37 replies to this topic

[nickknack]

I have a rev D and did the line 1 mod. Didn't notice any difference but I left it like that. Hasn't broken yet

[duncanm]

line 1 is ECV IACV mod.

[natho]

i would say it's not worth doing the mod to the IACV line if you're doing a tune. you can adjust the timing for the IACV opening anyway, and i found that i actually needed it to open quicker with the ported ECV than without.

[duncanm]

back to the original question..

 

school of thought says the line 10 BPV bleed is there to smooth out the transition from off to on-boost.. which is a particular 'feature' of the TT when cruising around 3000rpm or more - since its so quick to build boost at those revs. I know mine is so sensitive with the hose-10 mod in place that cruise control gets a bit silly at times throttling up and down trying to maintain speed.

 

It doesn't (shouldn't) affect BPV operation when at full throttle.

 

So when tuning -- it won't affect your open-throttle power runs -- but may change the behaviour around low throttle openings - where the tuner may be playing with closed loop operation and throttle response, etc. (I'm just guessing here)

 

Best (I think) would be to talk to the tuner, and make sure you've got the setting (hose 10 mod yah or nay) that you plan to keep after the tune.

[LukeFranky]

i would say it's not worth doing the mod to the IACV line if you're doing a tune. you can adjust the timing for the IACV opening anyway, and i found that i actually needed it to open quicker with the ported ECV than without.

- Good to know. I can't find a 0.8mm pill so I won't bother to keep looking. Thanks.

 

 

It doesn't (shouldn't) affect BPV operation when at full throttle.

- Hmm, I believe you but I also read the following in the TT guide...

I removed the tee piece today and new vac lines. I was running around 16 pound on secondary. Now it's boosting at 18. Great little mod. 

- I assume that was because he had an after market BOV?

 

Given your description of how it may effect low throttle positions I will leave it stock for now as that's where I get the trouble with surging/pulsing boost.

[LukeFranky]

On side note:

Out of interest I was looking around at top mount intercoolers. Turns out the B4 IC works about as well as an STi one. The only way to improve it is to go aftermarket, of which I could only find one and it wasn't cheap. 

[LukeFranky]

Well the tune is in!

He found a couple of boost leaks I didn't even realise I had. Had a major battle navigating around the piggyback ecu that we discovered. He almost gave up but had sudden brainwave when he realised the second set of green plugs that he was looking for were part of another 4 pin plug (usually 2 pin). We also had to apply 12v closer to the ECU to get the flash voltage right.

Once we got around those dramas he tweaked his tune once more and apparently everything is now spot on. Don't have a piece of paper to prove it but he said we cracked 200kw.

It was only a road tune this time around but that was much cheaper than taking it to the dyno. Pretty happy with the result. Car accelerates very linear now. Fast and smooth!

If I want he will tweak it on a dyno later.

[duncanm]

Good to hear you finally got this all sorted.

[motoboy76]

Top stuff Luke, enjoy.....

[Mmmbye]

Would an aftermarket exhaust manifold be worth it in terms of power, sound and efficiency gains?

[LukeFranky]

Short answer: yes.

I paid $250 for my mild steel system secondhand. Nice deep rumble but doesn't drone. Performance definitely was improved, even before getting it tuned.

[Mmmbye]

Awesome, I might give that a go if I can find a cheap one. Is it difficult to install?

[LukeFranky]

No. Exhaust installs are pretty simple. Just a few bolts and an O2 sensor to remove.

[Mmmbye]

Do you reckon a jdm set would fit a vf33 and vf32 I think I have?

[LukeFranky]

Do you mean a JDM set of turbos to swap with your current turbos? Or do you mean a JDM exhaust?

[Mmmbye]

Nah I meant would a jdm Set of headers bolt up to an audm b4?

[LukeFranky]

If they're twin turbo headers, then they should fit. I'm unaware of any changes to exhaust side of the turbos, so headers and dump pipes should be identical.

My exhaust is a turbo back system. My headers are stock as a rock.

[Mmmbye]

Oh sweet. Thanks for that