Is Water/methanol Spray Better Than Fmic?

[Dale FZ1]

Perhaps with a methanol mix, that is right. Obviously the meth combusts, which would skew the results vs using only water. I'm not going to contradict the observed experiences of guys who have used/tuned with it.

Two different approaches altogether, and would require you to use either one (100% water), or the other (water/alcohol mix) and stick with it religiously.

A friend of mine having his rally car tuned last week found that the AFR leaned off from 11.8 to 12.9 using 100% water.

[Dale FZ1]

To the original topic of the thread.

If I was going down the upgrade path again, I would probably look for a good quality SMIC to control pressure drop at higher boost, and avoid having to cut bar work to make a FMIC fit.

Then I'd also include a water/meth kit.

Overall cost would probably end up in the same bracket as using a good FMIC, but the results of the water/meth kit superior.

The question would be can you live with checking/filling the reservoir on a regular basis?

Edited March 4, 2007 by Dale FZ1

[T04GTR]

this one looks the goods.

[r33_racer]

Yeh when ours was tuned they had to lean out the afrs a little....but then screw in heaps more timing and a few pounds extra of boost and watch the power climb with no increase in knock.

[T04GTR]

cool. as soon as i get my new alcon setup happening il be going down that path. seeps pretty good bang for buck.

also i would think thered be a slight reduction in turbo lag too. is this tru. cos of more stuffs going into the engine?

[BAMR33]

this one looks the goods.

That kit does look fairly decent, I'm guessing after currency and post it would be around $800 too.

[StockyMcStock]

question for you guys: how long are your actuation paths for the water/meth kits?

I am probably going to install a decent kit on my vehicle eventually, but the reserviour would need to be in the boot of the car due to space constraints under the bonnet. would 2-3m of piping be okay? do they have check valves?

[Cubes]

Stocky,

If you check out a couple of the links above there's a bloke with a kit behind his back seat. So I'd assume its all fine running a setup so far away. You can get check valves for them. Not sure if the kit includes it.

[gnki'vlct]

lol

"just run methanol"

[r33_racer]

haha neill we run our tank right at the very back of the car in the driver side quarter panel/boot...no problems with ours. Its small quarter inch line with a high pressure pump...there is virtually no pressure loss over the few metre distance it covers, if your suspect about it just get the upgraded pump to the 220psi model.

Ive heard of some bloke who set his injection up two way...one feed before the throttle body as per standard and then he hooked up another one in his intake which was hooked up to a boostline from the plenum so it helped atomise the mix better and it cooled the compressor/intake air before it was cooled by the i/c and then even moreso when it reached the valve inlet. Supposedly it increased the hp rating of the compressor by another 100-200hp as it was cooling the intake charge right at the turbo inlet so its efficiency range could increase without blowing hot air...thats how it was explained to me anyway...ive never seen it myself....but i wouldnt mind trying it.

[BAMR33]

Yeah, I read somewhere having a nozzle before the compressor helps cool the intake charge heaps better but can also cause wear the compressor blades down if the mist isn't fine enough.

[r33_racer]

yeh thats why you hook up a pressure line to help atomise it.

[Abo Bob]

So would I be right in assuming that you need some available headroom in your turbo? I mean that my turbo is already maxed out so will my only gains be made with timing?

[r33_racer]

yeh more then likely. But extra timing adds a bit of power. If your knock is a little high at that level then it will come in handy just for reducing knock.

Edited March 5, 2007 by r33_racer

[BAMR33]

I am thinking of just buying a 100psi pump, a proper spray nozzle and using the signal from the stock boost solenoid to activate the water injection at 4500rpm via the use of a relay.

Anyone have any thoughts on this idea? I know it gives limited scope for tuning abilities, but it would reduce some of heat generated at higher boost levels.

[Busky2k]

I have a kit imported from the US. Works well however you need to tune around it. If you do not have access to a wideband then you are tuning blindly.

Btw water's effect on AFR is negliable and that is a fact.

[Dale FZ1]

I have a kit imported from the US. Works well however you need to tune around it. If you do not have access to a wideband then you are tuning blindly.

Btw water's effect on AFR is negliable and that is a fact.

Total agreement about the need to use wideband to tune.

Regards the effect on AFR, can I refer you to my earlier post about the impact on my mate's rally car during tuning? Going from 11.8 to 12.9 is quite significant. Note: that particular system used only water injection - no intercooler.

When tuning "around" the water injection, did you play mostly with fuel, or ignition?

cheers

Edited March 5, 2007 by Dale FZ1

[r33_racer]

well the kit we use states that you need to lean out the mixtures by around 10% i think it says from memory. Apart from the kit, our tuner also stated that he had to lean it out as it was too rich and flat spotting if he didnt.

[Dale FZ1]

Michael, you're using a water/meth mix though - correct?

[rev210]

water/methanol kits are as old as the hills and they don't cost a fortune to make yourself if you have the time and can be bothered.

You 'can' remove the air to air intercooler if you are drag racing and just the injection kit but, you might also like to switch instead to a water/air intercooler.

Tuning wise you end up with an interesting mix of changes depending on whether you used the kit to nab more boost, timing or leaner AFR or the usual combination. From memory (although someone correct me if I am wrong) the 'ping' threshold is lower with the water injection effectively acting better on hot spots in the combustion chamber as opposed to an air temp drop of equivalent magnitude (waters specific heat value is rock & roll compared to the gas components in air). I vaguely remember conversation (alcohol and years of brain damage) with drag racers years ago at the old ravenswood drag strip about humidity and it's effects on the tune for supercharged engines.