My Divided Manifold Quick Spool Valve

[V8KILR]

Toyota used ceramics in the stock TT exhaust gas diverter valve, they probably found two metals were prone to sticking or seizing. Anything that close to the ports will be subject to a horrendously hostile environment. Nicely made, but what detriment will the fairly significant restriction have, even when open?

 

Sorry I missed your post at the time. The dyno graph shows a power reduction but I believe that is all due to the converter change. Shame I didn't get a dyno graph before changing the converter.

 

I think that as long as the wastegate is still bleeding off some exhaust gas at full power then there should be more then enough exhaust gas to spin the turbo as fast as it is needed, so supplying the same amount of air to the engine. Also if the wastegate is not 100% open at full power, then there should be enough exhaust flow out the wastegate to stop any exhaust restriction occurring. I run a 60mm wastegate.

 

My tuner says he didn't change the wastegate settings at all and its holding exactly the same boost psi as before, so in conclusion I don't think the restriction caused by the valve is having any detrimental effect on the power.

 

I'm using a 0.84 AR exhaust housing (both before and after the QSV install) and I have a 1.00 AR housing that I can swap to if I feel it will help in the future. As power keeps climbing all the way to the 8500rpm redline, I think its all good at the moment.

Edited October 8, 2013 by V8KILR (see edit history)

[Chris Wilson]

No worries, glad it's working well for you. I would worry about heat on the diaphragm material in the actuator. Toyota mounted the actuator for the EGCV well away from the major heat source on a LOOOONG bracket. I believe you can get actuators with Kevlar diaphragms if heat is an issue, but have never tried them,

[V8KILR]

I'll be giving it a good testing this coming summer in NZ with lots of drag racing and road trips.

 

The downpipe is wrapped and the actuator is a genuine Garrett item with their high temp diaphram in it so hopefully it will be okay. If it fails, I do have a spare actuator and I'll get a heat shield made for it if the first one fails.

[Pulley]

Great job!

I have run a very similar setup myself only using a servo to control the valve

I ended up using ceramic to overcome temp issues

I originally built my valve into my custom manifold, then opted to make it a separate flange as you have for servicing

I drive my valve from my boost controller

 

How balanced is the manifold restriction across your manifold?

I have a balanced set of runners feeding a small chamber pre turbo so have no uneven pressure with my valve fully closed

I see you have an angular valve so probably have no issues

 

Great engineering!

[V8KILR]

Great job!

I have run a very similar setup myself only using a servo to control the valve

I ended up using ceramic to overcome temp issues

I originally built my valve into my custom manifold, then opted to make it a separate flange as you have for servicing

I drive my valve from my boost controller

 

How balanced is the manifold restriction across your manifold?

I have a balanced set of runners feeding a small chamber pre turbo so have no uneven pressure with my valve fully closed

I see you have an angular valve so probably have no issues

 

Great engineering!

 

Thanks, it's great to see someone else doing their own QSV setup. Do you have any pics?

 

The side of the manifold that gets blocked off by the QSV can balance pressure with the other side through my wastegate pipe if the 20mm gap is too restrictive. Based on that I'm fairly sure the pressure on each side will be close to even. This pic shows how easily the exhaust gas can flow from one side to the other.