- you cud use an insert Link ECU, not sure if AVCS v7 model come as an insert anyone... are v7 AVCS Link ECUs inserts?

- if not using a insert (inserts use the cars existing wiring) you wud have to get the link wired up.

- if you do manage to get an AVCS v7 insert ECU all the wires wud have to be checked that they go to the correct components, and if not modify or run new wires.

- get it dyno tuned

or

(5)

- buy a proper v5/6 STI engine

- get the v5/6 STI ECU that goes with it

- do the proper TT to ST wiring mods

- sell the 2001 WRX engine to recoup costs

or

(6)

- sell it to me ;D

[ReubenH]

Option 3 won't work in practice. A total reloom would be required, too much effort when you can just buy a link

I'd go with 4, or maybe 1.

[funkytown]

option 1 you talk of use the v7 shortie... and reuse BH heads

then sell the 2001 AVCS motor..

i think you mean sell the AVCS heads, as your using the ej207 on BH heads

*note, check both the BH and V7 use the EJ207.. i think they do.

[ReubenH]

Auto BH is EJ206, manual BH is EJ208. STi is EJ207. And AFAIK, WRX and Foz = EJ205.

Option 1 was pretty clear. sell the V7 rex engine buy a new V7 STi shortie and put the old BEBed BH heads on it, much like what chris did with his build.

[gazzy2000]

If it were me, i reckon id go with option 2 because:

(1) all the major bits are there, old BH heads, the v7 shorty

(2) no dyno tune or major wiring mods needed with factory v5/6 STI ECU, just the normal BH TT to ST wiring mods

(3) hopefully some of the v7 inlet manifold single Turbo compnents can be used, failing that get a v5/6 complete inlet manifold ($300-$400)

(4) Single Turbo exhausat manifold all there too

(5) can sell the AVCS heads

(6) do the work yourself with out relying to much on auto sparkys or tuners etc.

ofcourse the v7 shorty avoids issues with detonation as it will be the right compression ration

[ReubenH]

2 is a bad idea, it involves taking the heads off a perfectly good engine, to fix an issue with the ECU. Not good sense makes that does.

I vote 4, unleash the potential of what the guy has already!

[gazzy2000]

 ReubenH said:

2 is a bad idea, it involves taking the heads off a perfectly good engine, to fix an issue with the ECU. Not good sense makes that does.

I vote 4, unleash the potential of what the guy has already!

I hear ya, but thats just me, i was purely thinking cost wise that wud be cheapest.

Option 2 really is just the cost of a v5/6 manifold and a few other bits and bobs (maybe head gaskets) compared to a say a G4 wich wud be nearly $3000 for the ECU and a tune alone and any extra wiring mod or maybe a full rewire cud be $1000 to $1500, making say $4500 all up???

I reckon doing number 2 (if you did the work yourself) might cost around $1000, plus you cud recoup costs from the AVCS heads $300-400.

[edit] i guess if you got the BH heads machined and serviced the cost goes up, but is still cheaper that doing a G4. Plus i dont thik this guy really cares about a big wiz bang ECU and all the benefits that go with one, he just wants it to run, and goin from TT to ST on a GT-B wag no matter the technology combination, is better than the TT setup any day ;D, dont we know it ;D ;D

[NotAWhiteGTB]

 funkytown']

[quote name='funkytown said:

if its a AVCS model you have to get a G4, g3s im pretty sure dont run avcs..

/quote]

You need a g3 plus. But yes they do, my car is proof of that

flashed to G4?

Is now, but was a plain jane g3 plus until about 9 months ago

[gazzy2000]

heres a thought, sell your v7 engine and buy this

http://www.trademe.co.nz/Trade-Me-Motors/Car-parts-accessories/Subaru/Engines/auction-270938029.htm

[gazzy2000]

heres how much STI v7 heads sell for

http://www.trademe.co.nz/Trade-Me-Motors/Car-parts-accessories/Subaru/Engines/auction-271092718.htm

[ReubenH]

I'd rather a V6 sti engine over a V7 WRX one myself, without a moments hesitation.

[gazzy2000]

or some v6 STI heads

http://www.trademe.co.nz/Trade-Me-Motors/Car-parts-accessories/Subaru/Engines/auction-271328111.htm

[Guest]

Hi Guys

Thanks for the very useful information. I am now not 100% sure what to do as the options are a bit wider than I had thought. I am leaning towards trying to find a second hand Link, mainly because I did once train as an avionics technican (a long time ago!), and wires are what I am most familiar with. However I can see the merits in changing the motor which would make the car a more "standard" single turbo conversion (and more likely to work!), plus I can use some of the information from the various TT to single turbo conversions threads already here.

I will talk to my brother as he does know a couple of dyno tuners down this end of the country. (He races an old car and spends quite a bit on it which may help me)

Time to mull it over and make a bit of a decision.....

The thing is that I really like the car. I have had it now for 9 years, so have an attachment issue with just getting rid of it.

Thanks again for your help.

Cheers

Wayne