2015 Kia K900 V-8 Long-Term Update 1
Testing Real MPG on Regular and Premium Fuel
Daily driving a 2015 Kia K900 V-8 has its perks, but if there's one element of ownership I would magically change, it's the fuel economy -- or the size of the fuel tank. It has nothing to do with the price of gas, but rather how much my time as a $66,400-car-driving commuter is worth. While expecting 30 mpg from a car as big and powerful as the K900 is ludicrous, it's difficult to avoid the Kia's bottom-of-the-pack fuel economy, and, more important, overall driving range. There's nothing luxurious about spending more time than necessary at gas stations unless you own a 12-cylinder luxury car, in which case you should pay someone to refuel for you.
So just how good is the K900 V-8's fuel economy in the real world? We Real MPG tested the Kia on regular and premium gas to find out whether we'd see a difference.
A recent trip to Laguna Beach put the fuel economy/driving range issue into perspective. With four people enjoying the Kia's quiet cabin as we inched down the 405 freeway, I wondered at what point during our weekend getaway I would once again be filling up the car. The K900's full-size competition might be far more expensive, but whether the cars come with a six- or eight-cylinder engine, their fuel economy and overall driving range have the Kia beat. The K900 V-8 is EPA-rated at 15/23 mpg city/highway on premium gas with a 356-mile driving range based on the EPA combined mileage figure and the car's 19.8-gallon fuel tank. The 2014 Lexus LS 460 L is good for an EPA-rated 16/24 mpg and a 422-mile driving range, while the six-cylinder BMW 740Li gets 19/29 mpg, has a 464-mile driving range, and will reach 60 mph from a standstill in around 5 and a half seconds. The eight-cylinder BMW 750Li still has the edge on the Kia in EPA ratings, as does the segment-leading Mercedes-Benz S550, the Audi A8 L, and in fuel economy, the six- but not eight-cylinder Jaguar XJL. No one can take away from Kia's boldness in introducing the attractive K900, but we'd point to fuel economy and driving range to anyone who says the car is a direct match in every way for large cars costing far more money.
When we handed over the K900 V-8's keys to the Real MPG team, two tests were conducted: one with regular fuel and one with the car's recommended premium. After RTFM-ing, I learned that Kia allows the use of 87-octane gas, but notes 91-octane gas will yield "improved vehicle performance." With minor tweaks, Hyundai uses the same 5.0-liter V-8 on the Genesis sedan, which allows owners to use regular gas if they're willing to sacrifice 13 hp and 11 lb-ft of torque compared to what they'd get with premium fuel. Though the Kia K900 V-8's specs vary slightly from those of the Genesis V-8 and Equus, we were still curious to see what effect using regular fuel would have on fuel economy.
It turns out not much changes, at least on the K900's naturally aspirated 5.0-liter V-8. Compared to EPA figures of 15/23 mpg, the K900 V-8 got 14.6/24.1 Real MPG and a combined 17.7 Real MPG on regular fuel. Results with the recommended premium gas were so close that the difference was statistically insignificant. The K900 V-8 got 14.7 Real MPG in the city and again beat the EPA estimate on the highway, with 24.6 Real MPG. The combined 18.0 Real MPG figure suggests your fuel economy might not vary greatly if you ignore Kia's recommendation to use premium gas in a K900 V-8.
In future updates, we'll explore the performance of the K900 on regular and premium gas, and plenty more. For now, I'll have to accept that part of the driving experience of this respectably executed luxury eight-cylinder sedan is visiting gas stations a few more times per year than others in its class. Considering how much more those sedans cost, however, some could argue it's a small price to pay for all the K900 offers.
More on our long-term Kia K900 V-8 here:
|Service life||2975 mi|
|Average fuel economy||18.4 mpg|
|CO2 emissions||1.05 lb/mi|
|EPA City/Hwy/Comb Fuel Econ||15/23/18 mpg|
|Energy consumption||183 kW-hr/100mi|