K&N Typoon Has Increased Mpg!

[Jiberjaber]

Well after 15K miles my lex has averaged 29 mpg. I have used in excess of 2100 litres (my records were restarted at 2k5 miles as I lost the spreadsheet then.

This is with a mixture of Optimax, BP SUL, Sains SUL and BP/Sains UL.

[aido]

That's well impressive mate, have to admit looking at your figures that I felt some extra poke from the Esso Super Unleaded than I do with Optimax, guess you only did the one tank full but I found their stuff to be excellent!

[eXOBeX]

Just ordered a K&N Typhoon. Bought on eBay, then spotted it almost a tenner cheaper on his website. Bugger!

[lexicon]

The IS300 will always return better MPG over a long run than the IS200 since the Power : Weight ratio is higher - means less fuel to move more metal.

I think you're defying the laws of physics there :o

I've seen you post before about this, so maybe it's just the speed that you drive at that gets you better mpg (or perhaps there was something wrong with your 200).

I saw the Autocar tests too and I don't see how they could possibly have got a "test" figure of 26 - their data is full of mistakes/typos.

My own experience is;

75000 miles in IS200 (manual) - Best=34, worst=26, overall average=30

20000 miles in IS300 - Best=32, worst=25, overall average=28

Both unmodified (except the 300 has a K&N filter).

One thing I have noticed is that the 300 is much less "speed sensitive" - doing anywhere between 60 & 90 makes little difference, whereas you could get much better out of the 200 by cruising slowly.

[MrADeveci]

Just ordered a K&N Typhoon.  Bought on eBay, then spotted it almost a tenner cheaper on his website.  Bugger!

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That's where I bought it from ! .......... eBay that is ...... ;)

[eXOBeX]

Had an email back. As I guessed, the extra tenner gets swallowed up in eBay fees! Still, happy bunny.

[gib]

After all the "claims" that the induction kit increases MPG ................ I tried it yesterday, somewhat 1,000+ miles after installing it ............ and it has increased !

Before the K & N I was getting 325 miles on a full tank (both town and motorway)

Now I get 370 miles to a full tank !

So it does actually increase MPG .......................  :D

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Can someone tell me what the theory is - why, would the engine use less fuel with a better air intake?

Quite fancy one of these....

[javadude]

Hey this means I can justify getting an induction kit. Anyone know if getting a fatter exhaust improves mpg too? :D

[Mr Morse]

In theory:

The most restrictive part of an engine is the exhaust system and the engine's ability to breath effeciently. Therefore, for two similar vehicles, one fitted with the standard kit and the other fitted with an unrestricted exhaust and induction, provided the two vehicles were driven under identical driving conditions, the unrestricted vehicle should return better MPG.

[javadude]

Yay sounds good. That'll do me. Thanks :D

[SHAHZ]

Yay sounds good. That'll do me. Thanks :D

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your too funny mate :)

[AMH]

Javadude - your not "still" trying to justify the 'zorst are you - come on - just get it done ...

QUESTION: Does the ECU cope with the increased air flow of induction kit and replacement exhaust or does the car then run too lean, eg on motorway? (Edited by javadude and put back paraphrase of bit I lost. sorry. what a muppet)

[javadude]

Aaarrgh. Sorry AMH I seem to have hit edit and messed with your post instead of clicking reply.

Javadude - your not "still" trying to justify the 'zorst are you - come on - just get it done ...

lol :D Actually I can't afford it yet anyway as we need to get some work done on the house. After that...

[MacRS200]

The correct air:fuel mix is 14.7:1 see here so the more air that goes in the more fuel that has to be injected to keep it balanced. This done by a combination of measuring the amount and temperature of the air going in and the level of oxygen in the exhaust gasses.

Also power is directly proportional to the rate of (efficient) burning of fuel.

So I think that the better MPG is more down to driving style with the K&N fitted rather than the filter/induction on it's own.

[AMH]

Javadude - no problem - I thought I was the only one to mis-edit ... !

MacRS200 - thanks - so the ECU will compensate up to the limit of the injectors size - seems to make sense now - hence rolling road to check mixture across rev range and to match injector size with mods.

Thanks.

[johnboy]

In theory:

The most restrictive part of an engine is the exhaust system and the engine's ability to breath effeciently. Therefore, for two similar vehicles, one fitted with the standard kit and the other fitted with an unrestricted exhaust and induction, provided the two vehicles were driven under identical driving conditions, the unrestricted vehicle should return better MPG.

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since fitting my PROLEX kazama tailpipe the car definitley accelerates better and it appears at the moment to actually be a little better on the MPG.

wil let you know when i fill up again

induction kit next hopefully

john

[ColinBarber]

The correct air:fuel mix is 14.7:1 see here so the more air that goes in the more fuel that has to be injected to keep it balanced. This done by a combination of measuring the amount and temperature of the air going in and the level of oxygen in the exhaust gasses.

Also power is directly proportional to the rate of (efficient) burning of fuel.

So I think that the better MPG is more down to driving style with the K&N fitted rather than the filter/induction on it's own.

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The 14.7:1 ratio is the best mixture for the cats to work, however you need to be in closed loop mode for that to work. At other times the ECU is using it's pre programmed mappings to do the fuel mixture. If you make the air intake a little less restrictive then you lean out the mixture slightly which is one of the reasons you see an increase in mpg. This isn't too much of a problem with Toyota engines as the are normally set up to run a little rich anyway.

However when you start altering the intake and exhaust it is a good idea to get the car on a rolling road to see how the fueling is. There could be a point in the rev range where the engine is actually a bit lean which is not a good thing.