Do big blocks run hot?
Thread Starter
7th Gear
Joined: Jul 2004
Posts: 7
Likes: 0
Do big blocks run hot?
i have a 69 427 where my feet get pretty warm on hot days, is it true that big block engines run hot and by "sitting" on the engine it is hard to keep the heat away from your feet?
Team Owner
Joined: Feb 1999
Posts: 34,453
Likes: 665
From: Republic of Texas
If it's running hot then you have a problem somewhere. I'd evaluate the thermostat making sure it's opening, then I'd check the radiator. Normally if the water pump is going out it will leak and/or make noise. A fully fucntioning coolant system will properly cool a BB. 
Team Owner
Joined: Feb 1999
Posts: 34,453
Likes: 665
From: Republic of Texas
Originally Posted by cruiser69
Sorry, I didn't explain very well. What i meant was the heat that comes off off the engine makes the interior very warm. The engine temp is fine i just cant keep the interior cool enough on a hot day
Then yes, the heat from the floorboard is normal. This is why many guys switchto side exhaust, it eliminates the problem. I believe some herr have wrapped their exhaust/headers to reduce the heat.
Last edited by Corey_68; Oct 4, 2004 at 01:11 PM.
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
there is a whole series of steps to take which can significantly improve your in-cabin comfort. The steps are documented several places, including the "weekend projects" book. Off the top of my (flat) head, I checked the firewall for holes (usually missing grommets) that allow heat into cabin. Install a heaterhose cutoff valve so hot air is not circulating thru your heatercore during the summer. This would give you hot air out the vents even if the heater and fan are turned off. Check the shifter boot (if 4spd) for tears and replace. There is an inner rubber boot underneat the outside one. Check underneath for addition or possible replacement of foam collar around trans and aluminum foil backed heat shield around trans. You could install heat shields between the exhaust pipes and the floor. I put in insulation (heat shield type stuff) up against the firewall. Finally you might want to rip out all of your carpet and install foil backed insulation underneath your new carpet.
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
Originally Posted by cruiser69
thanks, you settled a bet for me!
what bet was that? You are driving a 35 year old car. It is very common with cosmetic restorations that make the car look very nice but leave out invisible items like under-car heat shields or even undercarpet insulation. You will have to survey original owners to find out how hot they were inside when new. 
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Safety Car
Joined: Nov 2001
Posts: 3,728
Likes: 1
From: Maple
Originally Posted by Corey_68
Then yes, the heat from the floorboard is normal. This is why many guys switchto side exhaust, it eliminates the problem. I believe some herr have wrapped their exhaust/headers to reduce the heat.
Racer
Joined: Jul 2004
Posts: 352
Likes: 1
From: Minneapolis Minnesota
I have insulation and the heatshields and it gets warm with the headers.
I did not know that Vipers heat up. I've never been in one.
One more note, I saw a C6 Sunday and at first glance I thought it was a Viper.
-Dan
I did not know that Vipers heat up. I've never been in one.
One more note, I saw a C6 Sunday and at first glance I thought it was a Viper.
-Dan
Melting Slicks
Joined: Oct 2000
Posts: 3,023
Likes: 2
From: TEXASTEXASTEXASTEXAS TEXASTEXASTEXASTEXAS
St. Jude Contributor
Originally Posted by Larry B.
All of my seals and insulation are in place. the heater?AC doors work fine and heat is not a problem in my BB69 even with the A/C on.
JB
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
I believe in header wrap. My headers have been wrapped for over 10 years without a problem. There is no problem with hot floors and when you lift the hood after hard driving there is no wave of heat that strikes you.
