Octane Ratings, when did they drop

Synchros shot? Weird noises while shifting? Not sure what needs to be replaced?
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watkins
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Re: Octane Ratings, when did they drop

Post by watkins » Mon Oct 15, 2018 9:04 pm

From my perspective, thats far too large of an engine for a four cylinder. The rotating assembly becomes so big and heavy that it cancels out the theoretical fuel savings from not having as many cylinders.
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Re: Octane Ratings, when did they drop

Post by Rope-Pusher » Mon Oct 15, 2018 9:37 pm

Usta was that valves per liter was kind of a measure of how much power one, or two, might get from a given engine design. High-end sports cars often had many small cylinders in order to increase the power output for a given displacement limit.

There are more ways to detach the epidermis from that feline now, thanks to improved manufacturing, improved engineering technologies, and a lot of cubic money being tossed around.

Thanks to valve spring metalurgy, even 16 valve Nascar motors can spin fast enough to make some serious power and last for 500 miles of racing.

Multivalve motors have become mainstream, as have turbochargers, multiple-fuel injector location schemes, electronic control of boost and knock control and real-time valve lift and duration control.

Multi-sparkplug Hemi engines can make horsepower cheaply when naturally aspirated, or grandly when supercharged, and all that with only 2 valves per cylinder.
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Re: Octane Ratings, when did they drop

Post by watkins » Tue Oct 16, 2018 12:52 am

Rope-Pusher wrote:
Mon Oct 15, 2018 9:37 pm
Multi-sparkplug Hemi engines can make horsepower cheaply when naturally aspirated, or grandly when supercharged, and all that with only 2 valves per cylinder.
If and when the Hemi goes the way of the dodo, theres no way the replacement will be nearly as simple, reliable, and relatively efficient. Im not looking forward to that day.
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Re: Octane Ratings, when did they drop

Post by Rope-Pusher » Tue Oct 16, 2018 8:33 pm

watkins wrote:
Tue Oct 16, 2018 12:52 am
Rope-Pusher wrote:
Mon Oct 15, 2018 9:37 pm
Multi-sparkplug Hemi engines can make horsepower cheaply when naturally aspirated, or grandly when supercharged, and all that with only 2 valves per cylinder.
If and when the Hemi goes the way of the dodo, theres no way the replacement will be nearly as simple, reliable, and relatively efficient. Im not looking forward to that day.
The saving grace for DIYers will be that so many of them were installed during the last 15 years in Ram pick-m-ups, Durangoes, Grand Cherokees, Chargers, 300s, Magnums, Challengers, Aspens, and Commanders that they will be available for years at an "Experienced Car Parts Center" near you.
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Re: Octane Ratings, when did they drop

Post by watkins » Thu Oct 18, 2018 10:57 am

But that wont have any impact on new production vehicles. The stuff I actually deal with daily.
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Re: Octane Ratings, when did they drop

Post by theholycow » Thu Nov 01, 2018 4:10 pm

Rope-Pusher wrote:
Wed Oct 10, 2018 8:23 pm
I remember......what was it I remembered?....oh yeah.....I remember when they called it Ethyl and not lead. People knew lead could be poisonous, but Ethyl, why she was some girl your dad dated before he met Mom, right? You too could get lucky with Ethyl like dear old Dad prolly did.
My dad still thinks it's hilarious to say "I have to go pump Ethyl". :lol:
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Re: Octane Ratings, when did they drop

Post by Rope-Pusher » Thu Nov 01, 2018 10:21 pm

theholycow wrote:
Thu Nov 01, 2018 4:10 pm
Rope-Pusher wrote:
Wed Oct 10, 2018 8:23 pm
I remember......what was it I remembered?....oh yeah.....I remember when they called it Ethyl and not lead. People knew lead could be poisonous, but Ethyl, why she was some girl your dad dated before he met Mom, right? You too could get lucky with Ethyl like dear old Dad prolly did.
My dad still thinks it's hilarious to say "I have to go pump Ethyl". :lol:
Whale, yanno that Ethyl's nuttin' but a hussy, right?
[youtube]https://www.youtube.com/watch?v=XtzoUu7w-YM[/youtube]
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