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Discussion Starter · #1 ·
Hi guys just fitted a boost gauge today:) Psi

what are all you guys/gals running your boost at Eg: whats it max out at,,at present our is 10 Psi just scratching 11

mods ive done are as followed

Egr
Fuel turned Up
totally Modded Vw Exhaust flange "burred Out" to fit 2 an half inch bore New Generation Impreza pipe work "Zorstec can/silencer" side exit style..

any advice T:T:T:

T4 1.9Td 2001 ABL
 

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15 is what I also run - but for those that are just getting into this, let me just go over a few points.

The fuelling and boost need to be tweaked TOGETHER and then adjusted in harmony to produce the best results.

There's no 'right' answer for this - ie '1 1/2 turns of the fuel screw + 5 turns of the actuator arm = perfect.....

To do this mod properly, you need a base value - ie a PSI rating 'as standard' for your engine (they ALL differ a little) - anywhere from 7-10psi.

After that, you need to be able to compare both the boost reading and the 'feel' of the van as you make changes - noting any change in idle, smoke, mpg, etc.

Where you end up will depend on what compromises you're willing to make.....

For me, I was running about 13.5psi (max) prior to my bottom pulley bolt shearing (requiring a new head - nothing to do with this mod!!) and the van flew along. I was getting about 32mpg around town and the idle was OK, if a touch high.....(no tacho, so not sure of the revs)

On the new head, the boost was about 1psi down (no idea why, as nothing else got changed) and I was already at full adjustment with the actuator, so I fitted a MBC. It didn't feel as quick initially, so I made changes....

I'm now at 15psi (max) but the fuelling has been decreased ever so slightly, as there really was no gain in either boost or power at the higher fuel level, so I just droopped it until I could feel a change - the result is the revs are down at idle and the fuel consumption has improved to about 34mpg (around town).

The recent addition of 2 stroke oil has seen the MPG get WAY better, but it's early days yet, so I'm still waiting to pass judgement on it.

And if diesel carries on the way it's going, veggie oil is going back in too - as it's already about 10p a litre cheaper!!!

So - lots to think about above and beyond 'What boost should I run'.....

:)

It's now just about back to where it was, but the two comparable settings have changed
 

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Discussion Starter · #5 ·
15 is what I also run - but for those that are just getting into this, let me just go over a few points.

The fuelling and boost need to be tweaked TOGETHER and then adjusted in harmony to produce the best results.

There's no 'right' answer for this - ie '1 1/2 turns of the fuel screw + 5 turns of the actuator arm = perfect.....

To do this mod properly, you need a base value - ie a PSI rating 'as standard' for your engine (they ALL differ a little) - anywhere from 7-10psi.

After that, you need to be able to compare both the boost reading and the 'feel' of the van as you make changes - noting any change in idle, smoke, mpg, etc.

Where you end up will depend on what compromises you're willing to make.....

For me, I was running about 13.5psi (max) prior to my bottom pulley bolt shearing (requiring a new head - nothing to do with this mod!!) and the van flew along. I was getting about 32mpg around town and the idle was OK, if a touch high.....(no tacho, so not sure of the revs)

On the new head, the boost was about 1psi down (no idea why, as nothing else got changed) and I was already at full adjustment with the actuator, so I fitted a MBC. It didn't feel as quick initially, so I made changes....

I'm now at 15psi (max) but the fuelling has been decreased ever so slightly, as there really was no gain in either boost or power at the higher fuel level, so I just droopped it until I could feel a change - the result is the revs are down at idle and the fuel consumption has improved to about 34mpg (around town).

The recent addition of 2 stroke oil has seen the MPG get WAY better, but it's early days yet, so I'm still waiting to pass judgement on it.

And if diesel carries on the way it's going, veggie oil is going back in too - as it's already about 10p a litre cheaper!!!

So - lots to think about above and beyond 'What boost should I run'.....

:)

It's now just about back to where it was, but the two comparable settings have changed
,,yeah thanks for that info i do think the fuel could with been turned down a tad as she does chuck abit of black smoke out if ya just put ya foot donw as sat still drivers door open and give the pedal a good old floor,,its a case of having a mess till its good all round,,,,thanks for the advice & happy T4"ingT:T:
 

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No probs - it's a bit of a black art and I don't profess to have all the answers, but I guess having run it for so long, I have a bit of an idea of what works....... :)
 

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im gonna be fittin my mbc tonight - will see what hapens, as currently the actuator arm is as short as poss, and fuelling turned up to the point where revs start hanging on their own - yet i can only make 10.5ish psi boost, and dont get any black smoke at all????

so mbc is going in, get boost up to 14 - 15ish, then adjust fuelling till it goes better - im guessing it might need backing off :)

I am already getting roughly 35mpg though :)
 

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Using a RR would give you the peak torque and power settings so would definitely help seeing what worked and what didn't - but I reckon it'd take a fair few runs to dial it in.

Doing it on the normal road took a dozen or so test drives, and even then, you need to live with it for a few days or weeks to see if you can stand the extra cost of fuel and rev increase.

I'd say do it without the RR until you've found a compromise that you're prettyhappy with, then get it on the rollers to fine tune the settings and make sure you're getting the best power curve for the minimum fuel wastage and rev increase.......
 
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