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Meanie wrote:What's the difference between the K8 and the ZE?

ABout 700cc's displacement. Larger throttle body. Larger intake runners. Higher flowing heads. More air goes into the engine every revolution so that more fuel can be burned.

I laughed HARD at both of your answers, I think he meant purely from a fuel economy standpoint

Expect to use 10-15% more fuel with the ZE than with the K8, if you drive like a sane human being

Not necessarily. Its not just about displacement, its about efficiency.

The throttle regulates the actual displacement. Sure, the cylinders hold 2.5L at WOT, in certain RPM bands (called the power band), but when you're cruising, your volumetric efficiency might only be 10-15%.

If the K8 needs its VE to be 20% to maintain the same speed, there won't be much if any mileage difference.

Its all about which motor needs less air to do what you're asking it to do. Displacement is just a way to guesstimate which will be better.



But in the real world, I found my KL to only get 50km less per tank (12%) than the K8, and I enjoy shifting from 2nd to 5th.

God it feels good to be right

Averaging 26mpg on my KLZE with freed up power and some weight reduction, but also fat, sticky tires. With my K8 it was 30mpg.

Historically speaking, guys with ZE swaps got better than their K8's, hitting 500-600km on a tank easilly. Doesn't seem to be so much of the case anymore. In one MPG thread (or probably reposted that info over the years) I did a trip from Ottawa back to Niagara, driving hard, hitting over 200km/h regularly, did the trip in 4 and a half hours and still got 31mpg.

Deimos put MANY mines on his Mx-3, I think he was just short of 500'000kms on it because of his job (he has the cluster as a keepsake), and he used to get 600km on a tank regularly, highway of course.

You should also realize that most people run regular on their K8 vs premium on KLZE
Try putting running premium on K8 I bet your mileage will increase

mitmaks wrote:You should also realize that most people run regular on their K8 vs premium on KLZE
Try putting running premium on K8 I bet your mileage will increase

Actually, there hasn't been any statistical evidence to prove premium fuel increases mpg. It simply has higher octane and additives to help with pre-detonation. For a car rated for regular gas, premium fuel will get you worse mileage.

Meanie wrote:

mitmaks wrote:You should also realize that most people run regular on their K8 vs premium on KLZE
Try putting running premium on K8 I bet your mileage will increase

Actually, there hasn't been any statistical evidence to prove premium fuel increases mpg. It simply has higher octane and additives to help with pre-detonation. For a car rated for regular gas, premium fuel will get you worse mileage.

I will have to check that out myself to prove this theory correct or incorrect.

Meanie wrote:

mitmaks wrote:You should also realize that most people run regular on their K8 vs premium on KLZE
Try putting running premium on K8 I bet your mileage will increase

Actually, there hasn't been any statistical evidence to prove premium fuel increases mpg. It simply has higher octane and additives to help with pre-detonation. For a car rated for regular gas, premium fuel will get you worse mileage.

Premium fuel allows for a more aggressive tune of the motor and/or higher compression. If the ECU for the motor is smart enough, it will run as as aggressive as possible to the point before it starts to ping. A perfect example is the 3.0L Honda Accord motor that gains 10hp when running high octane fuel.

With higher octane is required when a motor runs a higher compression. Higher compression yeilds more power. the K8 runs a 9.2:1 while the KLZE is 10.0:1. Although you can't set a scientific baseline on required octane vs compression since each type of motor is designed different, you can use these as guidlines:





It's been a long time since I've read it, but this site is a good read:
http://www.daytona-sensors.com/tech_tuning.html

Higher octane itself doesn't yield better milleage, but allows the motor to run, or be designed to run, at a higher efficiency to yield more power, and with that better milleage. If the motor doesn't take advantage of higher octane, you're just burning your money away. If a motor requires high octane and you run a lower grade, the motor will compensate by reducing the timing and you'll lose power and efficiency.

For what it's worth I still think 9.5:1(KLDE) vs 10:1(KLZE) bumping from 87 to 92 octane is a joke. No matter how I look at it, a 5% increase in static CR shouldn't require a 50 point octane jump. Either the 10:1 ZE should tolerate lower octane fuel, or the 9.5:1 DE should be running higher.

my Ze runs o.k. on regular (85). But I would say it runs better on 91. Everything, start up, idle, and high RPM just sounds and feels better on 91. Milage is about the same.

Regular here is 87 octane, and premium is 92

I'm not a fan of "plus" in the slightest, I think it's a joke that they pull from both tanks and hope for the best.

MrMazda92 wrote:For what it's worth I still think 9.5:1(KLDE) vs 10:1(KLZE) bumping from 87 to 92 octane is a joke. No matter how I look at it, a 5% increase in static CR shouldn't require a 50 point octane jump. Either the 10:1 ZE should tolerate lower octane fuel, or the 9.5:1 DE should be running higher.

The K8 and KLDE are both 9.2:1. The only one that's 9.5 is the last run of KLZE.

Motors can definitely "tolerate" lower octane, that's what knock sensors and computer-controlling timing systems are for, but doesn't mean it'll give it's best performance.

Higher octane will not give you better gas mileage as stated above.. may even make it worse..
Not to mention at an extra ten cents per liter.. you have to be putting down a very significant increase in fuel efficiency to even make it worth it.