tomfromthenorth

I don't know the perfect terminology for these things, I thought stall was misleading because it makes people think that you are stopping your turbo when you're just slowing it down a bit, and chopping up some air going backwards down a one way pipe. it's just we call it compressor surge when it happens on a Sea King engine. And when it does it's like that video above of "true" compressor surge. People also call the same noise (surge) wastegate chatter don't they, but waste gates don't make any sound do they? Unless you have a screamer pipe which I understand to be tapped off exhaust gas that normally just bypasses the power turbine and re enters the exhaust behind it, but in the case of a screamer pipe shrieks out to atmosphere? Which isn't really wastegate noise either just something vaguely associated with the wastegate. And when you shut a Gnome engine down you get the ultimate Scania Air brakes noise :lol:

Mine are probably louder because: I have increased boost. 2.5 inch hard pipes. Split intake. 2 Cone filters. The recircs are really high up probably more audible if they make any whooshes (which although they shouldn't they're still moving compressed air through pipes.) BDE GHKs which are causing some surge. An exhaust that doesn't mask it with BOOM! So you aren't guaranteed this vvvv from the GHKs And mine sounds more like a "Pow!" sound than that Quattro.

My nose isn't out of joint :) I thought the air brake sound clip came after my post and just thought "haha, the one part of my car that isn't against the code of OEM+ Funky Si modifying."

Try stock recircs first, and if they make a noise like blowing over a milk bottle too then get the BDEs :) otherwise save the 60 quid or whatever they were. Apart from the bloody howling resonant honk the stock recircs drove really well too.

The boss has let me practice for TOTB on the taxiway behind the hangar. You can just hear it on the first gear change. In real life its clearly audible. But look at the responsiveness and how smooth it is. Going down the runway at work.: http://youtu.be/IR229dZKq88

Its not one of those multiple second "wha-ch-ch-ch-ch..." type flutters. Its more like a squeaky sneeze. I'd have to pay closer attention but it does it most noticeably at 16psi and a bit at any positive boost pressure below that. It must be so stiff that even at 16 psi it doesn't fully open the recirc valve. But even if that's because Mark somehow put them together wrong, I wouldn't have it any other way, it runs beautifully.

My turbos are going to die of being at 16psi long before they die of the surge. But both of these things make me grin till it hurts, a small price to pay. You are totally right but I think it would take a lot of miles to do it. Noz uses a full closed system, because it sounds ace :biggrin:

Si, I know you have said before that dump valves sound like a scania's air brakes, I have recircs, I bought the kit to get rid of the goose honk and an unexpected side effect is surge. I Can't do right for doing wrong haha I thought it would be the one part of my car you would approve of!

I promise mine give a bit of compressor surge. They go Kssssk-chirrup. They are now not recircing all the air, some of it just goes back through the turbo blades and surges and makes a noise like throwing a budgie through an office fan. Mark, mondo, Dave back me up :lol:

http://bde-performance.com/goose.htm Those

Xtd might be ok, competition clutch will be better than ok.

In theory if you vent any air at all it will run rich. Some people's cars seem to get away with it, mine didn't at all. It wouldnt even idle unless you had the air con on. Recircs all the way, I have the BDE goose killers and they sound awesome. "Kssssk-chirrup" like a Quattro.

I have to say it, I got one, total waste of money, it slipped and slipped and slipped. I kept the flywheel but had to change it for a competition clutch, that is absolutely awesome and totally possible to drive slowly in traffic, I cant speak for other 6 pucks, but the CC one is silent, strong, and smooth to engage.

This is my car on a zedworld chip and similar mods to yours. this is it after nothing more than a noz map

pm noz mate, he is the guru, but I bet that car is totally fine and the figures are wrong, or he set the air pressure (atmospheric) wrong or there was a dead crow under the rollers or something. I think a boost leak is unlikely with that steady peak boost. I am prepared to eat humble pie, but I hope for you and the car's sake that I am right.

Anyway, never mind any of this, does it feel fast, if the answer is yes, scrumple that bloody graph up :thumbup1:

How could it be so smooth and healthy looking but down 50hp??? I'm not saying that it isn't the case but seems strange?

Mate that looks a good graph to me, really smooth and making stock power. You are lucky your jets are giving you that boost, mine gave me 21 psi that I didn't discover 'till about 1500 miles later when I fitted an after market boost gauge that went higher than the stock one. I immediately fitted an electronic boost controller to lower it and it ran a lot better. A generic chip will never be as good as a rolling road session. My rolling road session was cheaper than the jets and chip that gave me 21 psi then 330hp after I reduced the boost to 14psi with ebc. But that aside that looks a lovely smooth power curve and I assume its RWHP.

I know what you mean, paralax error is what it's called, I am afraid I dont know but I imagine it's square on with you having to compensate for the error "by eye like" :)

I did drive it today and had a right wrestle in the wet after this heat we have had. I left a 40 zone in third and applied 3mm of throttle (2mm too much) and the car sneezed :lol:! I would love to have seen it from the point of view of the oncoming Merc because within half a second the car shook it's hips and I got turbo flutter and a pair of fireballs. It revs like a flymo hedge strimmer these days, realising that I was driving with a grip level that is more commonly associated with snow, I very carefully cracked the throttle again around a long radius bend, with the steering wheel dead straight and the normal hasty prayer of "I-hope-I'm-as-good-as-I-think-I-am!" :sweatdrop: I managed to keep just the inside wheel spinning about +3mph for 100m praying that I had correctly judged the bite point of my viscous and that it wasn't about to take the other wheel with it haha! Anyway, that's not what I was going to say, I have worked out how I am getting to TOTB. I come off a 24 hour shift on the Saturday morning of TOTB. I was going to just hammer down for the sunday but the car could do with a Noz map on the Saturday. So, the plan is to get the car to my cousin in Bishop Auckland some time before hand and get a train back to work. Then he will drive down to get it mapped on the Saturday at the same time that I leave work and get on my ZX10-R and head south. I will meet my ex girlfriend who will drive me the rest of the way in her Mazda 2 to meet Adam and you guys before we all stay in a hotel. Then Race to victory convoy home winner :biggrin:

It might be that un metered air problem, but could also be knackered if second hand and leaking or not doing what they should be inside. I reckon a map could make it better but I don't think you can ever totally sort the problem unless you moved the MAF/s nearer to the throttle bodies.

My heart was beating watching that. I really felt for his wife having to panic for even a just few seconds longer than necessary.

Hey man, that pricked my ears up because that is exactly my build brief to myself, "supercar" not "track/racecar". Welcome to the club and of course PICTURES! :biggrin:

Gary, you are the man :thumbup: :bow:

I just think the plate can hide a bit atm, being a short reg. and legally petite or whatever size it is. White surrounded by white, it's been discussed before but plates are difficult on the front of zeds, black would highlight it.