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Howard Jones · 02-19-08, 11:34 PM

Dean, I don't believe that you can run this car without fans on the street or for that matter at speeds less than 40MPH unless it is really cold outside. One of the tricks is to "bank" cooled water when you can. What I mean is when you anticipate a need for cooling such as a traffic light ahead you can switch on the fans and begin the cooling before you come to a stop. The worse thing you can do is sit there and get hot and then put on the fans. No fans, no cool water.

On the track, waiting on the grid with the engine at idle will heat up the coolant and when you need the extra cooling it will have been used up on the pit lane. Especially when the car has been really run hard and everything is good and hot after a session. On a hot day it will take a good hour to really cool things down in the pits. If you go back out with water/oil temps all the way up and sit in the pit lane for ten Min's waiting to go out without fans I think things won't work out very well. Maybe on a 50F day you can get away with it but forget it when it's 90F. Fans are your friends.

As far as performance goes. I don't believe that you can really get much down-force on the front without keeping the air out from underneath the car. I've tried just about everything that can be done on TOP of the car to gain down-force but unless you use a real wing on the rear, keep the air out from under the sills along the side and a splitter on the front as part as a big ugly air dam then these cars are not going to produce down-force. In fact it would be quite an achievement to reduce lift to zero. The main thing when on the track is to keep the front ride height about a inch lower than the rear and as low as it will go in the front without screwing up the front geometry.

The good news is at most tracks top speeds will be under 160MPH and then for only for a few seconds. My car feels pretty good and stable approaching these speeds so I have been concentrating on mechanical grip more than aero. Besides I love the look of these cars too much to change mine much beyond what was done to them in their day.

So put in the fans and you won't be sorry. There is nothing worse that a overheating problem in an otherwise nice hotrod to ruin your day.

02-19-08, 11:34 PM	#6 (permalink)
Howard Jones 10 tenths Join Date: Jun 2002 GT40: San Francisco Bay Area California USA Posts: 1,862 Rep Power: 25	Re: Rad. fans and air flow Dean, I don't believe that you can run this car without fans on the street or for that matter at speeds less than 40MPH unless it is really cold outside. One of the tricks is to "bank" cooled water when you can. What I mean is when you anticipate a need for cooling such as a traffic light ahead you can switch on the fans and begin the cooling before you come to a stop. The worse thing you can do is sit there and get hot and then put on the fans. No fans, no cool water. On the track, waiting on the grid with the engine at idle will heat up the coolant and when you need the extra cooling it will have been used up on the pit lane. Especially when the car has been really run hard and everything is good and hot after a session. On a hot day it will take a good hour to really cool things down in the pits. If you go back out with water/oil temps all the way up and sit in the pit lane for ten Min's waiting to go out without fans I think things won't work out very well. Maybe on a 50F day you can get away with it but forget it when it's 90F. Fans are your friends. As far as performance goes. I don't believe that you can really get much down-force on the front without keeping the air out from underneath the car. I've tried just about everything that can be done on TOP of the car to gain down-force but unless you use a real wing on the rear, keep the air out from under the sills along the side and a splitter on the front as part as a big ugly air dam then these cars are not going to produce down-force. In fact it would be quite an achievement to reduce lift to zero. The main thing when on the track is to keep the front ride height about a inch lower than the rear and as low as it will go in the front without screwing up the front geometry. The good news is at most tracks top speeds will be under 160MPH and then for only for a few seconds. My car feels pretty good and stable approaching these speeds so I have been concentrating on mechanical grip more than aero. Besides I love the look of these cars too much to change mine much beyond what was done to them in their day. So put in the fans and you won't be sorry. There is nothing worse that a overheating problem in an otherwise nice hotrod to ruin your day.