Temp Control for an open road race - ZR-1 Net Registry Forums

LancePearson · 06-26-2013

I keep thinking about the remote possibility I might try an run the Texas Big Bend Open road race which is time trial based 55 miles in one direction then in speed class when all have finished, running it back the other way.

As it's Texas and running in a 120-140 mph class would have the car humming right along, what preparations do you think would be necessary to keep the engine temperature in the right range? If entered at the 130 mph class that's about 25 minutes each way with some time between directions and runs so is a sustained run a 130 mph probably in fifth gear I would imagine with a 3:45 rear end. A different thing than 15 or 20 second runs...

Any experience?

I did not run the Chicago 1/2's in early June but yesterday on my little semi private 2.3 mile stretch of isolated, flat, no cross roads or driveways country straight road locally pushed the car quickly from a rolling 10 mph to 145 mph then let it unwind down, drove all the way to the area I turn around in a quick mart then ran it 120 on the way back. It was 94 degrees F. out and the thermostat stayed right where it usually does at the 180 mark which was surprising as I pushed the car through the gears to about 7,000 rpms before shifting in each case. Pleasantly surprised, I might add.

I am getting used to the speed but at 140+ needed to shift into fifth and decided to keep both hands on the wheel and just let it top out and then unwind so I could glance at the gauges, etc.

The trees go by pretty fast as you know.

Anyway, any cooling system advice for something like the Big Bend Open with the car?

Lance

Tyler Townsley · 06-26-2013

If you have a stock system and run rpms above 5800 you have no water going through the radiator over that rpm, there is a lot of discussion on this in the archives, just search using my name.

Tyler Townsley

PhillipsLT5 · 06-26-2013

as Tyler said, keep RPM under 6K for any extended period of time

tf95ZR1 · 06-27-2013

Remember, the idea was that at high RPM's the
high pressure would blow the radiator. Would the
1/8" holes drilled through the perimeter of the
thermostat talked about years ago help?

Hey Phillip; 1,000 posts! Congrats!

06-26-2013	#1
LancePearson Join Date: Dec 2012 Location: Chester, Virginia Posts: 457	Temp Control for an open road race I keep thinking about the remote possibility I might try an run the Texas Big Bend Open road race which is time trial based 55 miles in one direction then in speed class when all have finished, running it back the other way. As it's Texas and running in a 120-140 mph class would have the car humming right along, what preparations do you think would be necessary to keep the engine temperature in the right range? If entered at the 130 mph class that's about 25 minutes each way with some time between directions and runs so is a sustained run a 130 mph probably in fifth gear I would imagine with a 3:45 rear end. A different thing than 15 or 20 second runs... Any experience? I did not run the Chicago 1/2's in early June but yesterday on my little semi private 2.3 mile stretch of isolated, flat, no cross roads or driveways country straight road locally pushed the car quickly from a rolling 10 mph to 145 mph then let it unwind down, drove all the way to the area I turn around in a quick mart then ran it 120 on the way back. It was 94 degrees F. out and the thermostat stayed right where it usually does at the 180 mark which was surprising as I pushed the car through the gears to about 7,000 rpms before shifting in each case. Pleasantly surprised, I might add. I am getting used to the speed but at 140+ needed to shift into fifth and decided to keep both hands on the wheel and just let it top out and then unwind so I could glance at the gauges, etc. The trees go by pretty fast as you know. Anyway, any cooling system advice for something like the Big Bend Open with the car? Lance __________________ Lance Pearson Chester, Virginia [COLOR=red][I]'76 L48 four speed[/I][/COLOR] [COLOR=red][I]'91 ZR-1 #00682[/I][/COLOR] Net Registry #1461 Last edited by LancePearson; 06-26-2013 at 10:12 PM.

06-26-2013	#2
Tyler Townsley Join Date: May 2005 Location: Nichols, FL Posts: 615	Re: Temp Control for an open road race If you have a stock system and run rpms above 5800 you have no water going through the radiator over that rpm, there is a lot of discussion on this in the archives, just search using my name. Tyler Townsley __________________ 55 Polo White (Project) 61 Jewel Blue (Sold to buy above) 66 Nassau Blue 68 Torch Red 88 ZR1 Blue 90 ZR1 White

06-26-2013	#3
PhillipsLT5 Join Date: Aug 2005 Location: Scottsdale, AZ Posts: 2,452	Re: Temp Control for an open road race as Tyler said, keep RPM under 6K for any extended period of time

06-27-2013	#4
tf95ZR1 Join Date: Aug 2005 Location: Northridge, CA Posts: 1,461	Re: Temp Control for an open road race Remember, the idea was that at high RPM's the high pressure would blow the radiator. Would the 1/8" holes drilled through the perimeter of the thermostat talked about years ago help? Hey Phillip; 1,000 posts! Congrats! Last edited by tf95ZR1; 06-27-2013 at 03:11 AM. Reason: Wanted 2