The mk3 1.9L TD power-quest

**Greg Roles** · 29-12-2009, 09:51 AM

I am SO jealous of your ability to just bung on a turbo, fiddle with the fuel screw etc, and away you go. If i was to try that, it's be at least $1-$2k for a custom chip tune each time. Might have to get myself an old school oiler for a project car! Keep up the awesome work dude!

**Preen59** · 29-12-2009, 03:37 PM

Excellent.

**schoona** · 29-12-2009, 04:32 PM

Just got a whiff of.....sweet project Aydan

**gldgti** · 31-12-2009, 09:56 AM

couldnt wait - new turbo in bolted up (worked on nights after work). just a few little things to finish off before test dive tomorrow - WOOT for public holidays!

**gldgti** · 31-12-2009, 09:53 PM

couldnt wait.... test drive complete

**gldgti** · 01-01-2010, 04:18 PM

ooooooooooooooooooook.

so, ive done a little tinkering today and i'm very happy. wastegate working well, i now have boost control.... which means i've been ale to see just how this baby goes. turbo performs well so far, i havnt really gone easy on it, i figure journal bearing turbo should be fine from the get-go.

max boost in each gear:

1 - 10psi
2 - 16psi
3 - 18psi
4 - 21psi
5 - 23psi.

lag is there,but less than with the merc t3, i think. not reeealy sure, since without a wastegate i couldnt floor it with the other turbo. off boost performance still good. very very rough 0-100km/h on wet road about 8.5-9 seconds (by myself, no helper for timing

)

no bad noises, turbo makes a nice whine up to about 5psi then its all whoosh. i'm sure i've lost a fair bit below 2500rpm with this setup, but now i can rev right out to 5000 with ease. just pulls and pulls. 100km/h in 3rd was not an option with the t2, now its easy. very predictable power, lag means the torque builds smoothly but if you get on hte throttle early you can make up for it a bit. just need to learn my way around it

above 3000rpm, the car is a beast. really storms ahead. definately an open road car now too, much nicer at speed with some load to bring the boost up quickly. at freeway speeds its great. my new favorite gears are 2nd, 3rd and 4th. 5th now feels long (used to feel short) but still great for cruising, its just that to really get the benefit from all the power in 5th, you would need to be doinga LOOOOONG way over the speed limit.

EGT's peak at 620*C, so i'm still below the red zone. considering i've turned the fuelling down so much, i really think this setup is oing to return much better economy. time will tell

pics to come

**Jarred** · 01-01-2010, 04:34 PM

Wikid! I'd love to have a mk 3 oiler!

**Preen59** · 01-01-2010, 05:16 PM

Fantastic dude. Nice work!

**gldgti** · 21-01-2010, 05:59 PM

well, its been a couple of weeks on the VW spec T3 now.

its funny - i've effectively neutralised the wastegate actuator on this turbo now by closing off boost pressure to it, but i'm still only seeing 21-22 psi max. I'm pretty sure this is because the spring in the actuator is soft, and exhaust pressure is pushing the valve open at high exhaust manifold pressure.

without pulling the turbo, my only option to combat this will be to run some vaccuum to the boost can on the actuator to try and hold it closed - this is a project for the coming weekend.

i am planning on using the existing, leftover solenoid valves from the electronic boost control for the T2, to switch vacuum off from the actuator at high rpm so i dont overboost.

i have to admit however, i'm as yet not sold on this turbo. i'm sure the exhaust side flows well enough for my needs, but the compressor side just seems a little small. i'm considering pulling the turbo and swapping the merc spec compressor wheel in, along with the compressor housing. this means having a kind of hybrid VW exhaust side with merc intake side. my only reservations about this are that the assembly could be off balance when i do this.... so i havnt convinced myself yet that this is a good idea.... however, i reckon the plusses could be huge - i'm fairly sure i was getting much better low rpm boost with the merc turbo, purely because the compressor side was so much larger, it would pump a good amount of air at lower shaft speeds.

performance? well itsp pretty darned good. i cant really get a good launch without smoke, there's just not the boost in 1st that there used to be. trick seems to be to rev first way out, change fast into second and maintain about 8spi between the shift to ket a good kick into 2nd. second is similar, rev it right out to 5000, fast change to 3rd, maintain about 14psi into next gear. that 2nd-3rd change feels HUGE off the clutch, lots of pull, then rev 3rd out to about 4700 and change into 4th. 0-100 is somewhere between 8-9 seconds, i still havnt tested it properly, haha.