[94bird]

Are the fans in series in our LT1 engines? Can I remove one of them and still have one working fan? I'm in the middle of doing a few things on the car and the engine isn't running so I'm hoping someone knows before I reinstall everything.

[Jon A]

Interesting, guys. I didn't know they made the switch that early.

I hope you can find some info on those flow rates, Mike. They would be good to know.

I'm not sure how needed the fans are on the track--that's why I'm experimenting. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/wink.gif) One would think that once you're over 35 MPH or so the fans wouldn't be doing much. But in the past I've been in "rolling traffic jams" traveling in the 30-50 MPH range in hot weather and the car will get hot without the fans programmed to come on soon. On one such day I saw temps over 215--with the fans on low speed. This makes me think these cars might depend on them a bit more than you'd think. It could be the way the air is taken in just isn't all that efficient--being scooped off the ground, redirected upward, then it needs to turn again to go down through the radiator....

When studying some fan tech I found many interesting things (Google is cool). A system like this would likely be classified as a "high resistance" system, especially with the condenser in front of the radiator. Here's what that means: In a system with low or even figure zero resistance, two fans in series won't flow any more than one fan. One could consider the atmosphere as the first fan. If you remove the radiator and the speed at which the free airflow matches the CFM of the fan then the fan isn't helping you at all. But put a big resistor in there and this is where fans in a series can flow a lot more than one fan alone--or the atmosphere and the fans work together to flow more air than either would alone. This is why you see "pusher" and "puller" fans working together in some applications. The radiator obviously causes a pressure buildup in front of it as it slows down the air. When this happens less air is going to want to go into the radiator opening so maybe figuring that vs vehicle speed isn't an accurate way to come up with a CFM figure--that assumes the radiator has zero resistance to flow.

Who knows. One thing to consider as we all think of tracks as such high speed driving, I consider PR a pretty "high speed track" but my average speed is only 80 MPH there. There are tons of tighter tracks where I'd average slower. So there is quite a bit of time spent at speeds that aren't all that high.

But like I said, I'm still experimenting. One of these track days I'll try to just shut off my fans completely and see what happens.