What a difference a new set of volvo plugs make

[gazO2V40T4]

Next job coil packs as they are cracked just a quick fix for now loads of insulation tape works a treat will order coil packs Monday

[S40 Volvo]

Originally Posted by Alex121

Yep, everyone has always said it.

Always use genuine!

ALWAYS

Couldn't agree more!

[kieran40]

hahaa gaz i also cut my teeth on ford engines building zvh units in the garden shed memories also dropping 1.8 k series in rover metro's lol,good fun but carnt be assed with the agg ive become mr sensible bought a volvo and never looked back.made me lazy owning a volvo thou only time the bonnets up and the tools come out is for servicing lol.

[gazO2V40T4]

You can't beat a good old ford for a bit of tinkering but unfortunately so far the only thing I have done with this t4 is open the bonnet and get the tools out the guy that owned it before probably never even used the bonnet pull once but never mind I will sort it !!

Once it's all sorted I will tax it and then I can think about a few mods maybe the only one I have done so far is fitting a forge dump valve and blanking plate as I picked it up for a bargain (£20) and it's quite when your just tootling round almost silent but then when you hit the loud pedal you get a nice tish the inner child in me has a little grin

[Alex121]

I get that sound without an after market dump valve lol. The foam around my air filter is still there, nothing as far as I can see has been changed at all. I'm lucky in the sense that my T4 gives me the blow off noise without fitting after market stuff.

Btw if you do a search you'll see these cars don't really get on with dump valves...They're good cars but they aren't half fussy the T4s as you've found out with your spark plugs!

[gazO2V40T4]

The noise your probably getting will be waste gate chatter
I only bought the dump valve because it was going cheap and as long as you fit a dual piston type the car can live with it and if it starts to give me hassle it will be my excuse for buying a forge recirc valve instead

[960kg]

I know it`s not the point here.....but in the end or well, the beginning, it does depend what one is after ...more noise as it seems to go faster or just plain better performance.

With a dump valve on a near standard motor the lag will be more from the turbo because the boost has been wasted completely to the atmosphere but with the standard setup the dump valve, recirculating valve, in the turbo keeps some boost to keep the turbo spinning rapidly so all ready for WOT without lag...

Some run with just a blanking plate and no blow off valve, over time this can damage the turbo, it stalls the compressor turbo between gearchanges and so will accelerate a lot less but the noise of course makes you think it`s flying!

The tsh tsh noise is not wastegate chatter as there is no such thing, it is compressor surge.

Just trying to help!

[gazO2V40T4]

960kg as stated in previous posts the dump valve was purchased as it was very cheap £20 forge item my intention is to modify the car and fit the forge recirc valve but for now the dump valve is there just for a little grin factor

And yes you are right the noise is compressor surge but commonly known as waste gate chatter it gives more of a churp than a tish

Anyway as far as boost goes I am not quite sure if it is running standard boost because it gives such a mighty kick in the backside when it comes in at 2750rpm and keeps pulling strong all the way to the redline my next point of call will be to fit new coil packs and the fuel filter I have for it then I will purchase a boost gauge so I can see what the turbo is doing

PS would you kindly tell what "WOT" actually means ????

[960kg]

Originally Posted by gazO2V40T4

And yes you are right the noise is compressor surge but commonly known as waste gate chatter it gives more of a churp than a tish


PS would you kindly tell what "WOT" actually means ????

WOT is what Volvo call in there literature "Wide Open Throttle"

Not arguing at all just trying to help but the wastegate is on the other side of the turbo, as you know, and it is shut or open it does not flutter or chatter.

Wastegate Chatter if there was such a name cannot be called Compressor Surge as this relates to the Compressor Wheel that spins for the boost which is a completely different mechanical part. This is the noise you hear on Rally Cars which use turbos.

[gazO2V40T4]

I also do not want to have an argument a lot of people refer to the rally car noise as waste gate chatter but I am not suggesting that it is the correct name for it just that a lot of people call it that and now it as that I think you should make it your business to attend all the cruises and educate these people