Unichip + CAI FC improvement for m3 1.6 2009

**pehdehceh** · February 25th, 2013 01:34 AM

Good day to all.

Does unichip + Cold air intake for the m3 1.6v 2009 will improve fuel efficiency since it will gain additional HP thus improve power-to-weight ratio? Somehow I read on some forums that this improves FC, but it's the internet and not a 100% trust-worthy source. Please enlighten me.

Thanks in advance! :guitar:

**niky** · February 26th, 2013 12:10 AM

Yes, fuel economy will improve.

No, you won't save enough fuel to pay for the mods.

Get the mods if you want more power, but don't expect to see payback in terms of fuel savings until you've driven another 100,000 kms.

**pehdehceh** · February 27th, 2013 12:33 AM

Thank you sir for the reply.

Sorry sir I didn't quite understand what you last said. Does it mean that the mods will just consume more fuel? And what else are the probable solution in improving the FC of our m3? Will replacing the hood and trunk with carbon fiber help since it will reduce the weight of the car?

**niky** · February 27th, 2013 01:21 AM

Your economy WILL improve.

But think of it this way... you will probably gain an increase of economy from about 8 km/l in mixed traffic to about 8.5 km/l... if the Mazda3's stock fuel maps are really bad, you can boost that to maybe 9 km/l.

How much is that worth?

Every 10,000 kilometers, at 8 km/l, you will use 1,250 liters of gas. At 53 pesos per liter, that's 66,250 pesos of ags.

At 9 km/l, you will use 1,111 liters. That's 58,889 pesos of gas.

Over 10,000 kilometers, you will maybe save 7,361 pesos.

A Unichip costs 30,000 pesos. A CAI costs around 11,000 pesos.

To break even, you have to drive over 55,698 kilometers... and that's IF you're lucky and you gain 1 km/l.

More likely, you'll gain 0.5 km/l, which means you'll have to drive over 105,000 kilometers to break even.

BREAK EVEN pa lang yun.

A CF hood and trunk will cost you another 30,000 or more. And if that's your typical wet lay-up CF hood and trunk, they will only weigh a few pounds less than your stock ones. That little weight loss will not gain you any fuel economy that you can measure.

-

Want better economy? Buy a more economical car. Stuck with your car? Pump your tires up to 40 psi and learn how to drive better. Absolutely free, and high pressures and better driving can net you a 1.5 to 2 km/l improvement.

Eh di... saan ka pa?

**pehdehceh** · March 1st, 2013 12:47 AM

Wow that's a lot of computation. Haha. Sorry for having you get all that trouble.

We're still going to keep the car for a long time, and maybe we can still benefit for it as long as it is with us and reach the break even point. Haha. Isn't it dangerous to inflate the tires at 40psi?

**renzo_d10** · March 1st, 2013 01:04 AM

Can I just say this?

When you consider having performance modifications, improvement in your current FC is just a BONUS. You dont get performance mods because you want to have better efficiency, you get them because you want more power.

It's just like buying a Prius. You dont buy a 2M worth Prius because you want to cheap out on gas. You buy a 2M Prius because you want to shove onto people's faces that you're filthy rich that you'd spend 2M on a pretty much normal car. If you want to cheap out on gas, get a freaking 600k Vios instead and spend the change, roughly 1.4M on gas alone. That will STILL save you money in the long run.

I hope you get my point.

Have a good day!

Sent from my GT-P7310 using Forum Runner (wishing tapatalk is already working)

**niky** · March 1st, 2013 01:16 AM

Originally Posted by pehdehceh

Wow that's a lot of computation. Haha. Sorry for having you get all that trouble.

We're still going to keep the car for a long time, and maybe we can still benefit for it as long as it is with us and reach the break even point. Haha. Isn't it dangerous to inflate the tires at 40psi?

The "maximum sidewall pressure" stamped on the tire is typically the pressure at which carrying capacity does not increase. More pressure means more weight-carrying capacity. The actual "burst pressure" of your common 40-50 psi street tire is around 90-100 psi. For truck tires, it's way higher than that. The recommended tire pressure on some of our truck tires is around 60-90 psi, and tested burst pressure is in the 400 range!

So... 40 psi is nowhere near dangerous. In fact, some modern cars come with a recommended "maximum load" pressure and "maximum economy" pressure of around 40 psi. Door ratings for older cars suggesting 26-32 psi are simply for maximum comfort. In fact, many industry people and safety advocates recommend a minimum of 35 psi for safer travel on the highway. 26 psi increases the danger of a heat-related tire failure, especially if the tires are old.

Data from various tests suggest that 35-40 psi on car tires will net you a big gain in economy. Anything over 40-45 psi will net only small gains in economy... typically not worth the extreme discomfort you get from running rock hard tires.

And it helps improve handling, too. It's worth experimenting with, and should help you eke out at least another 0.5 km/l, unless your poor consumption is all down to the time you spend sitting in traffic with the AC on.

**pehdehceh** · March 11th, 2013 12:20 AM

Wow. I was really enlightened about that. My father told me just lately to just inflate our tires at 32 psi, which before was 35 psi. I really did notice the difference in handling with our Revo and with both of our cars I noticed that they more tend to struggle accelerating. I should tell him about that.

Thank you sir again for the information!