Fitted the PA FMIC last weekend and i'm running the standard turbo ( although an upgrade is in the pipeline soon )
My concern is that since changing the standard intercooler i've noticed the fuel gauge going down quicker than normal! LMAO
Should that be like so??

The reason for an intercooler is obviously to cool the air, cool air is denser

An engines power is determined by the amount of air and fuel it can consume

as your new intercooler is cooling the air entering the engine better than the original one the air entering the engine is denser, if it run like that with no adjustment to the fueling then it would run lean

so in short as you now have denser air entering the engine as a result of a better intercooler you will need more fuel to sustain the correct AFR.

So yes that's to be expected

has your right foot got a bit heavier

More oxygen SHOULD mean better burn and less consumption.. Still I've noticed the same thing.

The car was off the road for 6 months ( due to a driving ban ) so i do think my right foot has got alot heavier!:D



That explains it then i guess..nice one!
A Flea map might be in order when i get my hands on a bigger turbo.

what are you talking about?

If you have a given amount of air then you need a given amount of fuel to maintain the desired AFR

hence stoich being 14.7 to 1 meaning 14.7 parts air to 1 fuel, that's for petrol at least and with different fuels it changes


High performance turbocharged engine while on boost run rich, anywhere from 12 to 1, to as rich as 10 to 1, there many reasons for this pretty much all for safety reasons, while an engine is cruising and a turbo charged engine is not on boost you can run lean, often called lean cruise

this is one time where it is safe to run lean as the engine is not being stressed or worked hard, how lean you actually go is dificult to answer and can only really be asertained buy mapping and testing with the opropriate equipment like det cans.

In many cases where a much larger and lagier turbo has been fitted you find that at motorway speeds or cruising you can have much better fuel economy, the reason for this is that because the turbo is not on boost till much later in the rev range you will use less fuel as the turbo is not providing as much air as it used to at that given point, obviously once you up the flow and boost you will use more fuel than you did before as the larger turbo will provide more air and as such power


It's swings and round about but you will never be able to have your cake and eat it, although there many tricks along the way to gain some effiencies, eg head work and lighter rotating parts

Ricky

Yeah.. What about you mate..?

i think what ricky is trying to say is that the ratio should always stay the same so more air means more fuel. less air means less fuel.

I think turbo nick summed it up nicely..Thanks everyone.
More air in more fuel used. Less air in less fuel used.
Guess I'm going to have to re learn my right foot a few tricks!

Colder air means air more dense with oxygen, which means better burn, which means more power, which means you don't have to floor it as much. Hence less consumption! Or there should be anyway?

Nick summed it up well

Per, it does not just make oxygen in the charge denser, what enters the engine is what's in our atmosphere, I'm sure you know that there is more than oxygen in our atmosphere, it makes all of it denser so more of it can fit in the same space

That’s not what per said, the thread says more air means more fuel yea? So we all no more air+more fuel means more power?, so less right foot to make the same power as before the increase in air and fuel.

With a more effiecent intercooler thr turbo can now cram more air charge in to the cylinder as it's denser, so for a given amount of boost/flow it will make more power

if it's more powerful then it will to use more fuel

if you are easier with the acclerator then your metering power and keeping it low so yes it will use less fuel in that situation


That's the same with the original setup also

that's an effiency in the driver not the engine and will change from one day to next, dependent on route and mood

So - in effect if you're driving normally, in your normal speeds, the car will consume less. Because of better burn. Yes?

No, I think not


Your trying to quantify something that is completely unreliable and un scientific


In effect you upgrade the intercooler to improve charge temps and in turn the turbo can cram more air into the cylinders, more air means more fuel


If you drive it more econmicly then yes it will be better on fuel but that has nothing to do with the intercooler that's down to driving style



It's not that complicated, look at it this way

stick the car on the dyno in 4th gear at 2000 rpm, lets say for arguments sake at that point it's producing 4psi of boost

now fit the intercooler and do the same thing, because the air charge is cooler at the same point and boost more of it is entering the engine so in turn it must be using more fuel, that means more power and less fuel econemy

obviously if you lower the rpm in the second run with more effiecent intercooler you could use less fuel but because you fit a better intercooler does not mean you drive everywhere slower


The intercooler has been fitted for performance reasons not economy

Now that I'm running the correct tire pressure I can safely say it's more frugal than before. Drove to Sthlm (500km's) and back, so I had wind in both directions. Mostly highway and 140km/h-160km/h.
I had 8.3l/100km one way (record!) and 9.1l/100km back.
So, an average of 8.7l/100km with 320hp and very fast cruising!

What modern car today can match this..??

Before Flea's remap and FMIC, I think I'd have around 10l/100km or just over.
It's possible my new Plus-kit helps too, but not much I think..