The Triflux Engine - Italian Mechanical Genius At Its Finest

Video Description

A turbo academy in one video: https://youtu.be/MTdIB4-PmyA?si=ov8ivmGipvH2mPS5 Support the channel by shopping through this link: https://amzn.to/3FLpqzm Patreon: https://www.patreon.com/d4a Become a member: https://www.youtube.com/channel/UCwosUnVH6AINmxtqkNJ3Fbg/join Today we are going back in time! Back to a time when the Italians were on top of their game and knew what they were doing. Yes, we are going back to the 80s, more specifically to Lancia of the 80s, and we are going to talk about this genius engine, the Lancia Triflux engine. So why is this engine genius? Because it managed to create an engine with a low boost threshold and minimal turbo lag in an age when turbo technology was still pretty primitive. You see, back in the 80s, turbos were spreading rapidly through motorsports because manufacturers, constructors and racing teams realized that, yes, there is a replacement for displacement and it’s called a turbo. You put a big turbo on a four-cylinder engine and suddenly you’re making the power of an engine that has twice the displacement and number of cylinders. A big turbo has a big compressor wheel and big compressor wheel can push massive quantities of air into the engine. If you have massive quantities of air you can add massive quantities of fuel which results in massive combustion events and massive torque and power. But to spin up a big compressor wheel, you also need a matching big turbine wheel and a matching big turbine housing. And that’s great too because a big turbine wheel and housing means there’s lots of space for exhaust gas to pass by, which means that a big turbo doesn’t choke the engine which further contributes to good breathing and impressive peak power numbers. You see to create boost, i.e. a pressure increase in the intake manifold the compressor wheel must spin at a certain speed and because the compressor wheel is fixed to the turbine wheel that means that the turbine wheel must spin at a certain speed and to bring a big turbine wheel to our desired speed we need a large amount of exhaust gas. An engine is simply unable to generate sufficient flow of exhaust gas for a big turbine wheel at low rpm. The result is a high boost threshold. Your boost threshold is the rpm where your engine starts producing significant boost and with a big turbo back in the 80s, it wasn’t uncommon to have your boost threshold at 4000 or even 5000 rp,m creating an engine whose power and torque curves had the smoothness of a rectangle. Usually, they were lethargic below the boost threshold and completely insane above it Lancia was one of the first manufacturers to actively try and combat both a high boost threshold and large turbo lag. Their first attempt was the revolutionary and legendary Group B Lancia Delta S4 which was the frist car ever to use twincharging, where both a supercharger and a turbocharger where employed on the same engine. The supercharger essentially filled the low rpm gap left behind by the big turbo. Being driven directly by the crankshaft using a belt, a supercharger does not need to wait for exhaust gas flow to accumulate to a sufficient quantity. The result is lagless torque delivery even at the lowest of rpm. But again, let’s not forget the all-important rule…no free lunches. The supercharger pays for its instant responsiveness with power-sapping parasitic losses and increased heat. So for the successor of the Delta S4, the ECV, which stood for Experimental Composite Vehicle, Lancia decided to ask a very difficult question… "How to have the power potential of a big turbo but the responsiveness and boost threshold of a small turbo, all without the heat and parasitic loss of a supercharger". If you look at the combustion chamber of pretty much any engine ever made with four valves per cylinder, you can be sure that 2 valves will be intake and 2 valves will be exhaust, and they will be in pairs. In other words, the two intake valves will occupy one half of the chamber and the exhaust valves the other half. The result is of course that we have the intake manifold of the engine on one side and the exhaust manifold on the other. Well, the designer of the Triflux…Claudio Lonbardi thought this was boring. So he decided to mix things up and do a bit of a wife swap arrangement. Now each half of the combustion chamber contained one intake and one exhaust valve. Basically, one intake and one exhaust valve trade places. Seems like a very small change, doesn't it? Well, it changes everything. A special thank you to my patrons: Daniel Zwoa Meda Beda valqk Toma Marini Cole Philips Allan Mackay RePeteAndMe Sam Lutfi Cakeskull #d4a #lancia #rally