Water Injection

sdminus · Post by **sdminus** » Wed Oct 25, 2006 1:53 pm

The GTART car managed large gains with pre turbo 50:50 water injection.

Also so did the jcb diesel top speed car. With out the water it could never have made the power ( fact )

I simple terms water injection will decrease the pressure at PPP enableing you to run more boost and achieve a better BSFC, VE, BMEP for a given engine.

This is an old concept used from WW2 fighters.

Scott

duncan · Post by **duncan** » Wed Oct 25, 2006 3:04 pm

Thanks Scott- I will have a word with Zak (Mocom) when he is doing my mapping and see what the Lambda says and whether we can lean it out a little. Never say no to free power.

Yeah, Water injection again.... :-k

TonyB · Post by **TonyB** » Wed Oct 25, 2006 4:12 pm

Water injection - something I have been looking at.

Why?

Is it just for lowering charge temps? I think there is more to it but I have not establish what yet. Any info would be appreciated.

duncan · Post by **duncan** » Wed Oct 25, 2006 4:26 pm

i think it is an octane rating thing as well as charge temps

will methanol not do the same job?

sdminus · Post by **sdminus** » Wed Oct 25, 2006 4:28 pm

If there is interest in WI then maybe we should start a new thread so we can exibit info and answer questions.

Scott

Charge temps are a bit of a good side effect... At the last meet after i over shot the turning to snetterton. I arrvied at the event with a very very cold intake plenim. In fact the intake manifold froze on the way home.

It is all to do with how un efficent petrol is at absorbing heat. ( something that is all relevent to turbo cars )
Water has 9 times the specific heat capacity of petrol. ie you can replace the fuel you use to cool the combustion with it. Methanol can raise the specific octane content of the fuel. I run a race map on pump fuel becasue of this. I am leaner and have more advanced timing for this very reason.

When the combustion is cooled correctly you will find your oil temps and egt's drop also. This makes way for more and more power. TBH the limit is how much power can you fuel system and engine handle.

Scott

TonyB · Post by **TonyB** » Wed Oct 25, 2006 4:30 pm

yeah, you get extra octane from Methanol but Methanol is also a good antifeezing agent. A lot use 50:50 Methanol:Water.

This can not be the only reason tho, or I would just chuck some methanol in with my fuel!

sdminus · Post by **sdminus** » Wed Oct 25, 2006 4:35 pm

You will be able to lean right back with using water or what ever mix you like.

When you do this you will unlock hidden power in the engine.

You could un leash lots of power on a big spec car.

Scott

duncan · Post by **duncan** » Wed Oct 25, 2006 4:36 pm

a lot of people do chuck methanol in their fuel - acts as a coolant and raises octane.

http://bbs.22b.com/cgi-bin/ultimatebb.c ... 320#000013

I think I might give this a go as Mocom uses Methanol quite a lot as a home brew octane booster and enables more ignition advance iirc

duncan · Post by **duncan** » Wed Oct 25, 2006 4:38 pm

sdminus wrote:You will be able to lean right back with using water or what ever mix you like.

When you do this you will unlock hidden power in the engine.

You could un leash lots of power on a big spec car.

Scott

but i presume this would run the risk of melting pistons?

sdminus · Post by **sdminus** » Wed Oct 25, 2006 4:39 pm

With methanol you have to advance the ign timing. If you keep the timing stock you will loose power because it is a lazy burner.