Single Carb Conversion 2 Barrel Progressive Holley,Weber 740 carb

[Ansimp]

Great results :good:

 

[82a]

Brian» Fri Oct 11, 2013 2:16 pm[/url]":rwmxpxzd]
OK the die has been cast and I have made my commitment; just ordered a pair of 1 1/4" x 18" Moen grab bars. I ordered them from amazon at $22 each with free shipping so that wasn't too bad.

I have some different ideas about the flange at the head and the way the runners meet up with the plenum...will keep you posted.

opcorn: opcorn: :moped:

 

[82a]

Jungo » Fri Oct 11, 2013 2:48 pm[/url]":3slagnuj]
Jungo,

What setup are you using? Grab bars? 1 1/4" or 1 1/2"?
I have looked but cannot find where you describe it.

viewtopic.php?p=97092#p97092

 

[Jungo]

Brian:
My runners are 1 3/16" ID (1.1875" ID).

 

[canuckxxxx]

Jungo » Fri Oct 11, 2013 7:19 pm[/url]":fdl33p2m]
Brian:
My runners are 1 3/16" ID (1.1875" ID).

Thanks for the info Jungo. I am going to use the 1 1/4" grab bars so the ID of my runners should be similar to yours. It is very encouraging that the small ID runners worked so well for you.

How is the top end power; from say 5000 to 8000 RPM with the throttles wide open?

Brian

 

[canuckxxxx]

82a » Fri Oct 11, 2013 5:00 pm[/url]":3murwfpj]

Brian» Fri Oct 11, 2013 2:16 pm[/url]":3murwfpj]
OK the die has been cast and I have made my commitment; just ordered a pair of 1 1/4" x 18" Moen grab bars. I ordered them from amazon at $22 each with free shipping so that wasn't too bad.

I have some different ideas about the flange at the head and the way the runners meet up with the plenum...will keep you posted.

opcorn: opcorn: :moped:

I need to get my grab bars in my hands to know for sure. I thinking that the flanges on the grab bars look fairly thin so I might not be able to screw them down very tight before they distort. So I am going to either make my own flange plates, out of 1/4" thick flat steel, or buy some from some source like a muffler shop. That is, a plate cut the shape of the port flange on the head with 2 bolt holes and a 1 1/4" hole. This flange plate will slide over the runner and clamp the runner flange down against a gasket. The grab bar flange would be trimmed back to less than the distance between the hold-down bolts.

Besides giving good clamp down it would allow the runner to rotate. I am thinking that when all 4 runners are clamped to the VW manifold using rubber couplers the manifold will go to some orientation that is probably not straight north-south. I will clamp it all together loose before I tighten down the flange plates so there is no twisting tension on the flanges.

At the VW manifold end I want the grab bar ID to carry right through to the plenum. The 1.4" ID part of the plenum spigot is about 1" long then is goes down to 1 1/4" at the plenum. I will cut a piece of grab bar 1.5" to 1.75" long and push it into the plenum. Not sure how tight a fit that will be; ideally it will be a slight interference fit to hold the short piece of runner in place. I will put some kind of spacer between the runner and 1.4" part to keep it centred. This short piece will be sticking out of the spigot by .5" to .75".

I need to find a some fuel rated hose that is 1 1/4" ID and 1 5/8" OD that will join the runner from the head and the short piece of runner at the manifold. Then I will use a regular 1 1/2" rubber plumbing coupler to clamp the fuel hose to the OD of the manifold spigot.

Anyways this is all in my head right now. Will see how it looks when I get my grab bars and if I can find some fuel rated hose the right size.

Brian

 

[slabghost]

could probably use flange plates for one of the inline 4 bike exhaust. Something for a 550 or 650 cc might be a close match.

 

[joedrum]

Jungo » Sun Sep 22, 2013 7:14 pm[/url]":22kog0yp]
My runners are ready. This is what I did:

As Westgl, I considered EMT pipe but I found that 1 1/4" was too difficult to bend, since the distance is too short. Walking in Home depot I saw a top rail pipe to use in link fences. 1 3/8" x 10' @ $10.95. This pipe fits almost perfectly in the VW plenum.

So I cut a 5" pipe and installed on the port #3. Piece of cake... so far.

20130922 151954

• Jungo
• Sep 22, 2013

20130922 152851

• Jungo
• Sep 22, 2013

Now the big challenge, how to bend the pipe to fit the port #1. After use my 1" EMT pipe bender I notice that this kind of pipe was made not to bended and I destroy the conduit. :head bang:

Then I cut a 7" piece of pipe and made 2 "V" cuts so I can bend and make an "S".

20130922 154758

• Jungo
• Sep 22, 2013

A friend of mine bring his wire solder and fix the "v" cuts I made to the pipe.

20130922 160744

• Jungo
• Sep 22, 2013

Then I clean it with a grinder. Voila!

20130922 165427

• Jungo
• Sep 22, 2013

Look how it looks once installed

20130922 163241

• Jungo
• Sep 22, 2013

Both sides are ready:

20130922 173653

• Jungo
• Sep 22, 2013

Tomorrow I'll receive the adapter for the 34PICT carb. :yahoo:

[video]https://youtu.be/zcEyVGo9ceE[/video]

I beleave in going with the jungo method ...its obvious to me this the easiest and cheapest way to hook up the type 4 manifold ....jungo offered to build a set set for me to use an hooch and I accepted it ....you can see it uses the type four transition ferrules to connect ...the size is right ..and a 10fr section of pipe makes a lot of runners ....

I think all other methods being talked about and done are great ....and maybe better who knows ...but its apparent to me that the bends in the runners are not really a real problem as compared to other things ....so the jungo approach is mine ... :builder: :mrgreen:

 

[canuckxxxx]

slabghost » Fri Oct 11, 2013 11:30 pm[/url]":1tkguzl5]
could probably use flange plates for one of the inline 4 bike exhaust. Something for a 550 or 650 cc might be a close match.

Good point Slabghost. I should have thought of that because my old GS750 had those kind of flange fittings.

There is a motorcycle wrecking place in town maybe I will nose around there with my calipers and see what I can find. The bolt holes need to be 60mm apart and >1 1/4" hole in middle.

Thanks for that
Brian

 

[westgl]

I would think the thickness of the SS flange is fine.

The main concern, is the seal between the Flange and the head.

A gasket of sufficient thickness, and sealing quality.

A seal that can handle heat.

A seal that will NOT leak.

I would use a thicker seal that was coated with Ultra Black.

Clean contact areas VERY GOOD

I have used Ultra Black for Header seals, the Manufacturer Recommended the Ultra seal, instead of ANY header to head seal or gasket.

They were Sanderson headers, very high quality headers.

The thing about using Ultra black is to go by the recommended application, put on a bead tighten until you make light contact with the bead then let sit for the time frame specified for the Ultra Black to tack up and harden slightly, then tighten down/torque bolts

You may be able to use the Ultra Black Only without any other gasket, as it will form to what ever seal you need.

I would make Vacuum leak detection with any single carb setup, part of your maintenance schedule.

Maybe like brake fluid replacement every two years.

I would check it every 6 months for the first year, though

 

[ianstaley]

So after reading this stuff (most goes over my head right now) I have taken the plunge and bought the VW centre section Plenum £61 delivered in the UK, I don't need it right now, but like everything in this world it is only getting more expensive every day. So buy it now some money later when I do need it. so watching this very close. I am still not sure which carb to go for. The CT type solex is quite cheap even new, whereas the Webber is very expensive here and of course mine is your standard GL1000 from 79. So by the time I get to do this over here in the cold UK the problems with jets will be pretty much solved. Everything is so cheep in the US $90 delivered for a carb is theft man.... I can only dream. As for the sealant, vitron seals are fine with gas and can take the newest fuel types with I think methanol in it. but in the reply above sounds like we used to do on the boat with Sikaflex sealant just sit a bead on one side that you want to seal, just get both sides to slight squeeze the Sikaflex leave for about 4 hours till it get a bit of a dull skin on it the tighten, forms a perfect seal.

 

[82a]

tbi option
https://www.jenvey.co.uk/

 

[canuckxxxx]

westgl » Sat Oct 12, 2013 8:09 am[/url]":2d86la0c]
I would think the thickness of the SS flange is fine.

The main concern, is the seal between the Flange and the head.

A gasket of sufficient thickness, and sealing quality.

A seal that can handle heat.

A seal that will NOT leak.

I would use a thicker seal that was coated with Ultra Black.

Clean contact areas VERY GOOD

I have used Ultra Black for Header seals, the Manufacturer Recommended the Ultra seal, instead of ANY header to head seal or gasket.

They were Sanderson headers, very high quality headers.

The thing about using Ultra black is to go by the recommended application, put on a bead tighten until you make light contact with the bead then let sit for the time frame specified for the Ultra Black to tack up and harden slightly, then tighten down/torque bolts

You may be able to use the Ultra Black Only without any other gasket, as it will form to what ever seal you need.

I would make Vacuum leak detection with any single carb setup, part of your maintenance schedule.

Maybe like brake fluid replacement every two years.

I would check it every 6 months for the first year, though

Sounds interesting West. Is Ultra Black the product name? Is it available at auto stores?

Brian

 

[82a]

Permatex Ultra-Black Sealer

 

[slabghost]

FelPro has gaskets that will fit and you can make your own from gasket material or non corrugated cardboard. No need for RTV or silicone sealers.

 

[westgl]

When you look at the bottom of the flange.

Put a straight edge across the flange several different directions, front to back side to side, so on.

You want see how Flat the bottom of the flange is.

Sometime the heat from welding can distort metal.

If it is very Flat then a gasket should be fine, you will have to determine the thickness, and type of material.

Or if there is a raised section under the flange.

But if do to welding, it has a slightly bent flange or it is concave and not flat, even after you have torqued it down, and checked again for flatness, and after you removed it, you may need to use a something to fill the voids like Ultra black.

 

[shovelking81]

I used the ultra black and the fel pro gaskets, glue the gasket to the head with a very thin coat and let it dry so it doesn't slip, apply a thin coat to the runner side and bolt it down, no leaks, the thin flange is not a problem, it is designed to carry 500 lbs on the bar, there is very little load on these as an intake, it should never cause a problem...... :thanks:

 

[ianstaley]

I have been doing a bit of research and found this stuff looks very promising when soldering take a look guys.

1) is called Durafix see here for a demo vids https://www.youtube.com/watch?v=G92QIMyX ... 2D3BB3FE08

an other type is called Super Alloy 5 rod and flux see here https://www.youtube.com/watch?v=yqkceLrH9Ao

once you have decided on angles ETC you could finalise parts of it by soldering the ally.

 

[joedrum]

hmmmm great videos.....im sure soon were going to see this kind of work soon on the simgle carb deals ...as they get perfected

 

[ianstaley]

The durafix looks a lot cheaper than the super alloy 5 both seem to be a massive move forwards regarding welding or soldering tubes together. especially of you go down the aluminium tube route.