I don't know how many of you guys read/post on skylinesaustralia.com but this has been in development by Stao at hypergear turbos for a while. Simply amazing, he has been working on getting a VNT system reliable and cheap and while its still fairly expensive the results are pretty amazing. Bear in mind this is an RB25DET, with poncams and a massive turbocharger. If someone had the dosh to get him to retrofit VNT onto some 3076's that would be nuts When asked about lowmounting for VNT twins
Variable vein turbos arent new technology but the electronics behind making them work efficiently and effectively for our purposes requires allot of time and money. Its a fantastic idea which have great rewards should you get it right. But the down time in getting the combination correct far outweighs most peoples drive for power. For most its all too easy to buy off the shelf turbos and get it tuned for big numbers. Depending on the turbo manufacturer, some suffer from actuator failure more often then not, due to continuous movement in opperation. And these parts to replace arent exactly cheap. We use these style turbos at work, and we sell at least 1 actuator every few months. Albeit these turbos are probably running at near max efficiency most of the time. But the point of having to replace the actuator every season in some cases, becomes a bit of a joke. And these arent cheap turbo systems either. Regarding the use on a low mount manifold. This is where we could get stuck as they're not a small assembly in most instances. These are some pics of the style we use at work. They're huge. lol Anyways, always good to see peoples initiative taking over and producing some cool projects to better support everyone whom is into doing things a little different.
Not all VG turbo's have that electric controller hanging off the side, I've seen that style on the diesel Jeeps. The one on my Patrol is vacuum controlled and is quite compact. They are stout turbos as well, being a diesel mine spends half of its time pumping 20psi.
My diesel Missybitchy Challenger has the compact version too, no BOV needed which is a plus. Boost is controlled by the ECU which I'd like to interfere with because my auto is torque derated compared with a manual.
I bypassed my computer control with a Dawes and needle valve. The stock control on the Patrol is garbage boost is all over the shop.
Yep. One of the big trucks i drove had a big arsed Holset VGT and what looked like a wastegate can hanging of it. Nothing electrical. Looking at the graph my god that thing must hit like a hammer when it hits. However that never-ending spread of power after the initial clout is sweeeet!!! E
Just a little update, turns out the 465rwkw run was with VCT Disabled and they are having trouble getting it to work. Newest Dyno sheet, 27PSI, any more boost and ignition would break down.
I read on one of the Ford forums that Ford used something similar (variable vane) for several years on the powerstroke motors, but ditched them on the ecoboost because they failed so much.
Its been a while since I was on this forum last, and great seeing information of my work here.. The VNT system can work properly just depending on how much effort it cost making it work. Of course the number of customers just aren't there for some thing cost over $2500 to and couple of days to build, How ever the technology is and I'm more then happy spending spare time on this idea exploring its potential. Below is my latest work the SS-4 Alpha duel ceramic roller bearing turbocharger. It is made to match a 3582R's power while making close to 3076's response as possible. On a Rb25det with factory cams, usual mods, high mounted and externally gated. I'm pulling 435rwkws . Turbocharger build 25psi by 4244 RPMs while making 200rwkws by 4000RPMs. Compare to 3582R equivalent in .82 turbine based on the same car: more power and more torque through out the rev range with 431rpms better in response. That is a huge difference when comes to improving response and drive ability of turbochargers in this HP range. [yt]f1L90xFrUyw[/yt] Good thing about it is the disappearance of the torque dip before the 3500RPMS range. The car has solid linear acceleration without any flat spots or sudden acceleration from turbo lag.
It's RPM NOT RPMs Revs per minute NOT revs per minutes There is no sense in telling us you have measured x amount of revolutions then not giving us the time frame that measurement occurred over - by saying minutes you've said it's more than one. Sorry it's just a pet hate & makes people look retarded when they Americanize & screw up a pretty simple abbreviation.
When you go shopping Glenn I hope nobody's ever asked you to put in you to type in your bank card PIN number.
