Roinik

Leave it outside during a Canberra storm and you'll have that fresh golf-ball aero profile in no time.

Seriously, get more air to the back. Diffuse it from underneath, bring it in from the sides, whatever.

I have been trying to figure out if I can justify calling it a Kamm back or not... leaning towards “not”, mostly due to the rounded edges on the back corner.

The Lancer coupe looks like a better shape to my untrained eye - tapered turret, longer boot with square edges.

But I really don’t know, and couldn’t find a viable coupe to start with - seems like Mirages were sold new to mums and P-platers in about equal numbers, but the coupes went exclusively to P-platers and were variously flogged to death, attacked by ricer mods and/or badly neglected.

@Ex850R, there’s a definite chance of some wool-tuft testing.

    The vehicle mass directly related to engine load. More load more fuel. You should also lower, and stiffen the drive train and suspension. Loss of inertia

    • Spac replied to this.

      Going by aircraft dynamics and engine performance,they fly higher in thinner air and use less fuel and can go faster so you should get a lift kit really..............

      egg

      The vehicle mass directly related to engine load. More load more fuel. You should also lower, and stiffen the drive train and suspension. Loss of inertia

      The load is only particularly relevant when accelerating the mass.

      There’s plenty of talk about this on ecomodders.

      The lowering is a given. It reduces the frontal cross sectional area of the car by the amount that the tyres are “hidden”, and (more importantly) it reduces the air that can get under the car.

        @Spac

        Mythbusters proved that turning it into a golf ball will significantly improve the areo

        An engine is continually under load. Just varying amounts. I'd also look at thin, hard tyres. If your purely concerned with your fuel consumption the use 98 with octane booster.

        And unfortunately due to earths gravity your always accelerating

        https://www.wired.com/2012/08/fuel-economy-vs-mass/

        • Spac replied to this.
          egg

          https://www.wired.com/2012/08/fuel-economy-vs-mass/

          Yeah, so reducing the mass of the Mirage won’t change its engine or its aerodynamics.

          I will absolutely experiment with fuels, but past experience strongly suggests that 98 octane fuel won’t improve the fuel economy of a SOHC 4G15.

          It is a common myth that more octane magically makes more power and/or improves economy. Octane ratings are ONLY about detonation resistance - if it doesn’t want to detonate on 91, then giving it more octane does nothing for you.

          The whole topic is confused by ECUs being programmed to use knock sensing to alter fuel and ignition timing, but the fundamental point remains: more octane only helps if the motor can use it. As I said, I will definitely experiment, but I seriously doubt that a 1990s Mitsubishi commuter car will benefit from more than 91 octane dishwater.

          This statement regularly outrages people on various forums and FB pages, but has never been refuted:

          Use the lowest octane fuel that reliably avoids detonation.

            Egg, mass is only a fraction of the story when you're moving. It is important if you have a lot of hills to climb though. So, mass relating to friction/rolling resistance is linear. Mass related to hill climbing is linear, however the energy related to the rate of ascent is squared.

            Aerodynamic loss related to the front of the car (aka wind resistance) is related to the (area x velocity)cubed.

            The long and short of it is to lower aero drag wherever you can, maintaining the radiator cooling inlet at the static point, venting that air behind the car to minimise the disturbed low pressure created by the sharp trailing bluff tail (aka aero drag) and to drag as much air in behind the car to lower the drag further. That is why the most aero shape is a tear-drop.

            @Spac check out the Milan SL velomobile for some ideas.

            6 days later

            I'll be following this to see what improvements to economy your hypermiling mods will make.

            And I might even apply some to my daily driver (I too daily an econobox)

            a month later

            Progress was dragging this home yesterday. It is obviously rooted, but has 55,000km on it so was a cheap way to get a good motor and a set of extractors.

            Breaking the caliper off the upright and making the brake rotor disappear is interesting.

            time for 11:1+ compression and atkins cycle via updated cams?

            • Spac replied to this.

              also shorten the stroke for less displacement

              Philia_Bear

              time for 11:1+ compression and atkins cycle via updated cams?

              Funnily enough, we were talking about that today.

              Is Atkins Cycle just Miller Cycle without the forced induction? Or is there a subtlety that I have missed?

              It is very clear that the vast majority of motoring journos have no idea how either of them work.

                  Can you make it look like this?

                  Aptera Solar-Powered Car With ‘1,000-Mile’ Range Gets 7,000 Preorders for Delivery in 2021 (goodnewsnetwork.org)

                  @Spac

                  This should be your solution :-)

                  https://www.youtube.com/watch?v=EEcrNviqaNg

                  Spac

                  https://ozvolvo.org/discussion/comment/188472#Comment_188472

                  Funnily enough, we were talking about that today.

                  Is Atkins Cycle just Miller Cycle without the forced induction? Or is there a subtlety that I have missed?

                  It is very clear that the vast majority of motoring journos have no idea how either of them work.

                  Yeah, Atkinson is just miller without the forced induction

                  https://en.wikipedia.org/wiki/Atkinson_cycle

                  You would need intake cams with longer duration of open period

                  if you also have VVT you can switch between otto and atkinson at will depending on load

                    Mike is on the money, the late close on the inlet reduces the effective compression ratio on the compression stroke while maintaining the higher CR for the expansion stroke.

                    18 days later

                    If you are looking long term to stop using fuel-petrol for a car, and want to invest long term, buy a good quality solar panel set-up. Then buy a nissan Leaf. I know a guy and for $4 of electricity, he gets 250ks. But the power is from coal fired. So buying a good solar panel set-up would make the electricty for the Leaf a lot greener". Plus they they have heaps of grunt, and are fun to drive.

                    • Spac replied to this.
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