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    Buick 215 Trans bolt pattern

    I assume you're aware that the Brabham-Repco v8 that won an F1 world championship was based on the Oldsmobile 215? Cousin to but not the same as the Buick version.
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    Buick 215 Trans bolt pattern

    I don't know about the US, but they've been hitting up the Rover version in the UK for decades. There's a plethora of stronger rods, pistons, cranks etc. available in the UK. They fitted the 3.5 litre v8 into everything.
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    reduction drive specs

    I really wish I had / have access to one of those Rotecs! It would keep me entertained for ages. Some of the issues I'm talking about are related to sensors in a production environment, where characterising each wheel etc is less practical. Since we've measured (and simulated) the system, we...
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    reduction drive specs

    Re the soft coupling I referred to earlier : I went through my old emails. For a 6 cyl 4.2 litre diesel, the coupling cost 6,000 euro in 2011. The company was Tectos. I haven't looked at their site for 10 years, but it used to have a lot of useful information on TV damper selection.
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    reduction drive specs

    Part of the problem with measuring a rotating element is that any noise on the signal (eg from vibration) will appear as a spurious shaft acceleration / deceleration, maybe an order of magnitude greater than the signal you're trying to measure. In my job, one of the sensors we use is a VR or...
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    reduction drive specs

    I bought an engineered TV (soft) damper for a dyno about 10 years ago. It cost multiple thousands of (AU) dollars, and I had to provide them with: Engine inertia Load inertia Engine peak torque # cylinders Firing order Rev range (min/max) It did the job beautifully, but was specific to that...
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    reduction drive specs

    I know I am repeating myself, but here goes: A company I worked for developed a new compact engine dyno. It was extensively tested with a number of v8's in the 300 - 500 HP range. They sold a number to performance shops, who were happy with them (running v8's). Then some were sold to people...
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    reduction drive specs

    It's interesting to see slow-motion footage of a toothed cambelt drive. At certain revs, there's a significant "standing wave" oscillation of the drive side of the belt. On the auto engine I know best (Toyota 4AGE), they fitted a hydraulically damped belt tensioner on the final high-power...
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    Lighweight opposite 2-stroke engines

    That's because cloud 9 is (water) vapour.
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    reduction drive specs

    It would be possible to have a "soft" belt drive system by using a (mildly complex) sprung "tensioner" on the drive side of the belt. The dynamics gets interesting, as the effective spring rate changes as the belt gets straighter. There's also the fact that the tensioner, as a spring/mass...
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    reduction drive specs

    We had loads of trouble years ago with an engine dyno design for a 3 cylinder diesel. It ate drive components that were fine for a v8 of nearly 10x the power. A soft coupling (rubber based) sorted most of the TV issues, but disintegrated doing long runs - basically, the damper is converting a...
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    Auto Engines Aren't Designed to Take Full Power for More Than a Few Minutes...

    Come to think of it, could the hot / cold test have some similarly to a glider tug or skydiver type mission? Full power at full load for x minutes then descend.
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    Auto Engines Aren't Designed to Take Full Power for More Than a Few Minutes...

    I've worked with an OEM on durability testing. That's why I have a good opinion of auto engine durability (within limits). The reason I state "within limits" is that bastard issue - resonance. Any change to what was bolted to the engine required re-testing, among other things to ensure that...
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    Auto Engines Aren't Designed to Take Full Power for More Than a Few Minutes...

    What would be a reasonable over speed margin? eg Direct drive auto v6 / v8, propped for say 3,200 RPM at cruise. That's way below both max power and redline, so add 15% to the 3200 (say 3700 rpm)? PSRU, 4 cyl propped for say 5,000 rpm - is that a resonable estimate? (I'm basing it on an ej20...
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    Auto Engines Aren't Designed to Take Full Power for More Than a Few Minutes...

    I accept the comments re aircraft engines, but the question remains : for an auto conversion , what is the appropriate test RPM? I'd say max HP, or maybe max torque, as redline is not an appropriate measure.
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    Auto Engines Aren't Designed to Take Full Power for More Than a Few Minutes...

    While I agree with this post in general, I have one quibble: Max HP is almost never at redline RPM, so an engine propped for max power won't reach redline as the power curve drops past peak. ps Having been in the dyno industry for over 30 years, I heartily agree with you on the older quoted...
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    Honda K20C1 FK8 Auto-Engine Conversion

    "We chopped up the guibo to reduce cabin vibration" is more than a bit worrying, and smacks of a band-aid solution. An actual engineer might have started with "why do we have this cabin vibration?".
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    Crashes in the News - Thread

    I'm imagining a line of planes hanging nose-down like bats. How much of a vertical drop would you need to get to flying airspeed and horizontal before you hit the ground? Give me a target speed and I'll work out the drop required, but I don't know how much more room you need to get it...
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    Honda K20C1 FK8 Auto-Engine Conversion

    That ALL CAPS style of writing is both distracting and hard to read, and comes across as rude. I don't see the point - caps are for EMPHASIS, and using them for the whole post makes that meaningless. As far as the content goes, I don't have a dog in that fight, so I'll leave it to others.
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    Wiring in a backup battery

    I've had a memorable rally stage where the alternator failed high - as the navigator I was switching loads (lights, fan, demistor etc) to keep the voltage under some sort of control - I think we never got over about 20v, but that's with over 600 watts of lights to load the alternator with. And...
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