зацените
к вопросу про октановое число в 3л движки на МС.
Q- I've been filling up my Montero Sport with Premium Unleaded (91) gasoline but was told that all I need is 87, is this true. Are there any advantages to using 91 in my Montero Sport?
A- That is absolutely TRUE- you are basically throwing your money away by using 91 octane in either of the V6 engines (6G72 3.0L or 6G74 3.5) in the Montero Sport. High performance engines with high compression ratio's and/or aggressing timing/fuel mapping curves are at risk of preignition or detonation (ping) and especially at high RPM or a heavy loads. Higher performance engines can have octane requirements exceeding the antiknock quality provided by regular grade gasoline, which is why the manufacturer recommends higher octane gasoline. Using low octane gasoline deprives the engine of performance, and may lead to engine damage. Higher octane fuel is required in these situations to counter this problem. Higher octane will turn an " explosion" in the combustion chamber, into a "controlled burn" to keep the engine running at maximum efficiency and keep the engine running cleaner.
Both engines in the Montero Sport are relatively mildly tuned engines that DO NOT REQUIRE higher octane gasoline. Using 91 in this situation will result in reduced power output and may even result in drivability problems. Over time and mileage, the internals of your engine may start to develope carbon deposits that, if left unchecked- may actually result in a slight rise in compression. This increase of compression may result in a slight ping under heavy loads while at the same time, increasing NOx emissions (which is harmful to the ozone). This is why some of you may feel that you're engine actually runs better with premium fuel. If this is the case, you are better off having a "top end" decarb service performed on your engine rather that giving into the constant use of Premium Fuel (which will be more expensive in the long run). STP Fuel Treatment or the like will NOT remove heavy carbon deposits as you might expect. The only way to eliminate the carbon deposits in your combustion chamber is to have it phsically removed ($$) or to have a chemical decarb treatment introduced into the intake and combustion chamber while the engine is running- this decarb service can be performed an any reputable service station (just make sure they don't add a bottle of cleaner to your fuel tank and consider the service done as some stations might do). Once your engine is rid of this carbon layer- you can now go back to using 87 octane and if you prefer add a bottle of fuel treatment (for maintenance) Many reputable service stations add detergents in their fuel to keep carbon deposit formation in check (Chevron Techron, etc) so the use of these types of fuel has it's advantages. If you're vehicle fails emissions testing due to high NOx emissions, and all of the emission system components are functioning properly (mainly EGR)- excessive carbon deposits inside the combustion chamber may be the cause.
