Water Injection Question
Water Injection Question Tossing my car on the dyno at the end of the month and want to have the option of spraying at least windshield fluid if needed. Car's never had WMI on it, but overthinking things now 
I have a devilsown pump and 14pgh nozzle, can one spray too much and do more harm than good? If so I will buy a 7gph nozzle, but would rather not buy stuff I don't need to.
I have a devilsown pump and 14pgh nozzle, can one spray too much and do more harm than good? If so I will buy a 7gph nozzle, but would rather not buy stuff I don't need to.
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FWIW , I run a 10gph nozzle with 50/50 mix on a 6L -- no issues . 14 gph of 70/30 water/meth might be too much water and cause a stumble if activated at low rpm , someone with that size nozzle will answer hopefully. Having another nozzle handy for your dyno session is probably not a bad idea and not too expensive - good luck
Yes, you can easily hurt power with water/meth. It's not really made to gain you power. As I've said a million times... it's not an intercooler! Think of it more like running race gas. If you don't change the tune-up, it's not going to do much, and can actually hurt performance. I ran identical times with 10gph of washer fluid on VS off. In actuality, it likely hurt performance a tiny bit. But when reading the plugs, the pass the pass with the W/M read much cooler. Meaning I could likely add timing/boost. I prefer the safety margin and cooler plugs over the couple HP I may have lost. This was at 23ish lbs and running high 8's around 158.
It will never work as well as an IC, but to see actual "intercooler like" performance gains, you need to spray straight meth and ALOT of it. Then adjust the tune to compensate. Bigger gains can be seen if you spray pre turbo. (assuming no IC).
It will never work as well as an IC, but to see actual "intercooler like" performance gains, you need to spray straight meth and ALOT of it. Then adjust the tune to compensate. Bigger gains can be seen if you spray pre turbo. (assuming no IC).
Last edited by Forcefed86; Mar 8, 2021 at 07:46 AM.
Hurting power is fine, hurting pistons is not. Not looking for fueling or timing boosts, just a added safety blanket if its needed.
Car has run for at 18*, 15psi for a couple years, but I never knew IATs so now trying to do things "right"
Car has run for at 18*, 15psi for a couple years, but I never knew IATs so now trying to do things "right"
You also need to factor in pressure. As the GPH nozzle rating is at 100 psi. Also you have a pressure screw on your pump you can adjust. IMO with your boost/timing the 7gph is a better place to start if your spraying washer fluid.
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Verdad Gallardo Sure, you can run the larger nozzle and less PWM. Basically lowering volume sprayed via pressure. But know the higher the pressure the better the atomization and the better the distribution. If using standard -20 washer fluid (all I can find here in KS). 7gph is plenty IMO. Its all I ran on my intercooled E85 setup. As you up the methanol % you can up the volume a little. But a little water goes a long way and too much can cause ignition issues and power loss.
Alright, I'll stick with the 7gph nozzle and maybe give it a small soft start via pwm.
My thought is if the tune is safe without spraying anything, adding in 7gph will only help the motor. As long as I don't blow out spark.
My thought is if the tune is safe without spraying anything, adding in 7gph will only help the motor. As long as I don't blow out spark.
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It kind of goes by HP when it comes to picking the right nozzle. 10gph is good for about 500-650hp. A 7gph is probably maxed out by 500.
I ran a 10gph nozzle for 17psi from a s475 on a 5.3 and put a second nozzle in this winter for a combined 15gph.
You would have to have something go terribly wrong to crack a piston or anything with it. It's not going to crack from the spray but only if you managed to spray so much in that it hydro-locked the motor or just pushed the compression psi off the charts from so much liquid volume.....that's basically impossible. Even if you had no nozzle restricting the flow from the pump, I don't think it pushes enough volume to ever, ever do that.
PWMing the ramp in doesn't really change much of anything from my experience. The ramp in effect is only controlling about 10-20% give or take. The things basically kick on with a minimum of 80% capacity because they still have to deliver the liquid it at high pressure. So it's not like it starts a 7gph nozzle at 1-2gph and ramps it to 7...it starts it at about 5-6gph and ramp to 7.
Most setups do no like it early. You need to have some decent heat in the intake to make it evaporate instantly. Over 100F for sure, more like 120. Mine hates it before 10psi and absolutely must have it by 14psi, i only run 90octane though.
You might hurt power until you add in some timing or a few more psi of boost, but don't worry about it hurting the engine. If anything after you run WMI for a while it cleans the inside of the engine and intake so good you'll swear its a new engine. The entire inside of mine is dyed blue from washer fluid i use lol.
I ran a 10gph nozzle for 17psi from a s475 on a 5.3 and put a second nozzle in this winter for a combined 15gph.
You would have to have something go terribly wrong to crack a piston or anything with it. It's not going to crack from the spray but only if you managed to spray so much in that it hydro-locked the motor or just pushed the compression psi off the charts from so much liquid volume.....that's basically impossible. Even if you had no nozzle restricting the flow from the pump, I don't think it pushes enough volume to ever, ever do that.
PWMing the ramp in doesn't really change much of anything from my experience. The ramp in effect is only controlling about 10-20% give or take. The things basically kick on with a minimum of 80% capacity because they still have to deliver the liquid it at high pressure. So it's not like it starts a 7gph nozzle at 1-2gph and ramps it to 7...it starts it at about 5-6gph and ramp to 7.
Most setups do no like it early. You need to have some decent heat in the intake to make it evaporate instantly. Over 100F for sure, more like 120. Mine hates it before 10psi and absolutely must have it by 14psi, i only run 90octane though.
You might hurt power until you add in some timing or a few more psi of boost, but don't worry about it hurting the engine. If anything after you run WMI for a while it cleans the inside of the engine and intake so good you'll swear its a new engine. The entire inside of mine is dyed blue from washer fluid i use lol.
I actually measured pressure VS DC and it changed quite a bit on mine. There is a formula to calc nozzle flow rate VS pressure as well. Here's my little cheat sheet. I used a cheap shurflow pump too. Only had 155-160 max PSI. Pressure and calcs based off 2 10GPH nozzles (rated at 100psi). I spray pre-turbo. NO IC.
I run E60ish fuel. and anything over 65% or so on DC causes ignition issues. I ramp it in from 8lbs to 19lbs. (1gal washer fluid and 2 bottles of heet, should be close to 50/50)
Also, if I ramp it in too quickly it lugs the motor down. Which I ended up using as a form of traction control. I ramp it up to 50% quick, then drop 25% out of it, then bring it back in. Works really well! (street car only)
* Flow is calculated, I only measured pressure. *
I run E60ish fuel. and anything over 65% or so on DC causes ignition issues. I ramp it in from 8lbs to 19lbs. (1gal washer fluid and 2 bottles of heet, should be close to 50/50)
Also, if I ramp it in too quickly it lugs the motor down. Which I ended up using as a form of traction control. I ramp it up to 50% quick, then drop 25% out of it, then bring it back in. Works really well! (street car only)
* Flow is calculated, I only measured pressure. *
Last edited by Forcefed86; Mar 12, 2021 at 01:50 PM.
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Yes, it works just fine. Many of us are running W/M and no intercooler. I run boost juice. It isn't to make more power..,it is to keep your engine nice and happy. Problem is tha tmost people see everything in HP figures......I see it in how long can I have my hot rod and not hurt it. Having a fast car this one time at this one place with this one setup doesn't mean much. My BMW runs it...my turbo fox coupe runs it with no intercooler and my procharged c5z runs it with no intercooler.
I plan on not running an IC'er at first, 93, and was looking into W/M, not going to be a high boost deal, but running an LS6 intake, wonder how good cyl. distribution is, you figure it is made for air (prob where an IC'er shines).
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Nothing outside of boost-juice from snow is 50/50 mix. I'm in Alaska and as weird as it sounds, there are concentrations of washer fluid that you can legally only sell and buy in Alaska and Canada. The -40 stuff from Kroger/Fred Meyer is the highest methanol content I can find out of a store, again, that wasn't snow performances boost-juice. But it's only for sale in AK and Nothern Canada.
The -40 stuff is 40% methanol
the -30 stuff is in the 30%
and the -20 stuff is around 10%-15% methanol.
You can get 50% methanol content out of a gallon of -40 with one bottle of Heet in it. I think the -30 stuff comes out to about 40%-45% with a bottle of Heet.
Safe concentration is 49%. After that, the **** becomes flammable when spilled.
But honestly there is no big difference I could tell until you put the -20 stuff in and then it's not enough methanol in it. Anywhere from 30%-50% evaporates fine and that's what you're going for, the efficient evaporation of the fluid, not it's energy content.
I can tell by the blue dye on everything inside mine that the distribution probably isn't super even going into the runners. But I'm writing off any unevaporated W/M and odd distribution as only when the throttle slams shut after a pull with it spraying. Some liquid is bound to get caught up in there and stay in liquid form. But the whole purpose of the W/M is just to suck the heat out of the air charge and it does that equally to every cylinder. I can't find anything on the plugs that would indicate anything weird going on between them.
Typical volume kits do most of their work in the cylinder, pulling heat and slowing the flame front down to help prevent detonation. This is why you see little to no performance gain w/ typical W/M alone. It's very similar to running higher octane fuel. Dumping some 110 in your tank isn't going to do squat for ya performance wise if you don't up the boost/timing to go along with it. So IMO, it's pretty darned important to at least try to get the distribution even. And the factory intakes are **** poor at that job.
Ideally you'd want a "wet flow" single plane carb style intake for distribution. And to spray a mega ton of straight meth in the turbo inlets. If enough volume was sprayed, you could achieve an intercooler like effect, up the turbo efficiency, and a large octane boost. It would also be finicky to tune and a fire hazard. But it has been done with great success.
Now I'm not saying it won't "work" With a factory intake. That's how I ran it as well. Just have to realize the limitations and read the plugs. Also helped that I had an ECU that could add or subtract fuel to cylinders individually.
I run a SBC single plane intake so I have that going for me.
I just was going for added safety while running pump 93, not looking to gain power via additional timing gained from spraying meth
I just was going for added safety while running pump 93, not looking to gain power via additional timing gained from spraying meth
I don't agree. The typical volumes sprayed do VERY little for the air charge temp's as a whole. This is easily seen by the HP numbers basically doing nothing with the W/M on/OFF on the dyno.
Typical volume kits do most of their work in the cylinder, pulling heat and slowing the flame front down to help prevent detonation. This is why you see little to no performance gain w/ typical W/M alone. It's very similar to running higher octane fuel. Dumping some 110 in your tank isn't going to do squat for ya performance wise if you don't up the boost/timing to go along with it. So IMO, it's pretty darned important to at least try to get the distribution even. And the factory intakes are **** poor at that job.
Ideally you'd want a "wet flow" single plane carb style intake for distribution. And to spray a mega ton of straight meth in the turbo inlets. If enough volume was sprayed, you could achieve an intercooler like effect, up the turbo efficiency, and a large octane boost. It would also be finicky to tune and a fire hazard. But it has been done with great success.
Now I'm not saying it won't "work" With a factory intake. That's how I ran it as well. Just have to realize the limitations and read the plugs. Also helped that I had an ECU that could add or subtract fuel to cylinders individually.
Typical volume kits do most of their work in the cylinder, pulling heat and slowing the flame front down to help prevent detonation. This is why you see little to no performance gain w/ typical W/M alone. It's very similar to running higher octane fuel. Dumping some 110 in your tank isn't going to do squat for ya performance wise if you don't up the boost/timing to go along with it. So IMO, it's pretty darned important to at least try to get the distribution even. And the factory intakes are **** poor at that job.
Ideally you'd want a "wet flow" single plane carb style intake for distribution. And to spray a mega ton of straight meth in the turbo inlets. If enough volume was sprayed, you could achieve an intercooler like effect, up the turbo efficiency, and a large octane boost. It would also be finicky to tune and a fire hazard. But it has been done with great success.
Now I'm not saying it won't "work" With a factory intake. That's how I ran it as well. Just have to realize the limitations and read the plugs. Also helped that I had an ECU that could add or subtract fuel to cylinders individually.
How much difference as far as reported Temp? I really don't know. I'm sure it would vary wildly. The amount of fluid and air flowing in the pipe would have a huge effect.
As far as it's actual affect on overall temps between those 2 locations? I'd say diddly. As mentioned typical small volumes do 98% of the work in the cylinder. Only real benefit in location swaps IMO is if you spray pre turbo... Or if maybe you had a remote setup with a massive length of piping. Spraying post IC or at the TB I don't' think would make any noticeable difference.
As far as it's actual affect on overall temps between those 2 locations? I'd say diddly. As mentioned typical small volumes do 98% of the work in the cylinder. Only real benefit in location swaps IMO is if you spray pre turbo... Or if maybe you had a remote setup with a massive length of piping. Spraying post IC or at the TB I don't' think would make any noticeable difference.