The mk3 1.9L TD power-quest

**Goon** · 09-12-2009, 11:11 AM

Just read this entire thread! Wow just wow..

I wish there were more older VW Turbo Diesels around! I want one!!

Excellent work mate, I'm extremely envious of your skills.

**DVR68U** · 10-12-2009, 12:30 PM

looking good as always ,
cheers brenton

**gldgti** · 10-12-2009, 08:41 PM

i've been working on my new intake manifold after work this week and have something... but i'm not entirely happy with it - i have doubts about its functionality. aesthetically is pretty rough for sure (still unifinished, but still rough anyway) but its sound.

my deeper concern is that it will work not better than the stock manifold insofar as i want to balance the airflow across the cylinders. i fear i may be cutting it up tomorrow. but i figured pics are warranted so you can see what i mean:

**Preen59** · 10-12-2009, 08:56 PM

Some of those welds are pretty good for an amateur dude.. (To Aluminium.. Not TIG welding in general)

I think that should work ok. When you think about it, it looks restrictive but it isn't really. It's larger than having runners so i think it will be ok. I'm not 100% on how diesels react in terms of air speed etc but with FI it wouldn't matter as much, would it? It looks a little unorthodox, but i reckon it will be ok..

Why did you make that "runner" so long? clearance?

**Greg Roles** · 11-12-2009, 05:35 AM

I agree with the Preenster, given the fact diesels run a lot higher PSI, all you are basically doing is pressurising the chamber against the closed valves, and that pressure will run in when the valve opens. The only potential issue may be a little lag given the volume over stock?? But then you've now got a bigger turbo!! i reckon it's a goer.

Best bet is usually the bummometer!

**Preen59** · 11-12-2009, 07:20 PM

Yes a calibrated bummometer is highly accurate.

**gldgti** · 11-12-2009, 09:31 PM

ahh fellas im not worried about restriction (cross sectional area of that recangular section is same as a 4" pipe) i'm concerned about flow distribution.

firing compressed air into the inlet has air coming out faster at the back end port and least at the near inlet side port, so i am guessing that this is not what i want.

today i made a decreasing cross section plenum and welded it up to the side of the top plenum (duel plenum type design) but although it worked better, it wasnt perfect. so, for now its on hold. the old stock manifild will go on for now and i shall be working on the manifold later.

on the plus side i have my new oil lines and everything else i need to have this running once back together. WOOT. i have a big weekend ahead

**evorobin** · 12-12-2009, 07:42 AM

Master oil burner watch this turbo build with much anticipation we do

**Preen59** · 12-12-2009, 08:42 AM

Originally Posted by gldgti

ahh fellas im not worried about restriction (cross sectional area of that recangular section is same as a 4" pipe) i'm concerned about flow distribution.

firing compressed air into the inlet has air coming out faster at the back end port and least at the near inlet side port, so i am guessing that this is not what i want.

But.. That is with an open end. Wouldn't it be different once you block it off and put 4 valves across the bottom? I understand what you mean from a fluid mechanical point of view, but i would think it should pressurise that chamber evenly and should give a close to even charge distribution?

Good luck dude.. I'm off to Sydney for the weekend so i'll be keen to see what you came up with when i get back sunday.

**gldgti** · 13-12-2009, 09:52 PM

yeah, so big weekend. not everything went according to plan, but hey, does it ever?

only 1 little hitch really - i had to move the wastegate actuator with a little bracket slightly because of where i wanted to point the compressor outlet. this put the wastegate actuator in a position where it fouled the brake booster (just). unfortunately we found this out hte hard way (once engine was in and the actuator air hose tap had broken off.)

anyway, being the renegade dieseler i am, we removed the actuator completely and bolted the wastegate shut - so i have no boost control, for now

apart from the foot, and the fueling, anyway

only other hitch is i have changed out the main engine mount for a BFI stage 0.5 one (the other two are already changed). this has resulted in more vibration than i want, so it will be changing back to a stock one shortly....

oh - and i didnt get to finish my new intake manifold, but i couldnt have used it anyway because i didnt get one little fitting i needed for the oil supply line on hte turbo. this meant i had to use the old oil supply line, which in turn doesnt allow the use of big fat inlet manifolds (it isnt flexible)

pics...

how does it go? well early days yet, but its hit 23 psi in 1st gear easily. spools after 2000, fast after 2500. i have to turn the fuel down a fair bit i reckon, i can get mega smoke if i try. off boost performance is WAAAAY better - engine revs much more freely and with purpose. still has lots of torque, but doesnt seem to be trying at all.

on boost performance is also way better - but this is something i havnt really explored yet since the wastegate is shut and i have the fuel still turned up, the damned thing just wants to boost so much i chicken out with loud pedal very early.

how does it sound? good. very good

actually, surprisingly little turbo noise, just a little more exhaust note.