Forum Home
PC World Chat
Thread ID: 70673	2006-07-12 06:04:00	OT - Does US have different octane rating compared to us?	SKT174 (1319)	PC World Chat

Post ID	Timestamp	Content	User
470295	2006-07-14 06:37:00	But I ride a bicycle, Joe, and the only emission control is that I don't eat lots of beans. We don't have many "444" (cubic inch?) motors. And a good thing, too. I don't think we have many sodium-containing valves. As a kid, I often hoped to find some so I could experiment (play) with sodium. :( In the US someone might sometimes drive coast to coast, about 4000 miles. In NZ, people might drive from Wellington to Auckland, or from Christchurch to Invercargill; either is about 400 miles. And our "open road" speed limit 100 km/h ... about 60 mph.	Graham L (2)
470296	2006-07-14 09:29:00	Sodium filled valves were standard on Fords, Chevys (All of GM actually), including Cadillacs, Lincolns, Buicks, Oldsmobiles, however Chrysler abstained for a while, offering sodium in their 440's and HP 383's. Many engines still use them here in the US. as already said they are not comman here. the only place i've heard of sodium valves are sports cars. the sodium helps keep the valve head cool. when i was into race cars/hod rods etc it was common to use once peice stainless valves as the where more durable than the soudium ones. Cats typically last 200,000 miles although engines that burn oil or if they can even find leaded fuel (Mexico maybe) will find them contaminated and the core melted into a puddle. most people here don't buy there cars untill they have done over 100,000 kms and concidering the amount of wound back cars a lot have done near on 200,000 (ie jap imports) hence why they are ripped out and thrown away. EGR reduces the stoichemetric tendencies of engines running lean (17:1 AFR's) and the possibility of fusing nitrogen to oxygen molecules making nitrous oxide...the eye burning nitric acid forming emission. nice techno babble ;) putting that into english, EGR which is basicly inert gases snufs out the flame a bit so the peak temp dosn't get high enough to cause nitogen and oxygen to combine makeing NOX, ie polution. EGR's only operate at cruise if engine temp is normal (above 185 F) and power demand is just to maintain speed without hills or strong headwinds. and any off throttle where no power is required eg going down a hill with no foot on the gas. its a good time to lessen the amount of polution. EGR's lower fuel octane requirements, reducing knock and ping and improve fuel mileage.low octane requirements...yes, but don't forget EGR is often used when the motor dosn't actually NEED high octane anyway which kinda rules that out. however because EGR costs performance (due to lower heat and less thermal exspansoin) timing is often advanced to regain some lost power when the EGR is turned on. (one thing you have to watch if you disable the EGR). EGR's are installed on all US multi-fuel military vehicles that don't run diesel as an economy device to improve fuel mileage. o com'on please! compare apples with space ships for goddness sake ! military vechiles have nothing in common with normal cars. There were a lot of shadetree mechanics here that also resisted the EGR's, Cats, lead-free fuels, fuel injection, oxygen sensors, feedback carburetors and NOx devices. They put ball bearings in hoses to block signals to them; they re-routed vacuum lines to suit their old fashioned ideas, they removed 195 F thermostats because everybody "knows" and engine cannot run that hot and live. They by-passed every emission device they thought was bad ju-ju because they didn't understand what was going on. They poked holes in monolythic catalytic barriers, and poured out the pellets on the bed type because they were ignorant. the reason they did all that, and why they are STILL doing that is because emmision systems rob power from a motor. 2ndly those systems in high milage vechiles CAUSE more problems and emmisions than they are worth. one reason we block EGR in diesels is because they soot up the intakes so badly the motors run rich causeing head problems and not to mention more polution. My Amigo right now has 264,899 miles (429,531.24 Kilometers) on the original clutch, water pump and engine. I am keeping it forever.i won't mention how many times we put the old falcon around the clock then. every one has stories of cars that live forever. It's not uncommon for me to drive about 20,000 miles a year in my Blazer, another 30,000 in my Amigo, and my wife gets another 40,000+ in her van. (That's about 144,840.60+ kilometers per year if my calculator is correct). The US just drives long distances...that's all. I used to drive 160 miles (260 Kilometers) to work daily. Others drive longer than that. thats actually fairly similar to over here dispite our small country. mind you i wonder if you would do that if you had my kind of terrian! (flat..straight.....where?). sorry to knock ya joe but we have for many years ripped out emmision controls and have gained power as well as fuel encomy. we have also run high octane fuel in low compression motors for many years without anyone complaining that it stuffed a motor.	tweak'e (69)
470297	2006-07-14 10:08:00	It has to be remembered though, where Joe is coming from. California progressively introduced the toughest emission control laws of anywhere from back in the early 1970s onwards. Long before most other countries, they also started going lead free back then, when UK and Europe, like NZ have only recently gone lead free. That was why they had to start producing improved hardened valve seats, and sodium filled valves so early on. As an aside the RR Merlin engine had sodium filled valves. That's why they had to have all those emission control devices, but they have never been particularly concerned about fuel economy until more recent oil shock times, neither have they paid exhorbitant government taxes on fuel, unlike the Europeans. In fact until that time, their engine design, on the whole, was not that flash, even backward, as compared with the smaller higher performance OHC European cars, goodness gracious, they were still persisting with side valve engines until 1965 (American Rambler), and their motorbikes engines were similarly backward, and pathetic even by the standards of 1950s/60s British bikes I just cannot understand the business of high octane causing engine melt-down, and this is where I take issue with Joe. If that were the case, it would be a well known phenomenon world wide, common knowledge etc, and there would be warning notices in user manuals and on filling station fuel pumps, and on filler caps etc. My Mazda E series owners manual says "Your Mazda will perform best with regular unleaded fuel having a research octane number of at least 91." Then it goes on to warn about using a lower rating could cause knocking and engine damage, nothing about the engine melting if higher octane is used.	Terry Porritt (14)
470298	2006-07-14 10:21:00	yeah true . back in those old days they didn't really have the technology to do the standards they set . mind you back in those days privateer race car outfits used to regualry beat the factory teams . shows how much the factory guys knew . i know the jap motors have been known to made to run hot for emmision purposes, mayby the yanks did the same trick exspect a bit higher hence the need for sodium valves . "Your Mazda will perform best with regular unleaded fuel having a research octane number of at least 91 . " ditto with new toyota i was looking at today .	tweak'e (69)
1 2 3