Couple of questions....Dyno plots & KO4 compressor surge

[flashp]

It may be because I haven't looked closely enough through this area of the forum but I haven't many (any) Dyno plots for R-Tech tuned vehicles. Is there any to see here?

Next question...the KO4 equipped cars are known for a phenomena known as compressor surge. Does this custom mapping eliminate this?

Thanks. 

[greygti]

Niki/Rtech is the best in the business, and very good at mapping compressor surge out

[flashp]

I also hear that a Rev D DV can eliminate this.
They certainly have lot's of positive reviews, can't argue with that!

I'm currently using Revo and have been happy with it apart from this compressor surge issue.

[xjay1337]

It's pure mapping to work around, not using a dv.
niki will tell you stick with a G valve 

[flashp]

Maybe he'll reply here???

[flashp]

It's pure mapping to work around, not using a dv.
niki will tell you stick with a G valve 

Cheers, I'll give them a ring or send an email tomorrow and see what he says.

[DANBOY66]

look on my build thread i have k04 dyno plots and now i have the new k04 anti surge turbo i have posted a graph for that as well

tuned at r-tech

its the blue vw badge under my name to find my build thread 

[Dan_FR]

Surge is simply bringing in the boost too strong and too early with the K04. All you can do is reduce the boost around the surge point to minimise it as much as possible without sacrificing too much performance. A Rev D will have no effect on this other than leak boost.

[flashp]

look on my build thread i have k04 dyno plots and now i have the new k04 anti surge turbo i have posted a graph for that as well

tuned at r-tech

its the blue vw badge under my name to find my build thread 

Thanks for that, a good read!
Do you happen to know what specifically was done to the turbo to alleviate the problem?

[flashp]

Surge is simply bringing in the boost too strong and too early with the K04. All you can do is reduce the boost around the surge point to minimise it as much as possible without sacrificing too much performance. A Rev D will have no effect on this other than leak boost.

I can understand this an an explanation. I found a fairly convincing video on YouTube where this gent in America says that he had this issue with his Mk5 which was also tuned by APR. He says that between APR and VW it was determined that the RevD valve better suits this application through being a piston type of valve. His video where he demonstrates the the problem being solved clearly shows the absence of surge as well as the the chirping noise.

If it does work maybe it's the fact that it bleeds off boost that it does?

I don't know enough about this but I know I don't like it and that there is a reason for it and I also want it gone.

If it means a custom map from R Tech then so be it but they're a good distance from me so trying a DV first appeals to me but I can see that it could possibly be a waste of money, albeit a relatively small sum.

Thanks for your input though, it's appreciated! 

[Dan_FR]

Do you mean surge on boost under WOT, or the surge type flutter noise that K04's get on lift off (which sounds awesome)

I'm referring to the surging flutter noise you get under WOT with lots of boost below 4k rpm, where the valve should make no difference at all as it should be sealed/shut

No mapping will change the way the DV sounds on lift off, it'll be caused by a combination of the long thin pipes and the DV not releasing enough air pressure quickly enough. I can fully understand a Rev D reducing it, as if you look at the design of the G vs the D, once the D opens it will be able to flow a much larger volume of air which will reduce this noise.

[flashp]

Do you mean surge on boost under WOT, or the surge type flutter noise that K04's get on lift off (which sounds awesome)

I'm referring to the surging flutter noise you get under WOT with lots of boost below 4k rpm, where the valve should make no difference at all as it should be sealed/shut

No mapping will change the way the DV sounds on lift off, it'll be caused by a combination of the long thin pipes and the DV not releasing enough air pressure quickly enough. I can fully understand a Rev D reducing it, as if you look at the design of the G vs the D, once the D opens it will be able to flow a much larger volume of air which will reduce this noise.

The best way I can describe it is if you're driving at say 2500rpm or thereabouts in 6th gear and you accelerate hard you hear a 'chuffing' noise (not the flutter) and it feels like the car is bogged down until sufficient revs can be developed and it clears. If you drop a couple gears there's no issue at all. This noise isn't that which is made by lifting off.

[flashp]

Just checked with JKM and they confirm that I had a rev D valve in 2013 which was about 11,000 ago. So that kind of indicates what I need to do now then. I'll be giving R-Tech a ring to see what he says.

[DANBOY66]

on my new turbo the cold size wheel has been changed i think its a lightweight wheel that has an extra blade 
i have also had the hot side wheel clipped to aid better flow at the top end
with up rated bearing and seals

as previously said r-tech can't eliminate it but he can map around it

on my car i had a super chips map and it was mapped straight through it the cha cha cha went on forever before finally shutting up
after my first r-tech map it literally done it 3 times with bigger gaps in beetween before it was totaly gone

on Facebook beach buggy turbos a better description and pictures of my turbo 

[GrayMK5GTI]

@flashp Niki maps around the compresser surge @MC71 mentioned after his Stage 2+ map that surge is only noticeable under a lot of load in a high gear (like foot to floor in 6th gear at low revs).

My mates REVO'd K1 with EVOMS intake is awful for surge in every gear, and the Dyno graph shows the drop in power as the turbo surges

Some graphs in here on Surrey RR's heartbreaker: http://www.mk5golfgti.co.uk/forum/index.php/topic,93698.0.html

Niki's traction control mapping makes a huge difference to getting power down, and the switchable mapping is also free