New RX-7 or 2008 RX-8?

Rumors have been circulating around the internet and other sources that Mazda plans on releasing a new rotary by 2008/2009. Some have said that it will be newly designed and will be revealed towards the end of the year, and most likely the RX-7 replacement.

Review: Shell V-Power vs SPC 98 Petrol / Prestone Octane Booster

Who says fuel doesn’t really make a difference? I’ve always been using V-Power as past experiences tell me that the car feels livelier and more torquey with that brand of fuel than any other brand in the market. In general, Shell V-Power is smoother, provides better linear acceleration, and definitely seems to provide the power when you need it (pedal to the metal).

Just a couple of days ago, as i was running out of gas, i went into SPC to pump their 98 octane fuel. And boy was i disappointed. Compared to Shell V-Power, SPC 98 is:

• rougher and noisier – revs are much louder now
• the car seems to be out of breath, especially in low to mid torque
• exhaust emissions smell a little better though, V-Power smelled awful
• cheaper

This then begs the question….why? Well, i think it boils down to additives in the fuel, and the amount of hydrocarbons packed per unit of fuel. Premium grades of petrol often contain more energy per litre due to the composition of the fuel as well as increased octane. A simple explanation is the carbon bonds contain more energy than hydrogen bonds. Hence a fuel with a greater number of carbon bonds will carry more energy regardless of the octane rating. A premium motor fuel will often be formulated to have both higher octane as well as more energy.

The power output of an engine depends on the energy content of its fuel, and this bears no simple relationship to the octane rating. A common myth amongst petrol consumers is that adding a higher octane fuel to a vehicle’s engine will increase its performance and/or lessen its fuel consumption; this is mostly false—engines perform best when using fuel with the octane rating they were designed for and any increase in performance by using a fuel with a different octane rating is minimal.

Using high octane fuel for an engine makes a difference when the engine is producing its maximum power. I’ll stick to V-Power

Review: Prestone 0 to 60 Octane Booster
Since we’re talking about fuels here, might as well do a short review of the Prestone 0-60 Octane Booster as well. One word of advice – NOT. The nice packaging and nifty artwork flames hides a completely useless and potentally cat-unfriendly product. The 10 points of octane increase is really only 1 real octane number as 1point = 0.1 octane rating. When i put this in, the car was slower – Gtech runs were about 0.5-0.8 slower in the century sprint. Now i know that this could have been an anomaly, but the coincidence and ‘butt test’ was compelling – the Prestone Octane Booster does NOTHING for performance, and in fact decreased performance. Also, i’m sure we all know how any fuel additive is potentially harmful to catalytic convertors. For those that really want a boost, mix in toulene/zylene or go raffles marina get ELF speedboat petrol