Is it worth running water injection on 9psi supercharged?

Pros & cons please.

 

"worth it" is subjective.

You know what opinions are like...

If you are NOT running an intercooler, then you will see some good things from the addition of water/alki injection. There will be less chance of detonation, the ecu will pull less timing for that reason. Another great benifit you will see from the WI on the S is that the intake manifold will be cooler when you are pushing the car, so again the ECU will not pull as much timing for that reason.

If you are running the stock ECU, and no additional engine management, or if you are not going to reprogram ie vortech black box, then again you will see good things from the WI as it will decrease the chance of detonation.

If you are running a little lean and you cannot correct it or do not want to correct it or do not even know what your A/F ratio is, then it's also worth it b/c you can add a little alcohol and make up for the loss.

There is no substitution for quality tuning, but if you are DIY guy, then it's a good back up system incase you messed up.

However, if you are already running an intercooler, on a SC'd car you will not see the benifits the turbo will see (EDIT from the addition of WI (End EDIT). the decreased intake temp post intercoler, does little in a supercharger because the the amount of air (molecules) is not going to change. BECAUSE REGARDLESS OF PRESSURE, YOU ARE NOT CHANGING THE A/F MIXTURE. However in a turbo, the decrease in manifold pressure will keep the waste gate closed and pump in more air that ='s more fuel that ='s more power.

The power increase will be made by running more advanced timing, however without a proper tune, you're shotting in the dark if your making power or hurting the motor.

Honestly, I think you'll see better HP gains by getting a proper tune and a new exhaust.

But like I said, worth it is subjective.

 

Hi Mark,

Agree with the above, it depends what you want it for? W/I is normally done for safety, with the benefit of a bit more power.

MB

 

Thanks 03spa for the reply, it is going in for a tune very soon.

My Comptech is already aftercooled, and having EMS and 550 injectors fitted, the guys doing the tuning said it might be worth thinking about water injection. I must admit I didn't understand anything they said but it sounded all good.

So it would add a little safety margin than not having it at all.



Mark, I'll have to get your mobile number and you can give me the boosted basic's for dummies.

 

Will PM you it - dont know what it is from memory though.

Have a look on www.aquamist.co.uk

I considdered it on my STi to keep charge temps down as the top mount intercoolers arent great at keeping cool!

MB