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I have the basic Snow Performance water/meth kit installed in my car. When I got the kit, it came with a large nozzle, and VERY large nozzle. I installed the smaller of the two, which was Snow Performance's Size 4 Nozzle, appropriate for 400hp cars... The IAT's were great! (100F in boost and steadily decreasing when the WMI pump is running.) But the engine did not seem to like the large volume of water/meth. I ran with it for about a week while as I waited for the Size 2 nozzle to come in the mail. Engine likes the new nozzle and my current IAT's in boost hit a maximum of 120F when it's hot out. If the weather is cool outside, IAT's are around 100F. If the water/meth in the tank is also at a cool temp, I noticed it had a substantial effect on IAT's. Anyone ever throw ice cubes in their meth tank? lol
There are a couple of calculators out there to help you pick an appropriate nozzle for your WM setup but it sounds like you got a better nozzle for your car. If you want to fine tune the system while keeping your nozzle you should be able to adjust the pressure on the pump to help increase/decrease the amount of wm you are spraying.
Since your nozzle is pre blower you might want to look into adding a second small nozzle in your charge piping post blower. Also I am not sure if your blower has teflon seals but since you are injecting pre blower it will most likely destroy them.
I have a VW GTI and have been playing with WM for ~10 years and have tried all kinds of different setups with varying results. Granted my testing has been with a turbo car using a progressive controller so my experiences are slightly different.
I would not suggest you put ice in your reservoir but instead change the ratio of your w/m mixture. Also ALWAYS make sure you use distilled water. I would also suggest you keep an extra jug of w/m (make sure the lid seals TIGHT and is in a container that can hold methanol) in your car in case you run out of juice while you are driving around.
Sorry for spamming, but I got hooked and went through the sim again updating a load of efficiencies, port sizes, cam profiles etc for your setup with the 1.6l engine.
When I incorporated these changes into the model it reproduced your virtual dyno information very closely. This is at 1.35 pulley ratio, 90kPa atmosphere with an intake pressure drop of 4kPa by 7krpm (a decent intake setup).
Boost levels (absolute) stayed around 0.35 to 0.4bar. Peak torque was moved earlier and slightly increased to 121.7lbft @4krpm, torque at 7krpm was identical to your vd testing at 103lbft. With the smaller ports and cams now in the sim it caused it to replicate your power curve very closely, reducing top end power. Sim says 137whp @ 7krpm. If you notice in your VD graph hp and tq do not calculate correctly. It says 124whp / 103lbft, but 103lbft @ 7krpm is (103*7000)/5252= 137whp, not 124whp. I think this is a quirk of how VD smooths the lines, I think it does them separately rather than smoothing torque then calculating power from that or vice versa.
Long story short, I don't think your power figures are unexpected any more. Move to the seaside or put a smaller pulley on it
Sorry I haven't checked this thread in a little while, but holy crap dude! That's seriously impressive you found out pretty much exactly the answers I was looking for. I'm confident everything you came up with is pretty accurate. That's a real neat simulator you got! I'm glad to find out I'm not actually missing power and that my setup is producing the figures it should be. Also, good job pointing out the quirky VD calculations. Before I saw your sims, I was working on revising the intake pre-charger as a result of everyone mentioning it was restrictive. I ended up removing the 90 bend, installed a velocity stack bell mouth, and removed the air filter temporarily for the test. I did a few pulls with the revised intake setup and I found there was no difference to the torque curve at all. Although, there was a very slight increase in torque (+3lbft) at the top end. With those results, I can conclude the original intake was not that restrictive.
I wonder how much of a gain I would see if the engine were at sea level. I did order a smaller supercharger pulley which is still making its way through the mail. I will post an update when I get it. Also, I have found that boost is slightly higher (+1psi) when WMI is active. Injecting pre-charger seems to help produce a better airtight seal between the rotor lobes and the housing.
No problem mate, was interesting to see what the sim came up with. I think somewhere on this thread you said you had ordered a 76mm pulley? So pulley ratio of 1.71?
This is what the sim says comparing your 1.35ratio to 1.71 @ 0.9atm
1.71ratio tops out at 123Kw or 165whp. PR moves to about 1.9, air temps to 145degC.
If you lived at see level this is what I reckon your engine would produce:
About another 17Kw / 23whp by 7krpm. The two traces are 1.35 and 1.71pulley ratios again.
I'd be very interested to see your results when the pulley arrives, and how close the sim is!
Thanks for the info on the WI boost pressure, that aligns to what I have read, that overall there isn't a massive change in charge density when using it for air cooling. My engine doesn't lend itself to working that out, I spray most of my water straight into the cylinders from just behind the injectors without much time for air cooling.
3lbft doesn't sound much, but at 7krpm that is 4hp or 3% output. Also when you put your smaller pulley on that restriction will increase because more air is trying to move through the system, so may be worth looking again when you get a chance / motivation to do so. My sim didn't take into account any small proportional increase in intake restriction from flowing more air through it.
02-09-2022, 05:22 PM
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