Single Carb Conversion: Adapt the stock plenum

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OK stupid idea #1

It involves taking 4ea of pieces of the same alum. tube for the new runners.

Put them inside the plenum, with each tube going toward its runner path then the center of each tube cut down lower, making a plenum inside of a plenum.

with the center a hole opened to all runners

Epoxy around the whole mess to fill in the voids.
 
Ok enough hair brained ideas.

I am going to go for it, I will pick up some material.

Tomorrow, and get started.

A long the way If i or someone else can figure out a way to reduce the volume, that sounds like ti is a good idea.

I will implement it.

I will this Rev.#B as prototypes usually have letters.

My drill/mill still needs a new male plug on the cord, it dont match my receptacle
 
Are two mounting holes going to be enough to mount a carb & base plate and provide Zero vacuum leaks?

It would be much more secure to have 4 mounting holes.

But i said i would not weld!!
 
I said I would not weld!

But a couple pieces of alum. in the bottom of the manifold, to bring the plenum floor up to the level of the raised bump to make the plenum floor flat.

I could raise my runners to the top of the plenum outlets. this would make the plenum floor flat and reduce some of the volume.

That raised part Inside, and on the plenum floor is about a 1/2" high, multiply that times the length of the plenum floor
 
Yes is do.

I was thinking of using a piece of vacuum hose or fuel line slit the length on on side, spread that apart and over the rim of the plenum top.

but use some black high temp RTV under the hose and in between the joint.

and use that as a seal I can make it the thickness i need, if the oem air box seal does not make a good enough seal

[url=https://www.classicgoldwings.com/forum/viewtopic.php?p=97288#p97288:3bxasdda said:
joedrum » Mon Sep 23, 2013 12:34 pm[/url]":3bxasdda]
a seems if you had a airbox gasket yes
Click to expand...
 
If I were going to weld a 1/4"-1/2" thick alum. plate or whatever thickness into the bottom of the plenum.

I might as well, weld in 2ea more mounting blocks.

While i am at it do a seam weld around the two split halves, and make it one piece, then no seal is needed between the two halves.

Welding the Floor spacer plates would make it in to one piece but you would not be able to replace that seal unless pieces were cut in half and then welded in the floor for each half.

[url=https://www.classicgoldwings.com/forum/viewtopic.php?p=97290#p97290:1yazn6jq said:
westgl » Mon Sep 23, 2013 12:40 pm[/url]":1yazn6jq]
I said I would not weld!

But a couple pieces of alum. in the bottom of the manifold, to bring the plenum floor up to the level of the raised bump to make the plenum floor flat.

I could raise my runners to the top of the plenum outlets. this would make the plenum floor flat and reduce some of the volume.

That raised part Inside, and on the plenum floor is about a 1/2" high, multiply that times the length of the plenum floor
Click to expand...
 
That plate that you could weld into the Plenum floor

What if it was two different sizes?

Say at the opening for each runner, lay in 1/4" alum plate.

I remeasured that bump that is in there now it is 5/8" High,

Take the plenum, look inside, In the middle between the front and rear cylinders, is that raisde bump some sort of a vacuum port going through there that we would not use

That raised part that is centered, could be a center ramp, that reduces volume, using 5/8" high tapered between the cylinder and only in the center may work.

I could put a 1" high alum. bar that looks like a pyramid right down the split line of the plenum, that would reduce the volume, if it was 3/4" - 1" wide
 
Some math

It is a 2" opening, this reduced some as to avoid anything in the path.

2" from as high as i can go (may get 2-1/8" out of it) allowing for 1/4" at bottom

a couple pictures that show where i would put some volume reducing alum. to reduce air volume.

Each measurement you see, represents the approximate thickness of material.

That 1/4" on the sides may be 3/16" - 1/2" will work better

P1020091

P1020091

2nd Plenum Volume reducer

P1020090

P1020090

2nd Plenum Volume reducer
 
For the plenum floor how about a piece of flat alloy sheet that has a fold in the centre line and ends up tapering down to the carb runners. An upside down V or with a little curve like a skaters half pipe..
 
Thank you Ansimp,

Good idea.

Yes

So I could put in a piece of bent sheet metal thick enough to be really tough,

If done right, it could hold itself in place.

I am not sure, and hesitant to use adhesives, in a fuel Environment, I dont think JB weld is fuel proof.

Or


Some alum. sheet bent in the middle, to look like a upside down V.

That would defiantly reduce the air volume of the inside of the Plenum without piecing a lot of different blocks together.

With the block method I could still get the two half's of the manifold plenum apart.

With a inverted "V" may have to go the welded two Plenum half's together.

With the 8ea Grade #8 mounting bolts (No Chinese made bolts here) from the inside facing out to attach the two plates holding the tubes to the out side of the plenum.
 
Hey, theres room to drill and tap some NOS fogger nozzles.

Nice photos. looks like some JB Weld time is needed. We have used JB Weld around manifolds and on the inside of carbs before. Now would I place it in a puddle of standing fuel for years, NO. But after cleaning the bottom of a dry gas tank it has been put on a penny and stuck over a pin hole.

Edited
 
I`m just throwing this out but maybe the floor could be poured. They use a liner material for our rusted tanks, perhaps it could be used to raise the floor, even still if it can be worked this way why not use it to form a plenum of whatever size by using a block of Styrofoam cut to size, placed inside then an epoxy poured around it, afterwards just chip out the Styrofoam.
Lots of gas resitant epoxy here too.
https://www.aircraftspruce.com/pdf/2011I ... t11158.pdf
 
All good ideas.

I just received another 32DFT from Tom, today.

I think I have been refueled, by this last few details of our conversations.

I am thinking this can work, and work well.

Lets see, wife has a good 1/2" wide bread board to bend the S.S, or Alum. sheet over,

I will try and make myself out a grocery list, and do some metal shopping tomorrow.

I guess i am the guinea pig on this one.

No problem!!

I look forward to it.

But it may take me a few days as i will have to get a cord end on my drill/mill.

And whatever tools i dont already have ie: Drill bits, hole saw the correct size, maybe a tap
 
Another option to the pour idea would be to use cardboard tubes like on paper towel rolls or TP rolls, stick them into the four openings and pour the floor, when it dries just peel/soak the paper out.
I really have no idea how that liner stuff pours or holds up but it seems to stick to the inside of tanks and holds up to fuel.
 
Wes, I was wondering if you could furnish the internal length, width and height of the 1100 plenum. Also the same of the vw plenum if not to much trouble, I'm doing some work with the 1200 plenum and need some info to compare with and I don't have the 1100 or vw plenum to measure myself.
 
Ok a few pictures of the 32DFT carb. that i received from Tom today.

I set the 32DFT on the GL1100 Plenum for you to get a good look at the two together

So you can see what it looks like and the size comparison between the

32DFT & the
32/34DFT

P1020092

P1020092

Weber 32DFT on the GL1100 plenum

P1020093

P1020093

Weber 32DFT on the GL1100 plenum

P1020094

P1020094

Weber 32DFT on the GL1100 plenum

P1020095

P1020095

Weber 32DFT on the GL1100 plenum

P1020096

P1020096

Compare 32DFT 22/22 to a 32/34DFT 24/25

P1020097

P1020097

32DFT on Left 32/34DFT on Right

P1020098

P1020098

32DFT Left, 32/34DFT on Right

P1020099

P1020099

32DFT

P1020100

P1020100

32DFT

P1020101

P1020101

32DFT
 
well my my arnt we all thinking ... sheesh you guys are starting to think like me ....I bet that scary ....

well for financial reason of having this Honda air boxes all around me ....im in ... plus the fact I have two solex carbs coming to try ....after seeing jungos work take right off im convinced this carb will good .....and this is my best hope to get it together ... I think im not going to over think it at this point ...just put it together and see where im at ....when I try to run it ...pretty much my way of doing things ....if things need to be close in it will happen ..there many options ... but mine are limited to the amost fundless category .... im not worried at all about that part ..so ilke this thread and i lilke all involvement
 
Here is the bottom of the 32DFT

Tom has included a carb to manifold Gasket

Here is a picture of it

P1020102

P1020102

Bottom of 32DFT showing gasket
 

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