Diverter Valves - Dealer says....

[svvg]

Hi All,

A slightly different question to "what's the best DV for my car...." - there's lots of info on this site and others to suggest the revision G DV holds better boost, although may eventually fail (as the diaphragm can tear), vs the revised version D - which won't fail in the same way, but which can leak boost and make the car feel less responsive and affect idle. It also looks like the Go Faster Bits DV (GFB DV+) seems to be a great solution for remapped cars (not sure if any point on a standard car though??).

I've just bought an 05 plate mkV and am giving it some tlc, and the local VW dealer parts guy (who seemed very knowledgeable and wasn't pushy or anything to his credit) told me that the mkVs had different K03 turbos fitted from the factory. Some K03 turbos were supposed to have revision G DVs from factory and some K03 turbos were supposed to have revision C DVs from factory, depending on which K03 turbo was fitted (I know the ED30 has the K04 turbo - but otherwise, this was news to me?). He then told me that the Revision C DVs have been replaced by revision D. So if you originally had a revision C DV, you now need revision D - and not revision G. If you originally had a revision G, then you still need a revision G and not a revision D...

Anyone able to shed any light on this?? I have some experience of turbo cars and a reasonably sound understanding of how they operate (I've got a big horsepower Impreza track car.... although, come to think of it - I've removed the DV on that now and have a large external waste gate and a roller bearing turbo... but I digress....) - and it didn't really sound right to me. Either the DV holds boost or it doesn't because the spring, diaphragm or seal can't cope with the pressure/is rubbish (the standard recirculating DV on an Impreza can be pushed in with your finger, whereas a forge recirculating DV absolutely can't...) - and it's unlikely that the diaphragm vs piston set-up on the revision G vs the revision D will affect the map or driveability of the car, unless the DV is weak and leaks boost...??

Grateful for some thoughts. The other option is to just replace it with the GFB+ option - as they are not massively expensive - and I "might" go for a stage 1 remap as some point - but for the moment it's completely standard and am wrestling with "stock", as our US friends like to say, vs making it work the way I want it to!

Thanks for your (constructive!) thoughts...

SVVG

[f00glee]

Hi There,

All DV's (rev C/D/G) are interchangeable. I went from C to G before being mapped to stage 1. Have since done ~15k miles at raised boost levels and the same rev G DV is still fine. It may fail eventually but is fairly trivial to replace. Id also heard the same about rev Ds leaking.

The story goes that D was an attempt at a different design to get round the diaphragm failing all together, which in turn had its own issues. VW went back to the diaphragm design and just made it a good as this design would allow for G. It still may fail but will last a lot longer than a C and not potentially leak like a D.

[muff1991]

I too heard the same jargon from the dealer, countless times I argued to say yes but the G this and that etc. There system recommends D for these turbos yes, but as mentioned, they leak etc. Bottom line, unless you wana spend the extra and put in a solid fix for near enough forever the go for the GFB, otherwise just get the G despite the dealers recommendation. I have had both G and D fitted in the last year and just prefer the G. If you want to stay OEM then get the G mate :-)


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[svvg]

Thanks both. Very clear and helpful advice. Grateful to benefit from others experience! G it is...

[colesey]

I’ve had the C, G and GFB on a stage 1 k03 car. The rubber of the C burst and the G became leaky. Replacing it with a GFB @3 years ago made the car quite a bit more responsive and I haven’t had any issues since.

[Bigmun123]

I have the GFB on my Stage 1 GTI, holds boost well and has never had any issues at all and it’s been on my car for a couple of years now! Recommend that


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