GFB.Com DV+ Diverter Valve Review For 2017 QX30 By Luis Cotto
Today I will be reviewing the GFB.com DV+ Diverter Valve T9358 Upgrade Kit, as I like to call it. After my last review regarding a spacer that could be placed in front of the QX30’s factory diverter, my inbox was filled with people asking me all kinds of questions. Many people asked things such as “How did this affect the car?, Did you notice any drawbacks or performance gains?, Did you find anything else I could do to my car?”. Naturally this did pluck a cord in my brain, making me wonder what else is out there for this car? After some research I stumbled onto GFB.com, an Australian company that offers the DV+. This ingenious solution replaces and also adds new components to the factory diverter valve improving performance. Just like my other reviews I will talk about three main points: build quality and a brief explanation of how the part works, the installation experience, and lastly I will describe the changes to the car’s performance. I will conclude the review with a summery, and finally talk about whether or not you should consider buying this part for yourself.
The GFB DV+ T9358 Diverter Valve, is not really a full diverter valve. It is a set of components that will be joined with factory parts that function together acting as a new upgraded diverter valve. The components you will find in this kit are a main housing that's made of a solid piece of billet aluminum, two heavy duty springs, a new plunger, an upgraded piston, and lastly a set up lengthened stainless steel screws to hold it all together. Immediately every part looks and feels great, the housing is flawless and fits very tight. The large spring in this kit is a totally new part, while the second spring is a replacement to the factory spring. To compare the two spring I will put it like this. The new spring is actually very substantial, and has real resistance to it, while the factory spring looks and feels like a pen spring. The plunger in some sense is also a new component. Yes the factory setup has a plunger of sorts, but truly they do not compare at all. Now the most noticeable piece is the piston. It’s miles ahead in superiority when placed next to the factory piston. It's made of what looks to be brass, with a silicon front face, with a single hole in the center. The factory piston on the other hand is all plastic with many holes on the inside.
Though my understanding of how the DV+ work is basic, I will do my best to explain it and try to keep it simple. The overall working of the DV+ truly is ingenious. To me there are two main parts of this kit that really stand out. One being the ability of this kit to allow the valve to work essentially the way it originally intended to, but with the replacement of some components of the factory valve; the diverter will have a substantial increase in efficiency. Secondly, to me the most noticeable change is the highly upgraded piston. With its clever single hole design, boot pressure can build on the face of the piston, while the hole in the center allows air to enter the backside of the piston. This creates an equalization of forces, so the piston now has pressure on the front of its face, and also on the back, essentially canceling out.
With the piston design allowing pressures equalization, this means to some extent you can have 4 lbs of boost on the piston or 40 lbs of boost on the piston, with essentially no chance of the piston moving or boost leaking. As an added bonus the kit also brings a large spring that is added directly behind the piston. The spring allows the piston to move pneumatically . Unlike the factory setup where the valve is fully open or closed by the ECU, this spring allows the valve to open just the amount needed. This means you can handle instances when just a bit of excess boost is built that needs to be vented but at the same maintaining some boost pressure. The spring will allow just the extra boost to escape without fully dumping all of the pressure in the system. In turn you won't need to rebuild boot pressure, so when you get back on the throttle you should have immediate power and much less lag.
Installation is very straightforward and simple. From the time I removed the factory diverter, replaced the components, and reinstalled everything, it had been under 15 minutes. The process starts with removing the decorative engine top cover. This is done by pulling the cover straight up by the corner closest to the driver side headlight. Once the tab on that corner pops free repeat this to every corner of the cover. After the lids off, you will be able to see the diverter and its three M6 bolts. Remove the one plug connected divertor, then remove the three bolts holding the divertor in place with an allen tool. Set your divertor down and remove the plunger by giving it a gentle twist. Once it comes free carefully separate the parts. There is a spring inside of the divertor. If you plan to keep the OEM parts be careful not to loose the spring, it tends to fly out. With all the factory internals removed start by placing the new revamped spring down the divertor, then place the DV+ plunger on top of this. Enclose these two parts with the DV+ main housing, the fit is tight but don’t give up. From here all there is left to do is place the new large spring into the housing. Place some oil over the brass plunger and cover the large spring with it. Place your newly upgraded diverter valve back in the car, and don't forget to use the new longer bolts, and also to reattach the removed plug.
Once you get everything bolted back up, this is where the fun begins. Give your car a few good revs and you will notice a different sound coming from under the hood. It's hard to describe, it's not the sound you get from atmospheric venting. The sound is more of a quick whistle. It is very pleasing and unique to, say the least. Once I was done enjoying the subtle sound change, I took the car to the street. I noticed something fairly quickly, the factory QX30 does have some very substantial acceleration lag, but all of a sudden it wasn't nearly as bad. Could I be dreaming, or was my brain playing tricks on me? Well after a month of driving the car, I confirmed that now the lag was finally tolerable. Does the car still have lag, sure it does but at least now it doesn't infuriate me.
The other major change I noticed after weeks of testing the DV+ is on long pulls the car does feel much better. I have really no way of proving it, but the between shifts the car seems to hold RPM up better than before. It's a bit crazy to say that this part could have caused so many changes, but it really did seem to improve quite a few things. Granted the changes are subtle, but there are a lot of them and together they make a nice difference. You're not going to add the DV+ to your car and all of a sudden have a 400hp QX30, but what you will have is the QX30 the way it should have been from the start. This mod makes the turbo setup on this car much more tolerable and a pleasure to drive. The days of feeling like a grandma accelerating from a red light finally seem to have come to an end for me.
I have been very pleased with the DV+. I have been driving with it on my car for over a month while writing this review. It has made my driving experience in the QX30 take a turn for the better. For a part that took me under 15 minutes to install, the changes you get from the car, while of course not world altering, are impressive. If someone today managed to pop my hood and removed this part from my car, I would without a doubt go out and get another tomorrow. I am very happy to have installed the DV+ before doing much else to my car. I feel it's a part anyone should have installed before doing most any other performance upgrades. It gets your car to the place it should have been from day one. So it's fairly clear at this point, should you go out and get one for yourself? Well if you ask me the answer is clearly yes.
Well everyone, it's been a slice. I Hope you enjoyed my review and video. I hope to see some videos of everyone else's cars and hear what you all have to say as well.