120 replies to this topic

[duncanm]

There's a whole lot of single conversion info here - if you haven't yet come across it  https://www.dirtyolb...sion-thread-30/

 

As you say - mostly 20R, though there are notes on 20H.

 

I have also come across (somewhere) a conversion where they just used the TT ECU, left all the solenoids connected to keep it happy, and an external boost control (MBC or EBC).

[Ordex]

 

go back - read first post - keep mouth shut next time...

all good, because you're right - BG5A should have a wastegate on the secondary usually, and this was something that was confusing me when I first got the car.

 

 

There's a whole lot of single conversion info here - if you haven't yet come across it  https://www.dirtyolb...sion-thread-30/

 

As you say - mostly 20R, though there are notes on 20H.

 

I have also come across (somewhere) a conversion where they just used the TT ECU, left all the solenoids connected to keep it happy, and an external boost control (MBC or EBC).

 

Thanks for the link, I'll have a look through the notes.

Basically your last point is what I was wondering was possible, but it almost seemed a bit crazy to think it could work. Maybe not after all. It would save a heap of hassle not having to repin the loom or find a new ECU! I'll see what I can dig up.

[duncanm]

ping robbks .. http://sl-i.net/FORU...1502#post161502

 

I think he hangs around here..

[LukeFranky]

I have a VF21 and VF32 secondaries and a VF33 primary. I am unaware of any issues with the secondaries.

As I said, the VF33 was a bit noisy before being removed. I did rebuild it 25,000km ago and it was still boosting strong though.

[Miguel]

The 4 plug setup in prefacelift gen2s is very similar to the 4 plug setup in gen1s and v1/2 wrx. I don't know the specifics bit I believe you'd be able to change a couple of pinouts to run a single setup no dramas. 4 plug single turbo ECUs are also plentiful and come in a bunch of different variants. The 20H in your car is pretty much the same engine as a v1/2 wrx 20G

[Ordex]

Ok it's good to know that's the way forward. For now I'm going to whack everything back together so I can at least drive and start collecting parts for a possible conversion.

I'm still interested to know if a total engine swap would be less work?

[Ordex]

Does anybody know where I can buy a new gasket to go between the ECV and secondary turbo? I've looked on PartSouq and done lots of googling but it doesn't seem to exist! It's a D-shaped gasket. I can probably reuse the existing one with some exhaust gasket goo, however I'd prefer to go new and not have to use the goo.

[Miguel]

Unfortunately you can't buy it. I had a mate of mine translate the writing on the FAST-II diagram(Which is the same for all TT's)

 

 

What it says where the arrow is pointing to the gasket is...

 

 

 

Unfortunately, it says that gasket is "not separate-able" and thus is "not available for individual sale."

 

Looks like they want you to buy the secondary and the ECV as an assembly

 

Secondary assemblies are a cool 3.3k online :S

[duncanm]

sheet of exhaust gasket material and a knife.

[Ordex]

Thanks guys, guess I'll stop wasting time searching online for it!

[duncanm]

hey I had another thought about that gasket...

 

why would it be any different to the primary up-pipe/turbo gasket: 44165AC010  is the BE/BH #, but Gen2 probably the same.

 

Are the turbo inlets any different between primary and secondary ?

[Ordex]

44165AC010 is a T-shaped gasket also used on the BG primary up-pipe.

 

This picture shows the difference between the primary and secondary inlets:

[duncanm]

ooh yeh -- somewhat different, eh!

[Miguel]

Completely different because ECV. Annoyingly every single other gasket is the same though.

[Ordex]

I ended up getting the gasket on the secondary exhaust inlet, as well as a couple to go between the down pipes and mid pipe of the exhaust made up by a speciality industrial supplies shop. They were able to do it for less than I would have been able to buy the material myself and definitely did a much better fabrication job than I would have been able to!

 

I've got both turbos and exhausts bolted all back together. It's pretty well almost ready to fire up except I'm waiting on a few more ancillary cooling hoses I want to replace. I've just about replaced all the cooling hoses now, including both upper and lower radiator hoses, and put in a new radiator as the plastic on the old one had rotted.

 

I'm interested to know what anyone thinks about priming the turbos before starting the car?

I've read about people pouring oil into the turbos before attaching the oil feed banjo bolt, or cutting the fuel so the engine just kicks over a few times to and gives the oil pump a chance to get some oil through the system before firing it up properly. Others just seem to start it up and not worry about it! Neither turbo is brand new, but I'm not sure how much oil would be left in them as I saw a fair bit come out during removal.

[Robert]

I just pull a fuse so it won't start
Crank it over until it gets oil pressure

Not a bad idea to prime the turbo with water too (through the coolant lines obviously)

[Ordex]

we've had some nice weather down this way recently so update time!

 

I didn't have any issues firing the car up for the first time. As suggested I pulled out the IGN fuse (I used this thread to work out which fuse it was because my fuse box is in Japanese). For good measure I also unplugged my fuel pump just in case the translation wasn't spot on.

 

First thing I have noticed is the primary turbo (VF18) has a definite low drone or hum while the car is idling. I'm not entirely sure this is a good thing. It makes boost, although not as quickly or as much as I was anticipating. I'll report back on numbers when I've done some more road testing.

 

On the plus side, after replacing all bar 2 of my coolant hoses and the radiator I have not heard any coolant gurgling noises from the turbo return lines after switching off the engine, and the waterfall noise in the heater seems to be diminishing each time I take the car for a drive.

 

As I now have a VF32 secondary off a B4 are there any issues having mis-matched combos? For example if I decide to ditch the VF18 could I stick on a VF26 and run a 26/32 combo? The reason I'm not keen on the idea of using a VF33 is I don't want to have to deal with the larger intake and outlets.

[Ordex]

Just went for a test drive with NO boost control (ie. nothing hooked up to the wastegate). Couldn't get it to make more than 0.6 bar (8psi) on the primary.

[Jimbo]

Sounds like the ECV is open when it shouldn't be. Did you get it past 4000rpm to see if it runs on both turbos?

[Ordex]

Jimbo that's completely possible as I had to dismantle the ECV to remove the secondary turbo. To be honest I didn't want to push into secondary range while I didn't have any boost control.

 

I did however follow your instructions on the Your Guide To Twin Turbo page to readjust it when putting everything back together. I set the ECV to rattle mode and then wound up the rod about 3 times.