Carburetor spacer

[blackhawkxx]

Anyone ever make a carb spacer of of wood for a auto four barrel?  I would like to play with different ones and thought I could make them.  Would regular plywood be the right choice?  How could I make sure it was truly flat without a planer?  Just kicking this around.

[IcePrick]

I've seen a few of them, but never made one myself.  Seems sort of low-budget to me, but they did function.  I never questioned the "why", just guessing that someone was impatient to do a startup on a long project and didn't have the right spacer (or none at all)... bang something out with the scroll saw and drill press, it works so never changed it? 

 

Maybe plywood as a proof-of-concept if it's an experimental configuration, then make a final product out of phenolic resin laminate.  I would guess you can work the latter with woodworking tools, maybe with some speed adjustments and/or cooling/lubrication.

[XXitanium]

Are you trying for mire down draft?

[blackhawkxx]

6 hours ago, IcePrick said:

I've seen a few of them, but never made one myself.  Seems sort of low-budget to me, but they did function.  I never questioned the "why", just guessing that someone was impatient to do a startup on a long project and didn't have the right spacer (or none at all)... bang something out with the scroll saw and drill press, it works so never changed it? 

 

Maybe plywood as a proof-of-concept if it's an experimental configuration, then make a final product out of phenolic resin laminate.  I would guess you can work the latter with woodworking tools, maybe with some speed adjustments and/or cooling/lubrication.

I have been reading and watched Engine Masters (best program ever) about carb spacers and their affect on different engine combinations.  They have open, divided, four hole, four hole tapered, 1/2", 1", 2" etc.  They act differently on single plane/dual plane intakes.   At about $50 a pop to buy the cheap ones, I thought maybe I could find out what my engine wants with wood.  If you check Summit Racing, many say they are made of wood but now that I went back and checked the details, it says Phenolic wood so I guess it isn't really wood after all.   

[Furbird]

Wood is a BAD idea for any sort of live test, especially plywood.  You have different, unknown species of woods pressed together in a sandwich with exposed end grains with unknown glues exposed to fuel and vacuum.  This is also unfiltered and you're sucking God-knows-what into your engine.  That doesn't even take into account the fire factor. 

[superhawk996]

11 hours ago, blackhawkxx said:

How could I make sure it was truly flat without a planer?

I don't think flatness would be much of a problem, as long as the wood isn't visibly warped.

 

11 hours ago, blackhawkxx said:

Would regular plywood be the right choice?

I'd be concerned with wood particles going into the engine, especially if the gas and/or heat start breaking down the adhesive in the plywood.  I'd try to find a plastic that'll hold up, or maybe just regular lumber.  Also beware that anything compressible will let you bend/break the corners of the carb if you over-tighten it...ask me how I know 😑

 

The power differences will probably be too small to detect on the butt dyno unless your combination really needs something and you happen to make that thing.  If you can mark off a stretch of road and do repeatable testing it might show the changes.

 

What motor and how built is it?

[superhawk996]

A thought just hit me, you could probably make plywood pretty safe if you epoxy coat it.  MDF is another option to consider.

[SwampNut]

MDF and a sealant.

 

Or plastics like HDPE (King Starboard).

 

[blackhawkxx]

4 hours ago, superhawk996 said:

I don't think flatness would be much of a problem, as long as the wood isn't visibly warped.

 

I'd be concerned with wood particles going into the engine, especially if the gas and/or heat start breaking down the adhesive in the plywood.  I'd try to find a plastic that'll hold up, or maybe just regular lumber.  Also beware that anything compressible will let you bend/break the corners of the carb if you over-tighten it...ask me how I know 😑

 

The power differences will probably be too small to detect on the butt dyno unless your combination really needs something and you happen to make that thing.  If you can mark off a stretch of road and do repeatable testing it might show the changes.

 

What motor and how built is it?

302w, good heads, cam etc.  The thought of compressible corners did occur to me as years ago an unsupported corner of a intake manifold snapped.  I have been running a divided spacer on a dual plane but it was shocking (to me) the HP difference a spacer can make at least on the dyno from the Engine Masters program. 

This was just a thought and might just buy another to try down the road.  I have always heard of people doing it but never tried it.  

 

[XXBirdSlapper]

Are you intentionally trying to start a full blown car fire?

[blackhawkxx]

5 hours ago, XXBirdSlapper said:

Are you intentionally trying to start a full blown car fire?

Yes, one in each of the eight cylinders.

[XXBirdSlapper]

2 hours ago, blackhawkxx said:

Yes, one in each of the eight cylinders.

A gasoline saturated block of wood directly under a gasoline container with additional fuel being delivered under pressure is going to turn the whole engine compartment into barbecue pit. There's a reason they use materials that don't absorb gasoline.

[superhawk996]

On 8/20/2023 at 11:16 AM, blackhawkxx said:

302w, good heads, cam etc.  The thought of compressible corners did occur to me as years ago an unsupported corner of a intake manifold snapped.  I have been running a divided spacer on a dual plane but it was shocking (to me) the HP difference a spacer can make at least on the dyno from the Engine Masters program. 

This was just a thought and might just buy another to try down the road.  I have always heard of people doing it but never tried it.  

 

Which intake?

I ran an open spacer on my mostly stock 351C and it seemed to make an improvement, but I never really tested it.  The spacer I had was adjustable, it was made of layers of thin aluminum plates and gaskets.  It was mildly compressible when stacked tall and how I learned about fucking up a carb.  I ran a 650 double pumper which 'shouldn't' have worked well, but did.  I may still have that spacer, I'll try to look later.

 

The most impressive spacer I used had two brass rods in it connected to solenoids 🙂

[blackhawkxx]

7 hours ago, superhawk996 said:

Which intake?

I ran an open spacer on my mostly stock 351C and it seemed to make an improvement, but I never really tested it.  The spacer I had was adjustable, it was made of layers of thin aluminum plates and gaskets.  It was mildly compressible when stacked tall and how I learned about fucking up a carb.  I ran a 650 double pumper which 'shouldn't' have worked well, but did.  I may still have that spacer, I'll try to look later.

 

The most impressive spacer I used had two brass rods in it connected to solenoids 🙂

Weiand Stealth.  Years ago I also had what sounds like the same spacer but the bottom plate was a lot wider (not taller) and it displaced the heat from getting to the carb.  The multiple gasket was a pain. 

[Zero Knievel]

On 8/20/2023 at 11:06 PM, XXBirdSlapper said:

A gasoline saturated block of wood directly under a gasoline container with additional fuel being delivered under pressure is going to turn the whole engine compartment into barbecue pit. There's a reason they use materials that don't absorb gasoline.

 

Well, it would work for a test fitting and brief testing.  If it's right, use it as a template for one made of better materials.

[XXBirdSlapper]

6 hours ago, Zero Knievel said:

 

Well, it would work for a test fitting and brief testing.  If it's right, use it as a template for one made of better materials.

Or you could just buy a proper one and not fuck around.

A friend of mine in manufacturing machined one for his race car, and began producing them. It's in his office as a paperweight as the Chinese copies flooded the market at a price he can't get close to matching. I recall them readily available for many automotive applications 35 years ago.

[Zero Knievel]

7 hours ago, XXBirdSlapper said:

Or you could just buy a proper one and not fuck around.

A friend of mine in manufacturing machined one for his race car, and began producing them. It's in his office as a paperweight as the Chinese copies flooded the market at a price he can't get close to matching. I recall them readily available for many automotive applications 35 years ago.

Why would you waste valuable materials making the test version?

[XXBirdSlapper]

6 hours ago, Zero Knievel said:

Why would you waste valuable materials making the test version?

Not following you. Waste valuable materials? Who did that?

[Zero Knievel]

3 hours ago, XXBirdSlapper said:

Not following you. Waste valuable materials? Who did that?

Well, you criticized using wood to make a draft piece.  I say it would be fine to attain the desired shape and size…then use it as a template for making it from better materials.  Unless you can re-smelt metal at home, why waste a good piece of metal when you haven’t determined the final form?

[XXBirdSlapper]

3 hours ago, Zero Knievel said:

Well, you criticized using wood to make a draft piece.  I say it would be fine to attain the desired shape and size…then use it as a template for making it from better materials.  Unless you can re-smelt metal at home, why waste a good piece of metal when you haven’t determined the final form?

The final form was created on the CAD file. Have we regressed to the days of wood pattern making??

[blackhawkxx]

Forget it guys, I was just thinking out loud.

[superhawk996]

On 8/22/2023 at 11:48 AM, blackhawkxx said:

Weiand Stealth.

I remember that name from way back.  From rusty memory, they had a pretty good following.  No clue how well they stack up against Edelbrock or others.

[XXitanium]

https://jomarperformance.com/collections/phenolic-carburetor-spacers

 

[blackhawkxx]

7 hours ago, superhawk996 said:

I remember that name from way back.  From rusty memory, they had a pretty good following.  No clue how well they stack up against Edelbrock or others.

Somewhere down the road I may switch over to a Edelbrock RPM Air-Gap intake.  From the dyno test I've seen, it has almost as much peak HP but a stronger midrange.  I did order a Edelbrock open spacer to try.

[superhawk996]

6 hours ago, blackhawkxx said:

I may switch over to a Edelbrock RPM Air-Gap intake

That was my thought.  There's a single plane that seems to work quite well throughout the RPM range, Victor JR. I think.

 

What you really need is a pair of Cleveland 4V closed chamber heads.  Checks shed....yup, just sitting here waiting for something to bolt to 😇