Petrol

[Matt]

Is it normal for a 3rd gen to smell quite strong of petrol whilst the car is idle.

Also i get about 75 miles out of £30 of super unleaded around town, is this about right?

cheers

[Fish]

Matt, when cold they do run rich, very rich.

Sounds about right on the MPG, later models should be a little better due to better ECU\'s. I get somewhere between 175 and 230 miles to a full tank. Mixture of town and motorway driving.

Dan

[Matt]

thats ok then sounds about the same as mine i got about 150 miles from 50 quid and that was caining it a lot.
how many litres does a full tank hold is it 60?

[johnf]

Not sure i agree with your MPG being OK

If petrols about 78p ltr - is that x 4.5ltr per gallon = £3.50

In that case £30 = 8.6 gallons

75 [mls] divided by 8.6 = 8.7 MPG - This would be the lowest MPG I\'ve heard of.

Have I got the maths wrong?

[Matt]

i calculated the mpg on a website and it worked out about 11mpg

[J4P RX]

At last someone else is reporting MPG as low as mine!

I got less than 200 miles off my last tank (full).  That was a bit fast though.

Around town I got about 80 miles from 30 quid last time.

I had my car on abeeys dyno - it is very rich apparently

Cheers
Lee

[Matt]

yeah same as me, im glad im not the only person thats constantly in the petrol station

[J4P RX]

Im soon going to get a Power FC or similar - I recon it might increase my lousy fuel economy.

I was expecting it to be bad but 11mpg is much worse then I prepared for!  

I hate driving it and after ten miles (nothing really) thinking well there goes another £4!  (well ok £3.50)

Cheers
Lee

[Matt]

yeah its worse than i expected, whats this power FC

[J4P RX]

Ill do a poor job of explaining so it might be easier to read this...

http://www.ejperformance.com/site/popups/powerfc.php

My car also smells of fuel at idle too, I did forget to mention that.

Cheers
Lee

[Matt]

cheers mate

[Fish]

Later model FD\'s (post 95) have the 16bit ECU, which returns better MPG than pre 95 models (8bit ECU).

Aftermarket ECU\'s like the Apexi, Motec, Haltech, Wolf, Microtech, etc. will/should return better MPG as they will be better mapped to your car. The more exotic ECU\'s like the Motec for example will also have whats called closed loop lambda, what this is, is when cruising down the road the ECU works out what and how much fuel is needed to run the car without causing problems. I have used the Motec before and on motorway runs, I was returning a lot better MPG than normal driving, due to staying within the C.L.L. area\'s are letting the ECU work it out for me.

Time spent mapping these aftermarket ECU\'s is money well spent.

Dan

[Matt]

Is there anyway of telling what ECU i have?

[johnf]

The question as to the benfit of these aftermaket ECU\'s must surely be set against the cost of installation for the projected fuel saving.

I have no idea what they cost or what % inrease in MPG could be expected.

I would like to work out how many gallons it would take to recoup the initial outlay. Are there other benefits to these units?

Just another thought, if the RX8 has managed to retain the engine performance with much better MPG would I be able to buy a new RX8 engine and would it fit in my 3g 7 ?

[J4P RX]

Something like a Power FC if mapped properly should be able to give you a significant increase in power too.  

The FDUK RR day at G-Force showed that all the people who had a bit of power had pretty much gained it with a power FC.  I wouldt do it just for economy, but more to ensure my engine was running correctly and safely etc.

Lee