Increasing the power of your iron horse is always faced with a dilemma: the larger the turbine and power, the higher the output speeds for boost and longer spool. The output was invented a long time ago - this is a twin-turbo.
The most effective, according to the scheme, implementation of the two-turbine system is Staged Compound Compressors.
The potential of this scheme is such that it is calculated that it is possible to obtain a pressurization of 1.5 bar already at 2000 RPM and 2.4 bar starting from 3000. and further to cut-off
In connection with the transition to MAP sensor, very quickly the question arose - and what to replace the stock MAP sensor, which is only 2.5 bars or 1.5 bars of supercharging. Almost a full-time solution for 9k, namely 3bar MAP sensor did not suit because of ambition to blow more than 2 BAR of boost. Having studied the market of existing automotive products, I found that there is no MAP sensor which would work from 0.2 BAR (abs) to 4 BAR. And if with 4 BARs of the upper limit everything is more or less clear, then with a lower limit of 0.2 bar, everything turned out to be not so simple. The fact is that the lower limit is the work on idle and in gas release modes, which directly affects the stable operation of the engine in these modes, as well as the fuel consumption. Plus, very tricky features of filters of ADC trionics, which are tuned to the frequency response of the stock MAP sensor. Yes, yes, having recorded a sound signal from the MAP's through the sound card, I heard such sounds there that in time to amplify and apply to the built-in acoustics
So, at the moment, already the 7th iteration of MAP sensors, thermostabilized, with correction of the frequency response, compatible with the standard of the breakdown and short-circuit diagnostics
And most importantly, that, past the upper limit of 4.1 bar, it was possible to make a lower limit of 0.1 bar, which would have a very positive effect on fuel economy and overall fuel accuracy.
Time ago I began work on the twin-turbo system on saab Despite the seeming simplicity, the embodiment in a gland on a gasoline engine, without using any factory twin-turbo system for a diesel engine, involves the problems of finding and manufacturing TT elements. In addition to welded products, the TT system consists of A large turbine, a small turbine, a flap on the hot part, a bypass valve on the cold part and a highgate. In the course of time, a lot of spare parts were bought, which could be suitable for their characteristics, their testing, testing and rejection.
With a large turbine, there was no choice - only its cost Wastgate is a proven solution from Tial A small turbine - came from younger brothers by brand The bypass valve on the cold part brought a lot of trouble, but in the end there was a product of the concern VAG. And the most difficult thing is the damper on the hot part. In order to find the optimal solution, it was necessary to go through all the circles of hell - buying valves from the Chinese, trying to draw and produce in Khrunichev space rocket plant (refused because of the difficulty, having already undertaken, feeding breakfast for six months), buying a product of the VAG concern, trying to manufacture a metal 3D printer ... ... And Finally - found a working solution from the Japanese.
And now, the whole kit is assembled, it is based on a fitting of geometric dimensions:
Preparing for TT: Carrying the battery into the trunk.
The release of space under the hood for the twin-turbo More precisely not for the turbines themselves, but for a short, cold intake and heat exchanger for a water intercooler. (As well as if there is room for a pre-heater)
The wire is 50 squares or 0GA of copper, both + and - are transfered. The estimated total voltage drop on both wires at the starting currents is less than 1 volt.
Everywhere outside the box in the cabin, on the plus wire is put on a protective poliamid stocking. In particularly responsible places, in addition to both wires is a shrinkage with glue Under the hood on both wires is clad corrugated and wrapped with electrical tape Plus is connected up to the starter, minus to the bolt on the gearbox, where the mass wire comes in Protective sleeves through the motor shield are made of a hydraulic hose for 2700 bar - will not be overdriven Under the hood has not yet modified the standard wiring and the battery terminals are not removed In the trunk is not yet made a fastener for the battery. The cost of the wire was ~ $120 , it took with a huge margin. Connectors, stocking, corrugation, heat shrinkage ~ $50.
9.5 hours without interruption. 1. The battery is connected in time, with disgusting terminals, is not fixed at all, not insulated, and so on. There will be another battery, LiFePO4 and it will connect via a white connector - visible on the photo next to the battery. Fuse and charge control - electronic. 2. The two wires are transfered to not violate the correct power distribution scheme with a single point + and a single point - 3. To filter out noise and jumps in the event of a sudden change in consumption, a supercapacitor for 20 farads is ordered and already shipped (for reference: in 84 farads you can start a car without a battery at all)
Usually projects of such complexity become long-term construction. A cheerfully initiated project is stuck in some technical problem and until it is solved - the car is in the garage, half-disassembled. I do this project on the principle: All technical problems must be solved in advance, the system must be made in hard, and then installed in the machine for 1 time.
Because this project had a residual priority regarding the purchase of housing and basic work - it lasts long enough. But! Nothing in the garage is not worth it, all technical and engineering problems are solved without machine downtime
The house is already there, the renovation is done - you can activate on a pleasant There was a final difficult stage - the layout and welding of the collector under the twin-turbo. To do this, I made a 3D scanner, scanned the engine, turbines and other auxiliary things. and now, in your favorite CAD select the best location of the units in the engine compartment As soon as the collector converges - it will be immediately ordered to weld it according to the ready drawings.