Turbo intake temp
Turbo Mini Forums

il give you a clue... Co2 is used in fire extinguishers (the black ones i believe) to put out fires, as it starves fires of oxygen.

i dont belive the oxygen can be seperated from the carbon for combustion in an engine.. so its like squirting in welding gas which displaces air.

infact isnt welding gas also co2 as it stops fires/oxidisation

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Jimster and Evolution are quite accurate in their comments.
Whilst the CO2 does an excellent job of cooling down the surface of the intercooler (and therefore the intake charge), should any CO2 get into the air intake (through the air filter) the result will be a loss of power which will totally negate any benefits of cooler charge temps.
Whilst CO2 does contain oxygen it is bonded to the Carbon and so cannot be used to generate power in an engine. This is why N2O is injected into engines rather than CO2, as the N2O has a relatively weak bond which is easily broken down with heat releasing the Oxygen which can then be used to genrate more power.
At drag strips people do use CO2 to cool down their intercoolers but only prior to a run.
The easiest way of doing this is to spray it with a fire extinguisher.
Companies such as Highpower Nitrous sell a CO2 spray kit, but recommend that is is not used whilst driving due to the risk of CO2 being drawn into the air intake.
The only difference between their CO2 spray kit and their Nitrous spray kit is what the bottle is filled with. CO2 is more commonly used as it is far cheaper than Nitrous (lb for lb), although should a small quantity of N2O get into your air intake a very small gain will be made (too much N2O without matched fuel metering will result in melted bits though!).
Another interesting area is that of Propane injection.
Some people are starting to use this in place of water injection as it will allow higher boost pressure without detonation.
This has become quite common on Diesel engines but there is not much info as yet relating to Petrol engines.
It is all a question of how far people want to go.
There are different ways of generating power. TurboDave and Jimster have bhp figures in the region of 160bhp from well built engines without N2O, CO2 Spray, Water Injection etc.
You have to look at what you want to achieve and then look at the options open to you and the relative costs.
In my opinion it would be wise to look at getting a well built engine as a good starting point before looking at additional ways of extracting power from it!

Just spraying water on the intercooler can increase its efficency. I think figures suggest 10 to 20%.

The Subaru RB5 had a water spray system fitted as standard.

I'm thinking of trying spraying the intercooler with water before each run when I'm hillclimbing, would work for dragstrips too.

Wil

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Suppose i could spray mine with water everytime i park it in the kitty litter on trackdays

most people srap CO2 on the intercooler then do the run


soon as your moving the CO2 is gone

works well at cooling the intercooler and dumping the heat soak.

alex

AlexF

The trend for spraying intercoolers with CO2 at drag strips is mainly due to water being banned at most strips.
Water on the ground is good for burnouts but you don't want it on the start line.
I agree with Alex, spraying with CO2 prior to a run will minimise heat soak allowing your intercooler to be as efficient as possible.
Intercooler spray kits mean if you are too lazy to get out of the car (most of us then?) a brief button press means you can cool the Intercooler prior to your run.
Alternatively at the traffic lights on your way home from the Asda.
Quite good for frightening passers by who may think there is something seriously wrong with your car. I mean why else would it be venting smoke/steam?

many thanks for the reply re: explaining why is bad, makes sense. always good to have these things clarafied tho!

cheers,

Pete

And on the 7th day........... God created turbochargers!

very interesting lads, thanks for the mixed opinions. I seem to be at an advantage regarding co2 getting into the air intake as my cold air intake is right at the front of the car, directly underneath the indicator (mounted in the front spoiler), so the chances of co2 getting in are slimmer than when the air intake is in the engine bay itself.

A nos kit I was looking at was claiming 10% bhp gain over a stock engine and more on a tuned one......any thoughts? :cool:

NOS can give you any amount of power you want!!!!!!


alex

AlexF

sorry, I meant a nos intercooler spray, claiming 10% bhp gain - ?199 for the kit....seems quite a good price! But while we are on the subject has anyone used nos to help eliminate turbo lag. On paper this seems like a good idea, but thats probably not the case, as it would have been tried by someone by now????? ........using a nos (25 bhp) boost to help spin up the turbo and then switching off when it reaches certain revs, or boost then letting the turbo take up the momentum. I have seen...I think it was Dave? the lad in the mini mag with the t2 turbo racing at York dragstrip, and I'm sure he was running Nos....

Thanks for all your time and patience, its great to 'air' all the questions I've thought about in the wee small hours....

Dave was running nos on his turbo, but he's not any more.

I don't see how they can claim 10% power increase, as every situation is different.

If you go with those figures stated in the press, add %10 for an air filter, 15% for an exhaust, 10% for plug leads, 20% for power boost valve, youve not got loads of bhp!

Team Racing

The best antilag you can offer to a mini turbo is a well matched turbo, iegarrett T2 renault turbo one
cheers
fab