Can you get the waste gate or dump valve or whatever it is that makes the bouncing noise when you come off the throttle short of boosting the tits off the car?

I've had a HKS blow off, but it kept dropping the boost level as it was atmospheric so I got rid of that.

Its bugging me as I've been looking at a Forge SPLT-R valve and wondered if it would work, the car is running a phase 1 map (210ish) with blueflame cat back if that makes any difference (and a CAI can be added if that is needed).

Ta

You mean the Pschhhhh noise when you lift off?

Get a CAI and a Forge or Bailey diverter valve and you will get a lot louder noise.

Nah, its the chattering or bouncing noise, can only describe it as: "tss tss tss tss tss" as you lift off, not the normal pssssst noise from the dump/recirc valve.

Kinda hard to explain, I had an Escort Cossie and even at low boost it used to chatter like mad when I lifted off.

Thats 'wastegate stall' isnt it causing the air to go back through the compressor blades...

Isn't the Cossie sound because it has a different sort of turbo?

It could well be,

I've got two T4 turbos sat in my garage begging for use, but I don't think 132k miles and a standard 1.8T block would take 2 bar of boost!!!!

I heard a passat the other night with the chattering noise, looked a bit of a sleeper with S3 rims and slammed to the deck.

Thats 'wastegate stall' isnt it causing the air to go back through the compressor blades...

I don't think it's all that healthy either iirc

No, I forgot to mention that...

Might explain why my Cossie had receipts for about 5 recon turbos then before I bought it.

In that case I think I'll just have to make do with the SPLT-R valve.

Compressor Stall.

You can get it on the Octy, but I'm unsure as to how the K03s will react to it.

The ECU is also expecting the boost to be recirculated back into the inlet.

You need to blank off the diverter valve holes and IIRC you need to bypass the N249 valve.

I dont know how loud the "chatter" would be.

Rob - wanna sell me a T4? LOL

Oh how simple cossies are - My old one used to "chatter" nicely. I had it on a T3 and a T34, and my turbo's where fine!

Hi, Ive got a SPLTR valve and all is good, however, you wont get the flutter.

I think the flutter noise is actually the piston in the dump valve bouncing. The last cosworth owner I knew had this start to happen when it was running 25+ psi... This was the general consensus then anyway...

Cheers

Rob

Compressor Stall.

You can get it on the Octy, but I'm unsure as to how the K03s will react to it.

The ECU is also expecting the boost to be recirculated back into the inlet.

You need to blank off the diverter valve holes and IIRC you need to bypass the N249 valve.

I dont know how loud the "chatter" would be.

Rob - wanna sell me a T4? LOL

Oh how simple cossies are - My old one used to "chatter" nicely. I had it on a T3 and a T34, and my turbo's where fine!

Hi, Ive got a SPLTR valve and all is good, however, you wont get the flutter.

I think the flutter noise is actually the piston in the dump valve bouncing. The last cosworth owner I knew had this start to happen when it was running 25+ psi... This was the general consensus then anyway...

Cheers

Rob

I've always understood it as compresser stall as well and rally teams have mega money with which buy many turbos when they die an early death. I may be wrong though

World Rally Cars run alot of boost on small turbo's.

this will cause them to break often lol.

Compressor Stall is also known as surge. The turbo is making boost but the engine cannot consume the air, so the compressor blades are chopping up the air.

A dump valve piston chattering is not going to be audible over the engine, so it wont be that.

Using the blanking plug provided the Splt-r valve does chatter when set to fully atmospheric. But expect a drop in performance, Hence the reason i changed mine back to 50/50

The only reason you'd suffer performance drop is if the charge air is being fed to atmosphere BEFORE being consumed by the engine.

Sorry i shouldnt have said "expect", But im sure i had a drop in performance, Also the car was struggling to idle. Think i'll stick to the theory "never get a fully Atmospheric DV on a 1.8T!"

Also Mike, Thats the reason i never got back to you regarding your VAGCOM, Just changed the SPLT-R valve settings. seems to have fixed it. Thanks for the offer though

Darren

Hi Darren,

Glad you sorted it.

If you fit a CAI kit you will get a tssssch like on my car.

Mike.

PM.

sure you dont want one of these instead :rofl:

Saber EDV V2 Non-Turbo Electronic Dump Valve Universal on eBay, also, Other Car Tuning, Car Tuning Styling, Cars, Parts Vehicles (end time 14-Feb-08 21:53:51 GMT)

Actually i can get a 2 tone effect from my "proper" DV with a bit of carefull throttle control.

sure you dont want one of these instead :rofl:

Saber EDV V2 Non-Turbo Electronic Dump Valve Universal on eBay, also, Other Car Tuning, Car Tuning Styling, Cars, Parts Vehicles (end time 14-Feb-08 21:53:51 GMT)

Actually i can get a 2 tone effect from my "proper" DV with a bit of carefull throttle control.

There's a Fast and the Furious style clio going round by my office with one of these its sounds like a bus pulling up when it changes gear. I do laugh when I hear it

There's a Fast and the Furious style clio going round by my office with one of these its sounds like a bus pulling up when it changes gear. I do laugh when I hear it

yep no spool up noise just faaassssssssssss

there's a couple of Corsas over by with one on i'm sure, didnt sound right...sounded more like a bowel movement than wastegate

sure you dont want one of these instead :rofl:

Saber EDV V2 Non-Turbo Electronic Dump Valve Universal on eBay, also, Other Car Tuning, Car Tuning Styling, Cars, Parts Vehicles (end time 14-Feb-08 21:53:51 GMT)

Actually i can get a 2 tone effect from my "proper" DV with a bit of carefull throttle control.

Don't do it,you will have all the old dears stepping out into the road ,thinking ther bus has pulled up.lol

YouTube - Fake Dump Valve

Darren,

Replied.

Don't do it,you will have all the old dears stepping out into the road ,thinking ther bus has pulled up.lol

YouTube - Fake Dump Valve

OMG thats the same style as the Clio and just as much a piece of 5hit

Compressor Stall.

You can get it on the Octy, but I'm unsure as to how the K03s will react to it.

The ECU is also expecting the boost to be recirculated back into the inlet.

You need to blank off the diverter valve holes and IIRC you need to bypass the N249 valve.

I dont know how loud the "chatter" would be.

Rob - wanna sell me a T4? LOL

Oh how simple cossies are - My old one used to "chatter" nicely. I had it on a T3 and a T34, and my turbo's where fine!

I'm presuming a custom map would be in order to map around the N249?

A mate of mine has a TT and he has had the N75 mapped out of the system and it is just unplugged from the electrical circuit.

Oh and I'm saving the T4's for when I "stumble" upon an 8 injector plenum and wiring loom for a Cossie, or to just destroy a Sierra 4x4 engine for a laugh lol.