Water meth injection

[Head Chef]

Dave or anyone else, have you had any experience with adding water-meth injection to a supercharged S? My goal is to raise octane and lower internal temps- for more power and better engine longjevity while going to 12-13lbs. of boost.:think:

[repiv]

No experience here in this regard. You might want to contact "Sideways", "fltsfshr" or "hecash". One of them may have done something to this effect.

[desmo4]

That system was used on P-38's and other WW2 supercharged airplanes with great success.

Jonathan

[hecash]

It's outrageous. I built my own system in my first S2000. Here's the result from the first day of testing at Blackhawk Raceway. Normal laps for me were 1:29. First lap with water gave me so much torque that I did a 1:25 and eventually got it down to a regular 1:23. I was running with fully prepare BMW track machines costing 4-6 times what I had in my car and none could take me going down the front straight. It was neat to see a bunch of well-heeled exotic BMW owners gathered around looking into my motor bay after the first trial.

Here's the diagram of my final system. I got most parts, including the agricultural misting jets from McMaster-Carr industrial supply.

BTW, the reason for the right-angle configuration above the nozzle was to allow accommodation for a basket filter just before the injection.

http://forums.s2kca.com/photopost/data/15499/medium/water_injection.jpg

[desmo4]

How many sccm did feed it to get those gains?

Jonathan

[hecash]

It was a lot of volume. I was using washer fluid which is a mix of water and methanol. The pump was a 60psi demand pump to provide a constant pressure, the final misting fitting was rated at 1 g/hr. So, it's reasonable to assume that line losses were low and close to .6 g/hr flow was being realized. 1g/h gives you about 4000 ccm/hr which at 60% efficiency gives 2400 cc/hr or 40 cc/m. It nearly bogged the motor at low rpm. So, I just bypassed the manifold pressure valve switch and switched in on manually from the cockpit after I got up to speed on the track. Please double check my calculations for accuracy.

BTW, at the end of the day, my final drive broke. It was worn but the added torque applied on an exponential curve probably had a lot to do with it breaking as well.

[hecash]

I pulled the wheelwell panel on the passenger side to remove the windshield washer reservioir. I drilled a hole large enough to tap it for a 1/4 NPT barbbed hose fitting 5/16", covered the fitting and the threads with that magic plastic adhesive called "Plastic Surgery." I then mounted the pump below the reservior on a fabricated aluminum bracked that was itself mounted to the chassis using rubber grommets. The pump feet had grommets, too, So, vibration was very well damped.

I fed power to the pump from the spare "ignition switched" terminal on the fuse box under the hood and ran that hot line under the windshield washer cowling over to the pressure switch mounted in line with the intake manifold pressure line.. The bypass switch was mounted inside the center console and had and had a red light for On.

I drilled a hole into the top tube from the compressor to the throttle body and fabricated a rubber fitting to seal both sides of mount, I fed the vertical fitting that housed the filter down into the tube and screwed the hex head of the misting fitting into it from inside the tube. The mount was just after the compressor outlet. I was amazed at how fine the mist was on the first system test. It was very much finer than a hair spray mist.