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Author Topic:   Trying to cool running on gas.
poboy2
Dirt Maniac

Total posts: 199
posted September 09, 2002 07:02 PM
Actually running in a LLM class. But I know alot of B-mods have to run on gas also. How do you keep engines cool running the smaller radiators? I heard that there were some gas additives that may help. We are running 377 and 406 engines. Any suggestions?

modi25
Dirt Newbie

Total posts: 2
posted September 09, 2002 07:57 PM
first you need to have a good 2 row aluminum radiator, not the lightweight single row. build a good tight fitting shroud that fits well around radiator and fits around fan. make the part around the fan about 1 to 1 1/2inches bigger than the diameter of the fan and space the fan where it is half in and half out of the shroud. in front of the radiator you will need a good screen to keep mud out of it and if your nose extends very low to the ground you might have to cut some holes in it for extra cooling but i would run it first before i cut the holes bcause you may not need them. also weekly maintenance of radiator will be required to cleen the fins out.

Dustejr73
Dirt Full Roller

Total posts: 29
posted September 09, 2002 08:43 PM
you can also talk to your engine builder about drilling a hole on each side of the block between the center cylinders about 1 inch from the heads. you run hoses from these holes to the sides of the water pump. i have this done on my 406 and it helps cool the center cylinders. also having a good 2 row radiator such as a Griffin is a must.

Mod-man
Dirt Newbie

Total posts: 1
posted September 09, 2002 09:05 PM
If you are having heating problems and have changed everything that could be a problem externally, and no difference. The next palce to look is internally. You probably will need to rehone the block to get the right cross-hatching in the cylinders. Had a 406 once that I could not keep cool. Pulled it apart, took it to the mmachine shop, I think the used a 280 stone on it, put it back together with new rings, and problem solved.

outlawstock17
Dirt Maniac

Total posts: 163
posted September 09, 2002 09:28 PM
evans cooling offers a waterless coolant that is advertised to run cooler. you can't have any water in the system though. an engine oil cooler will also help and is an area usually overlooked by most grass roots racers. also, most aftermarket aluminum radiators aren't very efficient. two 1" cores don't cool as well as four 1/2" cores. also, look for a radiator with more fins per inch. more surface area makes the radiator more efficient. it's not necessarily how much water it holds, it's how much surface area it has.

cut_n_up
Dirt Roller

Total posts: 20
posted September 09, 2002 09:31 PM
what do u have where the thermostat goes any restrictors?

Tom Asmus
Dirt Maniac

Total posts: 161
posted September 09, 2002 09:51 PM
I run a a Ford in my modified, and its on gas. I have no problems with my car overheating, I run no thermostat and no restrictor. The key to ours runnin cool is we have a Stewart water pump, that keeps the car runnin 160 to 190 on 100 degree nights out here in Wyoming!

George Gilliland
Dirt Full Roller

Total posts: 39
posted September 10, 2002 11:09 AM
When I first ran a modified I ran on gas. Two core aluminum radiator, 160 deg. thermostat, and the pulleys ran the water pump slightly faster than the engine. I had to wash the radiator every week. The temperature never went higher than 210. I have a good shroud and it would cool down a little on yellows. With the limited space for a radiator there is not a lot of safety margine there.

Mod57
Dirt Full Roller

Total posts: 32
posted September 10, 2002 08:11 PM
This sight has allot of real good info on this subject, definatly worth reading.
http://www.grapeaperacing.com/GrapeApeRacing/tech/coolingmods.cfm

Dirt2race
Dirt Full Roller

Total posts: 40
posted September 11, 2002 11:16 PM
Poboy, I have ran gas for 3 years in a mod with no shroud and no openings in the nose. Stewart water pump, the good reduction pulleys, the good green stripe water hoses, 2 bottles of Red Line water wetter, and 3/4" restricter. I have ran 350's, 383's and 406's ranging from 380 to 500 HP, with absolutley no problem. I believe the key is to NOT get to radical with the timing and use the good water pump and hoses and also use the old 4 blade Ford fan. I have never had an engine go over 200 deg. I also use a 27" 2 core AFCO radiator. All of these pieces are 3 years old. I take a lot of time to keep the radiator straight and clean. Again I do not run a shroud. Its not that I don't believe in a shroud, I just have not needed one. On cool nights, it is hard to get the motor up to temp, so I advance the timing from 35 to 37 deg. That is usually good for about 10 deg in temp. Good Luck.

Gene
Dirt Maniac

Total posts: 183
posted September 17, 2002 06:02 PM
THANK YOU MOD57!!!!!

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