Thread: Water injection

it helps cool the immediate combustion temps which helps drop the EGT's

IT doesnt really make you any more power, it lets you make more power but it doesnt cost much power to run it if you plumb it up right, at a guess you could probably run the whole system off of a single 10A fuse.

Originally Posted by fonfe

Interesting read!
First time I've ever come across people using water/meth in diesels!
Done lots in the uk still for performance cars but that only so you can run faster ignition timing at WOT and or run a slightly higher compression on a boosted petrol engine.
Find it quite bizarre people are fitting it to their diesel 4x4s? Surely there's a lot more gain to be had with simply a bigger intercooler or if space is an issue an intercooler spray system? Just I can't see how a water/meth setup can benefit a diesel enough to warrant the cost? + is the gain decent enough to offset the running negatives in terms of power taken and power given for the setup?

It's just a high maintenance way to add fuel.
Methanol is fuel, but due to the high compression of diesel engines, you need water to prevent detonation.

I don't see the point myself. It's just another tank to fill, another system to go wrong and it can't add power beyond diesel and boost anyway.

Originally Posted by Dougal

It's just a high maintenance way to add fuel.
Methanol is fuel, but due to the high compression of diesel engines, you need water to prevent detonation.

I don't see the point myself. It's just another tank to fill, another system to go wrong and it can't add power beyond diesel and boost anyway.

Not Quite Right,
Methanol contains oxygen for improved fuel combustion.

In a petrol engine the air/fuel ratio is 16:1
in a Methanol engine the air/fuel ratio is 4:1

to me that illustrates how much oxygen is in Methanol


Water injection will also works pretty good without any methanol in my opinion.

Originally Posted by goingbush

Not Quite Right,
Methanol contains oxygen for improved fuel combustion.

In a petrol engine the air/fuel ratio is 16:1
in a Methanol engine the air/fuel ratio is 4:1

to me that illustrates how much oxygen is in Methanol


Water injection will also works pretty good without any methanol in my opinion.

Nope.

Diesels run lots of excess air. Stoich for a diesel is 14.5:1, production engines run ~20:1 (almost 50% excess air) minimum. At lower loads it can be 30:1, 40:1, at idle it can be 80:1.
Any oxygen from methanol is pointless in a diesel engine. They always run lean and need excess air for cooling (i.e stop pistons melting).

G'day guys. If you guys are really interested, check out VW's new diesel/water injection system. 300 MILES per gallon. (4 litres). Brilliant piece of kit...

Originally Posted by brettphillips43

G'day guys. If you guys are really interested, check out VW's new diesel/water injection system. 300 MILES per gallon. (4 litres). Brilliant piece of kit...

You got a link?