MK5 Golf GTI
All Things Mk5 => Mk5 General Area => Topic started by: Trav Turbo on March 26, 2018, 07:55:31 pm
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Hi all I've been running a Rev G DV on my car and has been great, I took it off today to check any splits and there wasn't any. Cause I've got a GFB+ DV as a spare I thought I'll try it cause heard loads of people say it's better and some say Rev G is better. Personally I think my car boosts horrible with the GFB and nowhere near as responsive with Rev G and I'm definitely switching back tomorrow.
I'm intrested in what's people's thoughts on GFB+ DV who runs them?
Cheers
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I do but have herd story’s of them lately,and considering buying a rev g
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I run a GFB DV+ and no complaints. I had a rev G in good working order before and noticed an improvement. I wonder why some people say they're worse than the OEM diverter valve. :confused:
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Pretty sure I've read on here about the pistons sticking on later versions?
It's put me off going for one anyway.
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I run a GFB DV+ and no complaints. I had a rev G in good working order before and noticed an improvement. I wonder why some people say they're worse than the OEM diverter valve. :confused:
That's interesting to hear. I was hearing GFB DV+ was great so I bought one. Then when I got it started hearing they ain't great and mixed views so didn't fit it for months then gave it a try yesterday. My car doesn't boost great with it and more of a build up boost and feels like I've got a slight boost leak. I've come into work early this morning to switch back to Rev G lol
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I run a GFB DV+ and no complaints. I had a rev G in good working order before and noticed an improvement. I wonder why some people say they're worse than the OEM diverter valve. :confused:
Same story here. Mine was fitted two years ago and the car runs both stronger and more responsively than the rev G previously fitted.
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Yeah there have been some issues with the newest revision since GFB 'revised the design to make the manufacturing process easier' or something along those lines. Mines been in over 2 years now and aside from me removing it a couple times to oil it (just for maintenance - had no issues) its been great and a great improvement over the Rev G... and its paid for itself since I was splitting Rev Gs every year
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I think there is more to it than simply one is better than the other. K03 and K04 engines exhibit different boost behaviours for starters (no one ever says what engine they've got) and it also depends on the overall health of the engine, and if it's leaking boost etc, state of tune etc.
I had a GFB in my ED30 with a custom map and it felt better off boost, more responsive, but we're not talking a night/day difference here, very subtle.
Since switching to Revo, I notice zero difference between a Rev G and DV+. In actual fact, with this tune it actually feels best with a Rev D, which internet folklore haves you believe is 'designed to leak', but I've never had any problems with the D.
I did have a serious issue with the DV+ though, which I raised with Go Fast Bits. The orange silicon pad detached itself from the brass piston. I lost faith in the product after that and have stuck with OEM DVs ever since.
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Atm I’m having running issues with my mk6 golf gti.
I’ve been told they reckon it’s my gfb valve sticking, once weather warms out swapping it for a rev g to see if it solves the problem. It started shortly after going stage 2
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When I was at Racingline HQs recently, they mentioned the same thing, so they don’t use them anymore either.
My suspicion is the brass piston and alloy housing expand at different rates, so I can see how that would cause binding. Take apart a well used one and you can see scoring marks on the piston, which hints at metal on metal contact, despite lubing the piston liberally with engine oil.
I like the design and concept of the DV+ but I think on the K03 especially, they don’t like the heat.
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Funny you say that because my car starts playing up when it’s up to temperature.
Something that will be getting swapped out very soon to see if it solves the problem.
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It needs improving really. Perhaps a composite plastic piston with the rubber pad, instead of brass. Another thing about the DV+, it only has 1 hole in the piston to generate negative pressure (to pull the piston down harder to seal it), whereas Rev G and D both have 4 holes, so more pulls down with more force.
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I installed a new Rev G and then a year later there was a noticeable loss of power again so replaced with a GFB DV+ which has been excellent ever since
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I've been on a rev G for a couple of years running Stage 2 levels of boost (k03) and it's still all good as far as the seat of the pants-ometer can tell. I was thinking of trying a GFB valve after all the good reports about improved response but there are now enough negative stories to make me think twice.
It could be that my rev G is indeed past its best and I've not noticed as it's been a gradual loss of boost, but it's fared really well as far as I can tell.
It's going in to Statller for a few bits soon so I'll get a new rev G in there while it's there for peace of mind. I'm just not quite convinced the GFB is really all that!
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It needs improving really. Perhaps a composite plastic piston with the rubber pad, instead of brass. Another thing about the DV+, it only has 1 hole in the piston to generate negative pressure (to pull the piston down harder to seal it), whereas Rev G and D both have 4 holes, so more pulls down with more force.
Following what the DV+ developer explained, I think the only hole is enough to make the boost pressure relief. Right?
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The hole is to force the piston down off boost to create a gas tight seal. The spring pressure alone is nowhere near enough to push the piston down on part throttle. A light spring is needed for rapid pressure relief when you back off the accelerator.
What I'm saying is the DV+ only has one hole, but OEM uses 4 holes. Make of that what you will, but to me, any deviation away from the OEM design introduces a variable which makes troubleshooting a pain in the neck.