Engine 'over revs' in 4th, 5th & 6th...

[Russ.C]

Hi all, haven't posted on here for ages but got a bit of a problem I could do with diagnosing!
I've got an ED30 with Bluefin, no other mods, shes on 20k.
For the last couple of months when I accelerate hard in 4th, 5th & 6th at about 2.5k revs - basically where the turbo boost kicks in, the rev counter kind of 'jumps' up to about 4.5k then comes down a bit and settles into its normal smooth climb, its hard to explain but it feels kind of like its wheel spinning and then finds grip and its ok, but its not.  When it does this you can hear the engine rev up quickly, then drop down again.  Actual acceleration doesn't seem affected.
It doesn't do it at all in 1st, 2nd or 3rd.  As most of your will know, 3rd is where you get the greatest pull from a remapped ED30, and it pulls fine with no hint of the problem I experience in 4th 5th and 6th.
It also does it at high speeds like when your in 6th at about 80mph and floor it.
All seems a bit strange, I'm wondering if the gearbox is fooked?  Not very technically minded but if it was then wouldn't I have the same problem with all the gears, not just the top three? 
It started as I say a few months ago during the bad weather (snow etc.) but at the time I drove very carefully as the roads were so slippy, so when it happened I assumed it was just wheel spin, but as the roads have dried I have noticed it more.  It doesn't seem to have got any worse, which is why I haven't really done anything about it yet.  Thanks for taking the time to read this! 

[R32UK]

If its remapped then I would have thought the first port of call would have been blufin... They will probably be able to give a diagnostic

[chungster]

first sign of clutch slip i say!

[bacillus]

first sign of clutch slip i say!

X2

[Russ.C]

first sign of clutch slip i say!

Thanks for the replies. I didnt mention in my first post, but when I uninstall the Bluefin and return it to standard its fine in all gears with no sign of any problems.
If it was the clutch slipping wouldn't I experience the problem even in stock mode?
Thanks again.  Russ

[winrya]

No its the extra torque of the remap that is pushing the limits of the clutch.  I'd say defo clutch slip

[bacillus]

It's the higher torque with the BF map installed that causes it to slip. The fact that it's ok with the stock map is futher evidence that it's a clutch slip issue.

[nige_s]

if you find it worse on a steep incline, its defo clutch.

[Russ.C]

Ok thanks.  So if it is the clutch whats the best way to go about, if I returned it to stock and took it to the dealer and complain about it slipping is it likely to be warranty? If they test drive it in stock it wont show them the problem, but equally if I tell them I run it on a remap they might just blame it on that and make me pay for a new one. (how much would a new clutch cost by the way?) thanks? Russ

[winrya]

They wont replace the clutch without feeling the slip.  I'd be tempted to take them for a spin with the map on.  VW have no way of detecting a remap.  Without a rolling road it would be difficult for them to claim its remapped.

From what i can gather uprated clutches are £500.  Not sure if that includes fitting?