Boost levels

Finally fitted my boost gauge and I'm wondering if the following boost levels are normal for a non-chipped/mapped Tdi with pp502's:
- spiking to 19psi max
- running between 13 to 14psi at 90mph (140kmh) on a level road.

Finally fitted my boost gauge and I'm wondering if the following boost levels are normal for a non-chipped/mapped Tdi with pp502's:
- spiking to 19psi max
- running between 13 to 14psi at 90mph (140kmh) on a level road.

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Yup thats correct. With PP520 and stock ECU, i was spiking around 19psi and level off at 1 bar.

Thanks for the info.

Now to fit my newly acquired Boost Valve and go for the remap.

Fitted the boost valve today - the one for the A4 Tdi which is supposed to limit boost spikes. Took the car a run and I am still getting spiking up to higher than what I thought previously i.e. 21psi. Anybody out there understand how you adjust it - it says turn it in one complete thread at a time and check the boost level on the dial. I have followed the instructions and I am still getting spikes. Anybody fitted one of these before?

Is there such a thing as PP "502's?"

Is there such a thing as PP "502's?"

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There most certainly is! Kerma sells them.

--Matt

OK, the Boostvalve is a ball with a spring on top of it.

Turning the knurled handle in the tightening direction compresses the spring, so more pressure is needed to unseat the ball (ie bigger spikes). Unseating the ball basically applies some of your boost to the vacuum actuator for the VNT, causing the VNT actuator to reduce boost.

So tightening the knurled handle increases allowed boost, and loosening it will reduce boost.

Keith

OK so if I unscrew the knurled nut this will decrease the pressure on the ball and allow more pressure to be bled into the line. This enables the pressure from the spikes to 'adjust' the VNT and reduce spiking?

Regards the pp502's - I have a set of pp520's in my wifes 2002 Tdi and the pp502's in my 2001 Tdi. I used to have the pp520's in my Golf and then they were changed out to the pp502's. The difference between the pp502 and pp520 nozzles in my opinion is considerable.

I have been driving with the boost valve on now for two days. The car seems to run better and hold the boost better especially between gears - am I imagining this? Anybody any experience of the boost valve when fitted on a 2001 Golf Tdi?

Anybody out there willing to comment or have I lost the plot?

Cant comment on a 2001 car but with my 96 seat it made a big difference, i set the dawes to 17 psi peak, i have since got rid of my "td" tuning box for a superchip and WOW what a difference, far smoother and flat spot gone. Just waiting to fit my newly aquired kerma .216 nozzles.

I have been driving with the boost valve on now for two days. The car seems to run better and hold the boost better especially between gears - am I imagining this? Anybody any experience of the boost valve when fitted on a 2001 Golf Tdi?

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I believe you are fine.

I think these cars should all have boostvalves!

They make a huge difference in being able to park your boost levels where they can do the most for you, especially when modded...which makes power delivery so much more predictable and smooth.

Keith