I have a snow performance NA meth injection kit that I never really used besides testing it. Comes with 3 nozzles, a pressure switch and a relay lol. Im going supercharger with about 10-12psi on a stock 5.3 LS. The Supercharger is setup to run only meth injection. I plan on getting a check valve (i don't like solenoids) to keep the boost from pushing the whiper fluid back into the tank. After that Im just wondering If I need to run a progressive controller or if I should just run it to squirt 100% instantly once theres no vacuum. Boost should come on hard at 1-2psi around 1500-1800rpms and full boost in 800rpms or so.

Progressive controllers aren't expensive at like $150 I think. Just wondering if anyone has run them or if they would be needed in a setup like mine. thanks!

 

Lots of ppl run them but its up to you. Can tune around it. Size the nozzle so that it does mostly cooling and not so much fuel additive and it will be easier to tune. Blower boost comes on linear so its easy to get the fuel curve to do same via rpm curve. Nonprogressive meth will spike fuel curve rich at first til enough boost builds up to equal out the effect. Progressive tunes this spike out basically

Could just set it on a boost switch and adjust it so it comes on say 5-7 psi and lessen the effect of the rich spike

 

Thanks Orr… I feel like in the last couple of years that the forum has really dropped off.

I still might go progressive but Probably not as I don't know how to integrate it into my OEM PCM to take advantage of the boost safety feature. Ive been told to ground a really to cut the ignition or fuel pump when engaged but I don't know if I like that idea or how to really do it. I need diagrams! lol.

My snow kit has a vacuum switch supposedly rated to 15psi according to snow performance but my kit was a stage 1 NA setup but they tell me the switch is good for 15psi. So I figure I set the thing for 7psi like you said and use the medium nozzle which is a 175ml/min good for 350-525whp. ANd just shoot full spray with wiper fluid or 30meth/70water mix for the detonation/cooling properties and not so much fuel adding.

I wonder how I could set the boost switch to 7psi tho… maybe hook it up to a pressure source and increase the pressure to 7psi and adjust the switch so it activates at that pressure?

 

There should be an adjustment screw on it. I used my co2 bottle and regulator dialed to the pressure i wanted to hit and tested it that way. Had 12v from bat to switch and to a light bulb. Adjusted it til it turned on the light bulb. I calibrated all my boost switches like that

 

I have done the same thing. Just back your regulator WAY down on your air compressor or what ever's handy and use a nozzle you can slip a vacuum hose over. Regarding the water meth flow, 175ml/min sounds a little small to me. I don't remember the exact numbers off hand, but I remember in one of my turbo books they tested the cooling and detonation suppression at different rates and recommend between 3-10% water meth compared to your total fuel flow under power. On my engine I determined 5% was around 500ml/min. I have tried running less and more but since I haven't done extensive testing to find the effects of the different nozzle's detonation suppression I can't be too helpful there. I have typically been running very diluted washer fluid through mine just for some peace of mind/insurance but I still keep timing conservative enough to survive without it. With a supercharger I can see a progressive controller helping a little more than a turbo setup but at low flow rates I don't think it will matter much. I have a progressive controller but my friend is running his strictly on/off with a 500cc nozzle on a turbo LQ4. Personally I really wouldn't mind if I had a basic on/off setup on mine as well.

 

In the Turbo Buick/ TTA world we use this guy's set up.
http://www.alkycontrol.com/

It's a true progressive pump control utilizing the MAP sensor and has plenty adjustability for "tip in" psi and ramp adjustment for pump speed. So you could set it to start tipping in alky at say, 4-5 psi and then be all in by 15 psi, or tip in at 12psi and be all in at 18 psi, or whatever. No vacuum lines, no Hobbs switch. And he has the adjustment panel inside the car for changes on the fly.

He has Kits for LS platform applications too. It's not $150 kit though and that's because it's worth way more.

 

It's also upgradeable to twin nozzle, should you need more, and it can be choked down too with a smaller nozzle. It turns on and sprays around 50psi up to 150 psi so it atomizes well and there is no fear of back pressure into the methanol system. It has a filter as well. On the 3rd gen set up he uses a new coolant overflow for the methanol reservoir and adds a separate small overflow tank for coolant. It's just a well thought out set up.