Yes, the radiator fan is powered by a hydraulic fan that runs off of the power steering pump. It provides higher fan performance and low engine speeds. It was a system developed by ITW just before Valeo bought them out. It is a decent system that DCX is using on several vehicles, however it approx $80 more expensive then a conventional electric fan system.
Exactly. I removed mine and put in a dual electric fan setup. Less parasitic loss.
How do you figure? It's not an engine driven fan, it's hydraulically driven. And it runs off the power steering pump which I assume you are still using. And although it maybe less load on the PS pump, I can't imagine a fan would have been a huge load anyway. Nowhere near the load of the steering rack.
Shit, if you wanted to reduce parasitic load on the motor, my guess would be you would have to remove the a/c, PS pump, and use an electric water pump (leaving only the alternator) to see any noticeable gain on the dyno. Even then I don't think it would be worth it on a street car.
Well -to be honest parasitic loss is secondary but real none the less and I'm trying to break 1,200 hp. Remember what turns the pump...The main improvement is a MUCH MUCH higher CFM rating as I need to pull air through an intercooler and transcooler - overkill - maybe - but I'm doing my best to build it right. It also has the benefit of being able to have both a therostatically controlled turn on and a manual one...thats a little hard with the hydro fan...
Well -to be honest parasitic loss is secondary but real none the less and I'm trying to break 1,200 hp. Remember what turns the pump...The main improvement is a MUCH MUCH higher CFM rating as I need to pull air through an intercooler and transcooler - overkill - maybe - but I'm doing my best to build it right. It also has the benefit of being able to have both a therostatically controlled turn on and a manual one...thats a little hard with the hydro fan...
Wormsterr-
Are you the one who did the all black Paxton s/c motor recently? I asked in another thread---maybe you didn't see it---but why didn't you go to a big air/air intercooler instead of that little air/water one?
Sorry must have missed it. I'm actually just in the middle of the build right now - assembing parts etc. Hoping the motor will be done in a couple weeks so we can start assembling and testing. I tossed the stock intercooler and have a larger air/water intercooler. After testing we'll see where we stand as far as the temp of the charge and boost levels. I'm still learing every day.
Actually the hydraulic fan motor will out perform 12v electric motors. I was involved with the design of the SRT10 cooling system. Electric fans were considered, but the hydraulic system out performed the electric fans. Unless you are going to upgrade your alternator to 300+ amp unit with a tiny pulley to keep the rpms up a low engine speeds. Please post your results, I would be interested in seeing how the electric setup works. BTW, you can turn the stock fan on thermostatically and "manually", it operates off of a solenoid.
Quote:
Originally Posted by womsterr
Well -to be honest parasitic loss is secondary but real none the less and I'm trying to break 1,200 hp. Remember what turns the pump...The main improvement is a MUCH MUCH higher CFM rating as I need to pull air through an intercooler and transcooler - overkill - maybe - but I'm doing my best to build it right. It also has the benefit of being able to have both a therostatically controlled turn on and a manual one...thats a little hard with the hydro fan...
I was talking to Dan Cragin yesterday. He said a few of the track guys had replaced the hydraulic system with electric fans, but went back to the hydraulic system citing an inability to keep the temps down with the electrics. Dan said the hydraulic system is very efficient.
lol... how many times have I posted on the Morgue about how efficient the Hydraulic system is? and I was an OPPONENT to it when I first heard about it.
The Hydrualic motor, besides having almost 100 speeds and ramping ability creates MASSIVE torque compared to a comparably sized electric motor. this allows a very aggressive fan blade pitch to be used, and it moves some serious CFM's. I have yet to hear of any SRT with a Hydro system that has cooling issues.
It takes power to run a fan motor- any kind. Period. Whether you run it off the PS or the electrical system, it will come back as a loss. an electric fan loads the alternator, just as Womsterr concluded that the the Hydro fan loads the PS system. What he forgot is that a PS pump is ALWAYS sapping power, whether it is driving anything else or not! The Hydro fan just takes advantage of that "already lost" power. By adding electric fans, it now has a dual burden, both the original PS losses, as well as the Alternator now to cycle the spal fans.
Just for kicks, if you want to see how serious of a system the SRT cooling system is, pop off the thermostat sensor plug when the engine is idling on an SRT. The PCM will ramp the fan QUICKLY to 100% safety mode...and be prepared for a small hurricane.
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