Quote:
Originally Posted by vutall
Excellent build thread, reminds me a ton of when I have my EVO X SE.
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Thanks!
Quote:
Originally Posted by vutall
I have a question for you however. I read through this whole thread and when the comments go to FI startd coming in, I found your answers quite robust and well thought out. There was something that was never mentioned though and I haven't quite figured it out. It's something I see many people in the auto world "forget" exists.
If a turbo generates too much heat, and a SC has too many replacement consumables (plus a bit of heat generation)...
Why not water meth injection? You could see some very significant gains and when done correctly, it runs much cooler.
I'm not sure on how well it plays with E-85 however...
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Specifically for a track application, depending on the kit design and presence of supplemental cooling modifications, yes, a turbo FA20 can heat soak to the point of noticeable performance degradation and risking the motor. This is most prominent in the front mount turbo kits where a big radiator, vented hood, and lots of heat wrap are needed to control it. The same can be true for twin screw SC's and helical gear-driven centrifugal SC's if you push them hard enough on a track. There is an excellent thread on combating the heat here in the FI subforum:
http://www.ft86club.com/forums/showthread.php?t=53580
I'm not sure what you mean when you said SC's have too many replacement consumables, though. The only consumables on a SC I'm aware of are gear oil/traction fluid and the drive belt; both of which are supposed to be consumed in tens of thousands of mile long intervals.
I think that Rotrex SC's are an exceptional option because they have proven to be the best at handling the heat from track abuse. @
CSG Mike has measured intake air temperatures lower than stock in SoCal on a Jackson Racing kit. Heat is not an issue on track either, thanks to the Rotrex internal traction drive system which transmits power through friction forces between its rolling elements. The traction fluid momentarily increases viscosity under high surface pressure, enhancing the traction drive performance by securing the optimum friction between rolling elements while cooling and protecting the system. With this you get excellent transient response and the ability to spin the impeller pretty fast- nearly as fast as some turbochargers, and characterized by high adiabatic efficiency and low noise.
[ame]http://youtu.be/eQDbk8CJya0[/ame]
The kit keeps the traction fluid cool with a cooler and reservoir which the SC naturally pumps through it.
What I'm getting at is that with a Rotrex SC specifically, there is no need for WMI when you can just run E85 and get gains through tuning, while also cooling the combustion temperatures and resisting detonation by nature of burning 105 octane ethanol. The intake air temperatures still stay low because the compressor is efficient and the intercooler is able to do its job in all climates and applications. WMI would just be an unnecessary complexity IMO since you'd have to put in a tank, lines, port adapter, and spray/trigger mechanism and tie all that in seamlessly.
Think of it as a crutch rather than a true solution to the problem. I've seen WMI setups on twin screws that were deemed necessary because the twin screws heat soak like a mofo on track in warm climates and the goal is to use the water's cooling and octane of the methanol to provide power consistency and prevent detonation due to high cylinder temps. E85 does essentially the same thing on its own and paired up with a SC that doesn't overheat in the first place...
