Reflections of my 1st real drive in the GTR

[San Diego GTR]

I had 60 miles on the car with all short drives of a few miles a piece. But today we went 140 miles in 80 degree weather. No AC and the side windows aren't yet mounted. It was hot but the car performed fantastically. What a car! The LS7;G50/52 combo is amazing, although I might want a higher 5th someday. It runs at 3k rpm at 80 mph. Some tweaking still to do to cut down on some of the body noises and rattles but it sounds pretty tight all in all. The LS7 sounds like a diesel locomotive back there pushing like, well, a freight train.

One observation that I wish I would have done early in the build. My front roll bar and aluminum in the cockpit get so hot that you can't touch them for very long without it getting too hot. I wish I would have done a better job insulating the radiator tubes and heater tubes running up and down each side of the car. I'm considering cutting the bottom of the side pods the length of the car just to get at the heater tubes and do it the right way. I don't remember ever reading this on the build manual or on this forum. Maybe I missed it. This is really the only thing at this point that is a problem. Otherwise, the car is a beast.

Paul

[Davrianman]

Congrats Paul!

Sounds like you have made a monster! Will hopefully have mine on the road this year... Can't wait for that first drive.. :-)

I spent quite some time insulating the side pods and side panels. I also put the heater pipes below the luggage pod and insulated them. I think it is quite a common problem. I have even added air vents into the luggage pods from the aircon... Don't think they will do a lot, but hoping they may keep my beer cool on the way to LeMans...

Not sure what you could do with yours now to help though, other than taking off the body :-(

Perhaps carpet the sides to keep the heat away from your legs?

Happy motoring,
Martin

[Pb3]

I believe the factory specifically advised against insulating all the radiator and heater pipework, as it helps with heat rejection, all be it in the wrong place. That statement was true some years back and I chose to ignore it as have many since and insulated all the pipes with that fibreglass/foil pipe lining material stuff. I am probably glad I did too, I have no AC, but don't suffer greatly when the weather heats up.

[crafty]

If the Ultima cooling system really needed the pipes unlagged in order to work, then the radiator is too small. I have my pipes lagged and no probs at all.

[CanAm Dave]

I have both cooling pipes running down the drivers side(Due to my supercharger installation)! They are not insulated and I don't have any issues with heat! But I do run an electric water pump and have an uprated radiator and fans! I guess it's not so much of an issue with our crap weather!

Regards Dave

PS Glad your enjoying the car!

[k wright]

I have a black GTR without A/C and it is comfortable in hot weather as long as you’re moving (40 mph or faster) and the side windows are out. I covered the pipes with header wrap and filled the area between the inner and outer passenger compartment panels with Cool It aluminized fiberglass mat. The “outer” surface of the outer skin is also covered in the mat with the alloy coating facing the pipe. In addition the luggage bins are covered in the same mat.
The route of the pipes seems to offer little in the way of real cooling and I felt that it wasn’t the best plan to allow all of this heat into the car and force the installation of an A/C unit. The weight of the insulation is at worst 10 pounds and it never needs servicing.
I have never had a problem with engine overheating despite several track days in 100 degree heat.
If you look on the USA website you can see details in my gallery on how my windows have been made easily removable. When they are out they are stored in a nylon pouch behind the passenger seat. I would highly recommend that you make this modification to your windows as well. Now that your car is assembled you may consider drilling some small holes in the interior panels to allow pouring some insulating foam in them. I don’t have experience with this foam but you should be able to find someone here that does.

Ken Wright

[San Diego GTR]

k wright said:

I have a black GTR without A/C and it is comfortable in hot weather as long as you’re moving (40 mph or faster) and the side windows are out. I covered the pipes with header wrap and filled the area between the inner and outer passenger compartment panels with Cool It aluminized fiberglass mat. The “outer” surface of the outer skin is also covered in the mat with the alloy coating facing the pipe. In addition the luggage bins are covered in the same mat.
The route of the pipes seems to offer little in the way of real cooling and I felt that it wasn’t the best plan to allow all of this heat into the car and force the installation of an A/C unit. The weight of the insulation is at worst 10 pounds and it never needs servicing.
I have never had a problem with engine overheating despite several track days in 100 degree heat.
If you look on the USA website you can see details in my gallery on how my windows have been made easily removable. When they are out they are stored in a nylon pouch behind the passenger seat. I would highly recommend that you make this modification to your windows as well. Now that your car is assembled you may consider drilling some small holes in the interior panels to allow pouring some insulating foam in them. I don’t have experience with this foam but you should be able to find someone here that does.

Ken Wright

Ken,
Thank you for the suggestions. It sounds like you did a really good job of solving this problem. I will also be doing the quick release window option.

I currently have a very sophisticated marine grade insulation material mounted to the back side of the aluminum panels around the floor and sides of the cab. It is about an inch of foam and has a silver finish on the heat side which should reflect heat pretty well. It is like Dynamat with foam in the middle. What I forgot to attend to was the black steel frame members. I didn't cover them with anything and they get direct radiated heat from the radiator tubes. Do you think if I filled the void where the tubes run under the luggage compartments with a construction insulation expanding foam that that would work? I think I'm going to try it and see how it works. I'm hopeful that it will. I am going to slip header wrap material in between the tube and the most obvious areas where the radiator tube is up against or very close to the frame tubes.

Thanks,
Paul

[k wright]

Sounds like it would work well. You may be able to get a significant amount of your pipes covered by accessing the area behind the alloy panel in the front fenderwell.

ken