Chip

iTrader: (3)

Cheers mate

dojj

iTrader: (3)

did we ever get an answer then?

or does it have not a lot of consequense to your average mondeo owning pootle to the shops sort of driver?

if everything is to the limits then i can see where the slighetest difference from what it needs to be will cause a deiscrpancy, but a near 10% loss of power just because your fuel got a bit hot is a lot of power you are losing

who's to say it's not due to some other factor? how does it react out in the real world of driving up the road?

could you not simulate some back to back tests to facilitate this sort of measurement on/off the rollers?

nilrem

a bit off topic i know... but am i right in thinking that diesel works better at a warmer temperature, where as fuel works better at a cooler temperature?... im fairly sure, but thouhgt i would ask...

Chip

iTrader: (3)

Simple answer : It gives more power, but only a very small amount, not enough to really start fabricating things for your car in the hope of gaining literally a couple of bhp at most.

rapidcossie

the question you need to ask is..........How hot is the fuel actually getting?

radiant red

Suppose it can only be heated around the engine bay where it passes on its flow around the system??

As mentioned on the F1 query a few weeks back, they quoted 5 or 6 bhp increase on a slight temp drop on a 800 bhp engine.

I really have no idea how hot it gets, if it was an issue surely dyno experts etc would measure the temp when mapping etc

rapidcossie

I know hot it was in my tank and going by chips percentage calculation it was more than 2 or 3 brake.

Chip

iTrader: (3)

Bear in mind what an artificial environment it was though in terms of lack of cold airflow under the tank to cool it, so the temp difference you saw (if you measured it at all?) was probably not something you would see in the real world away from the rollers.

radiant red

Suppose sat on a rolling road its going to heat up more than general driving, i would like to see an accurate test on this subject. Wonder if stu has any thoughts on this.

rapidcossie

that may be a fair point chip.

one reason we have taken no precautions against it on the car.

Chip

iTrader: (3)

From what I recall of your car on AVA's rollers, doesnt it have a fan that is VERY well directed into the engine bay only as well, so probably literally no cold air at all directed at the tank?

rapidcossie

yeah its ducted straight on the front of my car

Chip

iTrader: (3)

Certainly going to exagerate the temperatures reached then compared to on the road.


I think a subtle and important difference needs to be drawn on this thread between trying to avoid your fuel becoming super heated, and bothering to try and cool it below ambient

rapidcossie

trying to acertain how much power is actually lost is the difficult thing.

rapidcossie

the winning time attack subaru of power station/litchfield ran a fuel cooler.

They must have thought it was worth while..

dojj

iTrader: (3)

would it not be heated along the way with the pipes running some portion along the same sort of things as the exhuasts?

Steven_RW

First person to convert the old temp gauge on the dash for fuel tank temp is the winner

RW

Stu @ M Developments

iTrader: (12)

APMSL

Back in the day it would have been you Steve. If only you hadnt had to move the instruments to get that offensively large chargecooler system in place. The good old days.

Steven_RW

LOL - u know its true stu - u know its true.

I keep wondering what the M3 would be like with a muckle great big turbo...

Im sure we could get similar power to Euans car - slightly less lag due to 3.2 litres and a wicked top speed (good gearing as std and relatively good aerodynamics) (speedo would potentially read 207mph at 8000 rpm, if it went that high lol. Its purely based on a speedo /revs and multiplied up from 6th gear.)

Anyway - i think Euan was brash to comment without detailing exact circumstances and other factors.

However its the internet and who can be arsed to write every tiny detail when its potentially a massive waste of time - cos it soon drops off the first page to be replaced by posts about novas and alloys or something lol.

RW

Benni

I'll second that mate, this thread was a little confusing until he added his input and cleared a few things up. Looks to me like Phil has come in and stirred things up a little as per usual.

Benni.

dojj

iTrader: (3)

which one is phil then

Mike Rainbird

iTrader: (3)

Would make sense if you're running a rediculously small tank like most of the time attack cars do, as the fuel would soon heat up (going by your own findings of running the car low on fuel) .

Chip

iTrader: (3)

Again, this comes back to what I was saying yesterday about it being worth trying to stop your fuel getting ridiculously hot, but its not worth trying to cool it down from "normal" temps on a road car.

ian sibbert

Surely the volitilaty of the petrol could be at the root of the power loss, such chemical components might be lost as the temperature of the petrol increases and the fuel becomes saturated (evaporated) in the tank, with that in mind better insulation of the tank would be a more prudent approach to ensure the chemical compostion isnt spoilt.

I seem to recall petrol begining to displace at about 45'C, although I think the actual boiling point is nearer the 150'C mark.....I was also under the impression new blend fuels (super Unleaded etc) evaporated sooner than older type fuels to give better performance once at the injectors, could this in an old metal fuel tank could contribute to faster evaporation?

We always insulate fuel tanks with a decent heat sheild material to avoid heat soak from the exhaust.

radiant red

Thought that would be more of a safety measure?

foreigneRS

without having a cooler, i would have thought that insulating the tank would be the last thing that you want to do as you will then never get rid of the heat added by the fuel pump (except by relying on the metal pipes running from front to back to do it, but for people who have replaced those with braided hose it's not going to be much good)

Chip

iTrader: (3)

Insulating near the exhaust however DOES make sense

ian sibbert

Insulating works both ways....you can insulate a building for instance to prevent the heat escaping (cold country) but you can also insulate to prevent the heat increasing the internal temperature (hot country)...

We do a lot of work on CO2 storage tanks with CO2 in saturated (liquid and gas state) and the solar heat gains on tanks with failed insulation is enormous....makes the refrigeration equipment work less effectively and for longer....

If you had an uninsulated steel tank imagine the effect on the saturated CO2....it would be into gas and evaporating in no time....pressure/temp would increase etc....insulating it prevents the majority of this happening, in conjunction with refrigeration equipment to control the temp/pressure of the vessel....

I appreciate petrol is a more stable than CO2 but the effects are similar...If you can keep the petrol at the temperature at which is was dispensed and you can control the temperature at source its less likely to need conditioning....

The absorbed power from the fuel pump imo would have little effect on the mass of fuel you had in a car......approx 700W versus 40 - 50 ltrs fuel....

Just another slant on the debate....

rapidcossie

My intial coment said that we noticed a power loss from heated fuel.

I didnt detail how it was heated.

You said I was talking bollocks and it would make almost zero diferance., clearly some very professional people think otherwise.

gingeRS

we do.....but thats with diesel ....i am unsure as to the effects with petrol

though we do have corrections for fuel temperature, it is very rare for an OEM to fit fuel temperature monitoring equipment

rapidcossie

specially if your new twin 3" exhuast runs close to the fuel tank

Chip

iTrader: (3)

I wasnt picturing you being stupid enough to let the fuel get VERY hot, so I do apologise for underestimating your stupidity somewhat

Again though, your comments still had NOTHING to do with cooling fuel beyond ambient which was what the thread was about, you dont seem to be able to differentiate between the two concepts.

OF COURSE its going to lose you power if you heat the fuel so much it starts breaking down or evaporating, but that doesnt mean you can gain a similar amount of power by cooling fuel that is in a normal state.
In fact if you are dumb enough to let it get REALLY hot, you could lose 100% of your power, not just 10% as you will get to the stage the car wont even run.

rapidcossie

LOL @Chip back tracking

Now admits heated fuel does make a difference

Chip

iTrader: (3)

OF COURSE IT DOES IF YOU LET IT GET *THAT* HOT!

I was wrong in my first replies, it never occurred to me that a supposedly professional outfit like AVA would ever allow that situation to get THAT bad.

You are totally correct to pull me up on it, I shoudlnt make assumptions in my posts, like assumptions companies have a clue what they are doing when designing exhaust systems or running cars on the rolllers.

I accept the for not being thorough enough with making my reply idiotproof.

Its always the way though, you think something is idiotproof and along comes a bigger idiot.

I will be more careful in future, thanks for pulling me up on it!

Stavros

I thought you WASNT keeping on and on just to win an argument?

Dont seem like it!

Chip

iTrader: (3)

Ewan brought up the subject of wether or not in my original reply I should have allowed also for VERY high fuel temps, I was just replying to him, it wasnt me that brought up that line of discussion.

Mark_w

So it seems that euan was 100% correct in his initial statement Its great how some people can comment /offer advice on the subject without being there at the time and have never carried out such testing,only adding input from what the have read on the internet or from a book

Euan,your car seems to be well sorted

regards mark

Chip

iTrader: (3)

Very good point mate.

I shouldnt have made assumptions AVA wouldnt allow the fuel temp to get ridiculously high as I never would myself, so my own experiences didnt prepare me for that scale of mistake its true.

I even commented that it was useful in diesels only cause they see temps that petrol never does, shows how wrong I was about what some people choose to do with their fuel temps!

Steven_RW

So - if u let fuel get to a certain temp (not sure how high) it could make 50 bhp difference on a 500 bhp engine? Did we just agree that?

All that we don't know, or more the case that only AVA know, is what temp the fuel got to when they happened to see a reduction in 50 bhp.

Is that about right?

Cheers

RW

Chip

iTrader: (3)

PS

Seeing as we are now apparently having to be VERY idiotproof with our replies to not have fault picked in them for lack of detail, I would just like to mention (even though to me it seems obvious)
A fuel cooler wouldnt actually help in a petrol car once you have got the fuel so hot it starts to break down and elements of it evaporate etc.