RECIRCULATION VALVE - dump valve whats the difference?

What size do I need to get? I'm getting bored of my dump valve now.

 

I didn't do any of the mods on mine, it had the blanking plate fitted when I bought it. It was done in 2012 as I spoke to the guy who used to own it so I reckon it's done around 10-12k miles since then.

I wouldn't say there is any lag at all compared to my old 225 with forge dump valve, if there is we're talking non-noticeable differences.

 

Il be honest mate, I had a skyline r33 running at 407bhp and had a similar set up (didnt need a blanking plate) and it was running very high levels of boost and it used the flutter, "turbo stall" and never had any problems with it. This was a T38 turbine, that had huge amounts of air going through it. I was told by the guy who set the new turbo up that there were virtually no difference between venting/blanking, unless your drifting the car and constantly high boost. Personally I cant see it having much effect of the turbo.

Its everyones own choice though at the end of the day.


Also cheers for the video Rob, will order the pipe next week, sick of that damn wooosh'ing noise!

 

Hey mate what did you with the wee red hose coming out of the dump valve??

 

Just remove it and blank it off at the other end mate.

 

What did you blank it off with? Theres a wee T piece but have no idea what size it is

Cheers mate

 

It was already done when I got the car, but it looks like a small tight fitting screw or bolt.

 

One downside to the dump valve - it gets in the way of the thermostat costing you an extra five minutes when you change it.

 

Good man. I had thought about doing that but wasnt too sure. Have a screw that would be a good tight fit, will try it out tomorrow.

Cheers!

 

Take dump valve off. Eather get new hose or cut a bit of brush handle and stick it in. With the vacum end where it goes to a t peace eather get a straight peace or snip some hose fold it and put a cable tie on so it's blanked if Udont have brush handle or tht u can keep the dump valve in place and just remove vac pipe from the top then the dump valve won't do anything

 

Be careful. I used a screw and it came out whilst I was driving!

 

Either dump valve or recirc valve will vent the unnececery pressure out and allow the turbo to spool up faster as it doesnt need to overcome the built up pressure in front of it. A recirc has a benefit of being more quiet but more importantly doesnt waste the air tottaly. Ie doesnt have to collect all the air from the filter + higher pressure in the intake to the turbo for more efort less spool up.

 

But on the downside a recirc valve will divert hot air into the air filter, it also has limitations on how much boost it can divert depending on boost levels, whether this affects highly tuned megs or not I don't know.

 

So just fitting a blanking plate will give a loud chatter noise then?

 

Yes mate.

 

Does anyone kniw the size vacum pipe i need to buy is it 4mm?

 

But having it you will lose performance 100% and that cant bee shown on the dyno we are usually using. You can only feal it.

And why do some of you "like" the chater noise? When it is a noise of something that is not operating correctly. That is like someone is liking the "knock" sound...

 

Not true the car still has most of its original boost pressure at the same revs, spool up time is slower due to the pressure being forced back over the blades but this time is in milliseconds. I've tried all three methods and the difference on the road is negligible on the std engine
yes mate it's 4mm I/d vacuum hose