[Nezil]

Originally Posted by ZM2

WMI ($1.5k upfront, $500/yr)
HP Gain: 5-10hp. I wouldn't tune for WMI and I'm already using E30 to keep power levels up on summer days, so modest hp gain.
Pros: Lower IATs give a little power bump and helps prevent or buy time from heat soak. Helps with HPFP crashing under WOT at high RPMs.
Cons: Running costs & transporting jugs of 50/50 meth/water. I'd need to go with at least 750cc to keep IATs down with higher power levels, so if I'm at an open track day that's likely 8-10gal of mix I'd need to bring with me.

This probably is true... though 50/50 meth/water isn't that dangerous, probably even less of a combustion risk than regular gasoline.

I'm not running 750cc myself, but I am running the system all the time in my daily driver. The WMI system I'm using only injects when the injector duty cycle is greater than 50%, and progressive after that. Under light throttle it doesn't inject
at all, and on a 20 minute commute to work in traffic I may see 3 or 4 seconds of 'On' time. The 1 gallon windshield washer reservoir lasts just over 2 tanks of daily driving use, but would certainly be drained pretty quick on track.

I'm also not sure you'd spent $500 / year on meth, but that depends on your track usage I guess. I think I paid $30 for 5 gallons of meth, and that makes about 12 gallons of 50:50 (because it's mixed by weight not volume). That's 24 tanks of gas daily driving, or about 4,800 miles. I do less than 10,000miles / year, so for me, it's less than $100 / year in meth.

Also, not a pro or con, but an observation: WMI wouldn't help with HPFP crashing when you're just cruising around and then punch it from mid RPMs in lower gears. The additional WMI fueling doesn't happen quickly enough to keep the HPFP from crashing in those situations, but when rocking down the straightaway in higher RPMs/gears WMI should help with HPFP crashing.

I'm not convinced that this is the case... It surely depends on the WMI system you choose to install. If you're relying on a pump in the trunk with many feet between the pump and the jets then you may very well be correct, but with a system that maintains constant pressure controlled by a solenoid just inches from the jets that may not be the case at all.