The Car Shopping Round (Round 64): Tears in Heaven

Well. Nice undercover car maybe?

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Well now it seems we have an excellent range of offerings along a broad spectrum of all variables, given everybody has chosen to approach this from the point of either accentuating one feature (vans for utility and practicality), to another (all those bigger engines producing heaps of horsepower), to trying to make something maximally balanced (the hardest path imho). This implies a wonderfully balanced set of rules.

Have fun choosing Bob :stuck_out_tongue:

P.s. sad that I no longer have the crown of most economical, at 30.4mpg. but that being said at least my car can sprint :joy:

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Meh. I always chuckle when people talk about fuel economy and police vehicles. The things are either driven at WOT or sit idling for 75+% of their shift (or the whole day if it’s a shared car). I did try to make my car a little economical, but the reality of it is that these things get nowhere near advertized milage.

For example, we have a 2014 or '15 Dodge Ram 1500 police truck that consistently manages 5.3 MPG. It rides around at low speeds or idles all day. I think our 2015 Caprice gets around 8 or 9 MPG under the same conditions.

For the purposes of CSR27, economy matters. But in all reality, it just doesn’t make a difference unless the cars have an opportunity to cruise for extended periods.

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I’m aware that the economy figure is derived from am attempt to simulate normal driving practices for mixed application, which is really not what police work involves the vast majority of the time. My rationale for placing value on this (apart from looking numbers) is as a hopefully acceptable surrogate of overall fuel consumption regardless. In particular I insisted on early spool single turbo because achieving maximal torque with forced induction at lowest possible rpm will hopefully yield maximal efficiency for low speed applications (simplistically speaking).

I Wonder if my ruminations on this sufficiently spooked @phale and therefore whether I can claim any degree of credit for his last minute decision to change from the much more powerful v6 :wink:

You caught me :smile: Although lore was also part of my decision, Adenine doesn’t make V6s after they spent millions developing VVL technology for their inline engines! (Although I really liked the idea of a muscle SUV haha)

If police cars are idling all the time, then that just makes low-RPM efficiency all the more important.

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That’s where engine start-stop technology comes in. But AFAIK that wasn’t around in 2000. :stuck_out_tongue: I already made a thread asking about extra fuel economy technologies.

but start stop just stops the engine a couple of minutes though. anything longer would wreck havoc on your battery life and MAYBE electrical system.

i think cylinder deactivation system would be much more useful.

2 out of 6 in a 6 cyl car would suffice to idle and power some auxilaries me thinks

Hopefully I can start having the first round of reviews ready by mid Sunday.

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Start/stop would also cause excess wear on the starter motor and the engine. The majority of engine wear comes from startup as oil is only starting to flow.

well why not make the oil pump be able to run with an electric motors then?

we have a coupling for radiator fan that only turns on when needed. why not make the same thing for oil pump? we’re already using dry sump anyway.

also when people claim ‘excess’, i actually never heard of anyone actually pointing to a study on it.
more wear? i totally believe it.
but would that extra wear actually be damaging?
how much damage does it actually do?
what is the threshold before that extra wear will damage the engine?
how will it actually realistically impact the engine over it’s lifetime?

i want to believe it, but i just can’t find the proof of it.

well in Drag racing multiple start stops can cause damage between rounds if you have not first prepped oil pressure, fuel pressure. However this is only in the big boy league’s where engine tolerances are tiny, huge compression ratios are used massive boost levels and the chance of failure of bearings, piston rings etc is HUGE (even when run in) not to mention on average a nitro car will make between 2500-8000hp depending on tune and weather and the most damage occurs on engine shut off (after a full 1/4 run) but there is always the risk of starting an engine cold with no oil pressure and blowing the engine before it even warms up. Again this is talking BIG number cars and $100000+ engines.[quote=“koolkei, post:4690, topic:6447”]
well why not make the oil pump be able to run with an electric motors then
[/quote]

This isn’t too far from reality using a dry sump or a wet sump with a dry sump pump

I see no reason why the sump drive belt could not be powered by a electric scavenger pump (similar to what rear mount turbos use) or a separate electric motor as below (yes I realize that is a water pump…and a holden :rage:)

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warning terriple pun ahead
[spoiler]
HOLDEN a minute. that’s not a water pump
[/spoiler]

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What should matter more than just one number that defines efficiency is this

good, low emissions and fuel consumption in the power range most used

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I think I made either the right compromises or completely the wrong ones.

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I think the main reason no one uses an electric oil pump to reduce wear is because then you wouldn’t have to take it in for service as often.

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umm… as i said. can’t you use a coupling? it’s only powered by an electric motors when the engine is turned off.

so it wouldn’t really add too much problem
even if the electric motor has problems, the whole start stop system can just be disabled temporarily until it’s fixed. nothing critical.

sorry mate :smiley:

For what?

Presumably cutting off the N of your brother in the quoted list haha. Though then really the one who needs the apology the most would be vri404, since lordvader totally 404d her :joy:

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hahahah get 404’d m8