phenolic vs wood carb spacer

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Tawny Demon

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I'm currently working on my car and I want to know for heat transfer and durability which is better spacer material I plan on using a open chamber regardless so what do you think also I've scene spacers comprised of a stack aluminum and gasket stacked up to make an one inch spacer so what's your opinions and experiences p.s. the car runs a cool can and a fuel bowl heat shield thank you for your help
 
wood is not a good material, very porous (allows air and liquid through grains) and very flammable when soaked in fuel
 
^^ Not to mention termites!!

I have seen quite a few racers at the track, most of them running custom sheet metal intakes, that are using wooden spacers. Probably because they can customize it quicker for their size & need. Idk.
For a street car however I'd rather use a phenolic or even aluminum spacer. I honestly dont know how they compare to wood as far as heat transfer & dissipation.
 
Phenolic probably would be safer and more durable but I would guess wood would have better insulating properties.
 
Canton has one it calls "phenolic". It looks like "wood". But that's what I've been using for many years with no issues. Whatever the actual material is, it doesn't seem porous. I also use the tapered 4-hole figuring it's a good compromise between a straight 4-hole and open spacer. This would probably have the best heat insulating qualities, certainly over aluminum. It would also appear to be less prone to warping from heat than the plastic appearing spacers. Canton also has other styles and materials.

http://www.summitracing.com/parts/ctr-85-158/overview/
 
Well they've made boats out of wood for hundreds? thousands? of years. Juz'sayin..............
 
There are phenolic plastic and phenolic wood spacers. The phenolic wood ones are a super-compressed laminate that seems to have some sort of sealer on it. I can't say which one would have better heat insulating properties. They both have to be better than aluminum.

I'm a slow typer. Locomotion got it right.
 
Most of the wood spacers are laminated, so they are not porous. But I have to ask. Are really serious? The difference if any at all between the two would be so minute you would be splitting hairs. Just pick one and go.
 
Wood is non conductive, and does not transfer hardly any heat. Phenolic material also does a good job at not transferring heat, but its kinda pricey. Aluminum is conductive, which transfers heat rapidly (making it a bad idea if you are having heat issues).

I listed these materials in order from best to worst for protection from heat transfer (wood being the best). The only bad thing about wood spacers is they can warp and wear out over time....that being said, I have had the same 1/2" wood spacer on my car for 13 years, no problems.
 
I would think hard maple, birch, poplar, or elm would work well. All are dense and fine grained. Start with seasoned wood. Laquer would be a good sealant.
 
I run a wood spacer (1/2" 4 hole) on the Scamp. Texas heat is tough anyway, much less having a 440 under that small hood area. Need all the help I can get. Seems to be helping so far, but a cool can may be finding it's way in there as well.
 
67Dart273 said:
Well they've made boats out of wood for hundreds? thousands? of years. Juz'sayin..............
Click to expand...
They also make aluminum boats too. So this got me thinking. :-k What else?
Wooden baseball bats- Aluminum baseball bats
Wooden ladders- Aluminum ladders
Wood siding- Aluminum siding
Wood Christmas trees- Aluminum (hey they weren't good ones but) Christmans trees
Wood patio furniture- Aluminum patio furniture
What else?..

I see a patterns here. Aluminum is trying to squeeze in on everything wood!
But plastics has them both beat! :tard:
 
RustyRatRod said:
Most of the wood spacers are laminated, so they are not porous. But I have to ask. Are really serious? The difference if any at all between the two would be so minute you would be splitting hairs. Just pick one and go.
Click to expand...

X2 to the above. I would stay away from the spacers/insulators that are stacked gaskets and aluminium plates. They can lead to cracked baseplates if you dont pay careful attention to your tightening sequence/torque.
 
flyfish said:
Wood is non conductive, and does not transfer hardly any heat. Phenolic material also does a good job at not transferring heat, but its kinda pricey. Aluminum is conductive, which transfers heat rapidly (making it a bad idea if you are having heat issues).

I listed these materials in order from best to worst for protection from heat transfer (wood being the best). The only bad thing about wood spacers is they can warp and wear out over time....that being said, I have had the same 1/2" wood spacer on my car for 13 years, no problems.
Click to expand...

Edit: I just checked prices (not having purchased a spacer in quite a few years), and phenolic spacers are not that expensive anymore, making it the best of both worlds (durable and insulates well). IMO, the best choice for the average Joe.
 
Wooohooo. Now we're debating. Being an old hardwood flooring guy, it's just a no brainer to make a wood spacer. Plus I already have marine grade polyureathane (think Bar Top) for the cut edges. I also am a little leary of the sealing capabilities of phenolic as evidenced by all the Thermoquads I haev owned over the years. Thanks for all the input!
 
The wood spacers that I'm familiar with are not merely coated in a sealer, they are pressure treated. In the end they aren't much different from the phenolic spacers. They only differ in the type of volume filler. Phenolic resin w/o much filler, like in a ThermoQuad, wouldn't be very stable. Linen Micarta is very stable and is linen sheets laminated with phenolic resin. Also works good for low speed, high load bushings.

I've found that a heat shield, ala the fabled DZ-302 Z-28 part, made from 1/8" aluminum to work very well when moving the carb up due to a spacer means a hole in the hood. The one that I made was the length and width of the intake manifold.
 
Moparmarcus said:
Wooohooo. Now we're debating. Being an old hardwood flooring guy, it's just a no brainer to make a wood spacer. Plus I already have marine grade polyureathane (think Bar Top) for the cut edges. I also am a little leary of the sealing capabilities of phenolic as evidenced by all the Thermoquads I haev owned over the years. Thanks for all the input!
Click to expand...

The only Thermoquads that had warping problems were those used on cars with catalytic converters where underhood temps were so hot they warped the plastic bodies. They are plastic, not phenolic. They got a bad rap because they were used more so on emissions vehicles when their potential was so much greater.
 
OK, time for the degreed chemist and 27 year aerospace engineer to chime in.

Moparmarcus, it is best not to use a polyurethane coating in fuel applications unless it is rated for it. Not all polyurethanes are equal and they can swell and begin to break down when exposed to fuel.

Everybody, phenolics are a type of plastic that have widespread use for fuel applications because they are inert to gasoline and they are also thermo-insulating. They don't transfer heat and they are stable at high temperatures. In fact, one particular type of phenolic plastic is used as a re-entry heat shield on space capsules.

A phenolic impregnated wood spacer has the excellent insulating property of wood while having the fuel resistance property of a phenolic at a lower cost than an all phenolic spacer. Either one is better than an aluminum spacer when one wants to keep the fuel mixture at a lower temperature before it reaches the intake.

Art
 
Just pointing out that an aluminum spacer and an aluminum plate function in two entirely different ways. Aluminum is very good conductor of heat, which makes it a poor insulator if the goal of a spacer is thermal insulation as well as an increase in plenum volume.

Being that excellent conductor of heat, an aluminum plate acts partly as a radiator, drawing the heat out of the intake manifold and radiating it into the atmosphere, and partly as a shield blocking the heat radiated off the engine from reaching the carb.

I'll venture that most truly street engines won't respond favorably to an increase in plenum volume and that a spacer, even a 4 hole spacer, is a step in the wrong direction for them. A street/strip engine and/or a strip engine probably will respond favorably to a spacer.
 
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