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Thread: Why no push rod engine?

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    Why no push rod engine?

    I was wondering,
    Push rod engines now can be made with same mpg or better, and the same life expectancy as dohc engines.
    They have higher torque and HP numbers, if I'm correct.
    And actually do well with a turbo.

    Why not combine the extra torque and HP, to aid the small 3 cylinder?
    Reliability is not really much of an issue with direct or port injection.



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    Senior Member MacClyver's Avatar
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    Quote Originally Posted by ProDigit
    Reliability is not really much of an issue with direct
    Direct injection what? 20000 psi fuel pressures, tiny heated nozzles and potential chaos if some silt were to be acquired from subpar gas... Mirages with port injection FTW!

    That said my car zero(you know first but never owned it) was a 98 Malibu 3.1 V6 OHV. It had torque for sure but never thought anything of it. I thought that was just part of having more displacement and cylinders.

    Summer car in use

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    I'm not sure if push rods work with multi valve setups that newer cars have.
    -Karl B. 2019 Mirage SE CVT and 2015 Mirage DE 5 speed. Plenty of other cars as well.

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    Port is cheaper, but direct is better.
    And direct injection is safe. It's used on a lot of engines. Doesn't matter if it's dohc or pushrod.

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    Times have changed for the better!
    Pushrods and side-mounted camshafts were standard from the 30's to the mid 60's, just as three main bearings instead of five in a four cylinder engine. Engines had their cylinders directly cut into the cast iron block, piston rings were also of cast iron, and pistons had overlong skirts.

    Today we have engines with 4 valves per cylinder and situation-dependantly adjusted valve opening, cylinders are of steel and piston rings too.
    I don't miss the archaic stuff one bit!

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    GM still has a pushrod V8. I'm sure they are direct injection now. Ford came out with a 7.3L pushrod V8. I can't think of a modern pushrod multi cam engine?
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    Quote Originally Posted by Fummins View Post
    GM still has a pushrod V8. I'm sure they are direct injection now. Ford came out with a 7.3L pushrod V8. I can't think of a modern pushrod multi cam engine?
    Chevrolet Corvette. But for an economy car like the mirage, high rpm doesn't matter much.
    Just give it wider gear spacing. Make it a 1 liter turbo diesel pushrod, and you don't need no multi valves.
    Have it develop all it's torque at 2k rpm, and HP with turbo at 4k RPM, With a redline of 5k rpm, is more than enough.

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    Quote Originally Posted by ProDigit View Post
    Chevrolet Corvette. But for an economy car like the mirage, high rpm doesn't matter much.
    Just give it wider gear spacing. Make it a 1 liter turbo diesel pushrod, and you don't need no multi valves.
    Have it develop all it's torque at 2k rpm, and HP with turbo at 4k RPM, With a redline of 5k rpm, is more than enough.
    We had that decades ago, today it just doesn't cut the cake.
    Daihatsu made a diesel version of their very modern overhead cams gasoline 3cylinder 1.0L engine in the late 70's. It was very economical, but never in your life would it meet today's emission standards, no matter what country.

    Hey, its 2020, crude pushrod and side-cam engines turned customers away before 1960. Who with a straight mind would buy such trash today?
    What about pre-war flat-head engines with side-valves or even sleeve valves, copper DIY head gaskets, lead main bearings, leather clutch or clutch bands like a tin Lizzy, and all the rest made of cast iron? Museums are full of antiques, but I don't want to have to rely on those.
    I prefer a modern engine, made of high-pressure die-cast aluminium, overhead cams with variable cam control, four valves per cylinder, a modern ECU with at least 256 stored running conditions, and all the other stuff to make it pass emission tests and make it exceedingly economical, reliable, and last 3 times longer than a typical 1970 engine.
    Last edited by foama; 06-15-2020 at 03:06 PM.

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    Quote Originally Posted by foama View Post
    We had that decades ago, today it just doesn't cut the cake.
    Daihatsu made a diesel version of their very modern overhead cams gasoline 3cylinder 1.0L engine in the late 70's. It was very economical, but never in your life would it meet today's emission standards, no matter what country.

    Hey, its 2020, crude pushrod and side-cam engines turned customers away before 1960. Who with a straight mind would buy such trash today?
    What about pre-war flat-head engines with side-valves or even sleeve valves, copper DIY head gaskets, lead main bearings, leather clutch or clutch bands like a tin Lizzy, and all the rest made of cast iron? Museums are full of antiques, but I don't want to have to rely on those.
    I prefer a modern engine, made of high-pressure die-cast aluminium, overhead cams with variable cam control, four valves per cylinder, a modern ECU with at least 256 stored running conditions, and all the other stuff to make it pass emission tests and make it exceedingly economical, reliable, and last 3 times longer than a typical 1970 engine.
    Like mentioned, modern push rod engines are more energy efficient, comply with emission standards, and are reliable (200k miles).
    A lot of modernization, technological advances, better metallurgy and alloys, improvements in engine design, smaller tolerances etc... Make modern push rods reliable. Diesel engines aren't your standard 1968 smoke puffing monstrosities either anymore. Many diesel engines run cleaner than their gasoline counterparts, thanks to advances in catalytic converters.

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    Quote Originally Posted by ProDigit View Post
    Diesel engines aren't your standard 1968 smoke puffing monstrosities either anymore. Many diesel engines run cleaner than their gasoline counterparts
    Gotta love them clean diesels lol https://en.wikipedia.org/wiki/Volksw...ssions_scandal


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        click to view fuel log View my fuel log 2014 Mirage SE wussie cvt edition. 1.2 automatic: 37.4 mpg (US) ... 15.9 km/L ... 6.3 L/100 km ... 44.9 mpg (Imp)


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