Anyone recommend a very effective anti-heat soak spacer?

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1970dartcustom

1970dartcustom

of the Moore clan
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My newer 70 Dart build started boiling the gas yesterday, BAD!

It has only the adapter from spread bore to square on it made of aluminum, and the headers are not ceramic coated. It gets hot in that engine compartment!

So, since I don't have a lot of room under the hood (383 in a 70 Dart), can anybody recommend a 1/4 inch spacer made of phenolic plastic or something similar?

I was thinking about using a 1/4 inch spread bore spacer then the adapter and then a square bore 1/4 spacer on top... Any thoughts? Or maybe just a square spacer half inch on top??? IDK
 
What kind of carb are you running? ThermoQuad? There's a much bigger selection of square-bore spacers out there than spread-bore and most of them are 1/2-1" thick. I put a 1/2" square bore wood fiber spacer made by Edelbrock on my 360 and it made a difference in hot weather. That also suffered from high underhood temps with uncoated headers, hopefully going to have them coated by a friend of mine for my 318 build I want to put back in.
 
make it out of marine plywood, really. Bakelite is just wood pulp.
 
1970dartcustom said:
My newer 70 Dart build started boiling the gas yesterday, BAD!

It has only the adapter from spread bore to square on it made of aluminum, and the headers are not ceramic coated. It gets hot in that engine compartment!

So, since I don't have a lot of room under the hood (383 in a 70 Dart), can anybody recommend a 1/4 inch spacer made of phenolic plastic or something similar?

I was thinking about using a 1/4 inch spread bore spacer then the adapter and then a square bore 1/4 spacer on top... Any thoughts? Or maybe just a square spacer half inch on top??? IDK
Click to expand...
This may work for you.
Order Products
 
Spacers of any material can be improved with a triangle shaped file. Make its vertical edges/sides look like VVVVVVVVVV . Nearly triples that surface area, thus more heat sink function.
 
If you look under the intake in my picture we took fiberglass insulation and wrapped it up in aluminum foil and painted it blue. For a heat soak. Look right under that ugly yellow coil I don't know if this would help you or not.
IMG_0113.JPG
 
I wrapped my headers really helped mine out. PIA to do in the car much easier if they are out.
 
RedFish said:
Spacers of any material can be improved with a triangle shaped file. Make its vertical edges/sides look like VVVVVVVVVV . Nearly triples that surface area, thus more heat sink function.
Click to expand...
That's actually brilliant :thumbsup:

Jeff
 
>you know gasoline begins to boil at around 95*, right? But it begins to evaporate at temps much below that. I have read tests that show 5% (by weight) of a given quantity of pump gas evaporating; in a 2 hr test at 70*and at 1 atmo.
>Have you got a mechanical fan on that puppy?
I like the 7 blade one. It may blow 200* air across your carb body, but that's a lot cooler than the 400*Plus coming off the headers. Plus with full-time operation, that same 200* air is pushing the 400* air down and out.If your lucky,you can end up with an average underhood temp of 250*
>How about ramming some fresh cold air down the carb? Atmospheric air above the hood,at ambient temp might be at 100* or less. That's a huge deal. I feel real sorry for an engine that has to suck in that 400* underhood air.
>Plus the engine makes a lot less power on that hot air. I always get a kick out of guys talking about keeping their fuel cool, but totally ignore the air temp thing.

Just FYI
I cut a hole in my hood and mounted a nice oval aluminum air filter on top of the hood, no scoop. Then I built a box under the hood and sealed the carb to the underside of the hood. That absolutely killed the tendency for hot running. That engine will now idle all day with a minimum running temp of 205*. The underhood temp,I'm sure could roast a pig in no time at all,lol. But the big DP is cool as a cucumber. But I don't run a paper filter,lol.
 
KrazyKuda (Carl) as the right part! That will work. I use that with all of my cars. Stops perculation of the fuel dead in its tracks 99% of the time. Even more so with the aluminum carbs. Holley or Carter designs.

Wrap your headers or have them coated. There is a BIG heat drop in doing so. Now your engine is feeling cooler and is ingesting cooler air as well. Home run!

Also see if you can't just get rid of the spacer. Edelbrock has an adapter plate that has a wider area to cover the spreadbore intake for use with there AFB / AVS carbs. It's designed for the Performer but can also be used on other spreadbore intakes.
 
Since you say you don't have a lot of hood clearance, block the exhaust crossover passages in the intake...makes a world of difference!
 
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The Edelbrock 5/16 thick gasket helped mine out a bunch. You can actually put your hands on the carb after its been running awhile and you shut it down.
 
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