Single Carb. Conversion, VW Plenum & Modding, the OEM Manifolds

[westgl]

I do Not have a lathe,

I have a chop saw, I bought tubing the correct OD and ID, then cut it 3/4" long, then took a file to bevel the opening to a 1-1/8" opening, so that it would funnel the charge into it smoothly.

Yes and No as far as heat goes, I removed the Radiator heat shield between the radiator and air Filter, the air filter can get heated air for air intake,

I have been playing with a shroud to go around the air filter to better collection the radiator heat to use it as Heated air intake.

This helps a lot, I have a Heater/support bracket that is connected to the engine block that provides some heat to the bottom center of the plenum.

I also have been thinking of using a heated carb. spacer, it has coolant going through it, and mounts between the carb and plenum.

Where are you located?

Do you ride in less then 40 degree weather?

canuckxxxx » Fri Oct 04, 2013 5:54 am[/url]":3sn61sfn]

westgl » Thu Oct 03, 2013 5:52 pm[/url]":3sn61sfn]
Yes I put in 1"ID chokes, that opened up to 1-1/4" ID tubing.

The Plenum has been opened up to 1.400" ID in the Outlet, going further up into the outlet, before where they have been opened up, you can see they measure approx 1.0" - 1-1/16".

So my choke reduces the ID size of that transition, from 1.400"ID down to 1.0" id, to speed up the air/fuel charge speed.

When I did rev.2 with No chokes and 1-3/8"ID tubing, the charge speed, seemed to be the cause of the bike falling on it's face, from a dead stop and having some hesitation.

When I did rev.2.2 just adding the chokes it was much better, but still had some hesitation.

Rev.1 did not have any hesitation, the ID on the hose was reduced down to 1.100" ID, but it did not have any chokes, Rev.1 mid range to top end was not as good as Rev.3.

But i noticed some hose collapsing, which may have reduced down My ID even further, and speed up of the charge may have taken place.

I can see how the choke would speed up the air and keep the fuel atomized.

Are these chokes something you make yourself on a lath? or can you buy them? Could the same affect be had by putting an orifice plate at the exit of the plenum, that is a 1.4" OD washer with various sizes of hole sandwiched between the manifold runner and the end of the plenum spigot. That would be much simpler.

Right now REV 3 is unheated right? When I ordered my carb. from Tom Langdon he really stressed the need for lots of heat on the plenum and runners in order to keep the fuel atomized. Perhaps if you had lots of heat applied you wouldn't need the chokes.

Maybe, with no heat and no chokes, it is like an engine that is not warmed up, that is, hesitation and flat spots.

Brian

 

[westgl]

That plenum is very small inside, the floor is raised up in the center to reduce volume, it almost looks like bent tube runners in side going to the outlets, as the fuel charge starts to leave the outlets the outlets are kept small sized,

Until the charge gets to the machined outlet area where it opens up into 1.400", that is why I reduced that down to 1.050"ID to keep the charge moving fasst!

That plenum is a small volume for good speed, now just tuning it some.

ekvh » Fri Oct 04, 2013 6:09 am[/url]":28my9fi7]
At this point, it seems that the only mods that have worked without some sort of negatives are the ones using the vw type iv intake. Perhaps there is something to the collector inside the plenum which funnels the charge and keeps it moving down the tubes? I'm sure there is something that can be done with these other mods using the stock plenum, but at $60 versus all the labor involved in the other mods using the stock plenum, it looks to be the best and safest bet. I enjoy reading all the experiments.

 

[westgl]

Here is the ford heated spacer plate, I am going to try and use heated air and my heater plate, using engine block heat, at this point.

Dis-regard the carb. as it has nothing to do with anything.

Canada, gets a little cold than where I'm at, and lasts a little longer too.

Ford Coolant heated Spacer plate

• westgl
• Oct 4, 2013

Ford Coolant heated Spacer plate

 

[canuckxxxx]

ekvh » Fri Oct 04, 2013 7:09 am[/url]":l07e1l9u]
At this point, it seems that the only mods that have worked without some sort of negatives are the ones using the vw type iv intake. Perhaps there is something to the collector inside the plenum which funnels the charge and keeps it moving down the tubes? I'm sure there is something that can be done with these other mods using the stock plenum, but at $60 versus all the labor involved in the other mods using the stock plenum, it looks to be the best and safest bet. I enjoy reading all the experiments.

I like the fact that I can keep the complete OEM carb assembly as-is in case this doesn't work out.
Brian

 

[westgl]

I agree with you Brian, it is a unknown for you, and you are skeptical.

If it does work out for you, say after a couple of riding seasons, you can sell the OEM carb rack for some extra $$ on fleecebay, I mean Ebay.

But after you try it, you will be hooked.

canuckxxxx » Fri Oct 04, 2013 6:49 am[/url]":dsok62lo]

ekvh » Fri Oct 04, 2013 7:09 am[/url]":dsok62lo]
At this point, it seems that the only mods that have worked without some sort of negatives are the ones using the vw type iv intake. Perhaps there is something to the collector inside the plenum which funnels the charge and keeps it moving down the tubes? I'm sure there is something that can be done with these other mods using the stock plenum, but at $60 versus all the labor involved in the other mods using the stock plenum, it looks to be the best and safest bet. I enjoy reading all the experiments.

I like the fact that I can keep the complete OEM carb assembly as-is in case this doesn't work out.
Brian

 

[canuckxxxx]

westgl » Fri Oct 04, 2013 7:14 am[/url]":2de8dovk]
I do Not have a lathe,

I have a chop saw, I bought tubing the correct OD and ID, then cut it 3/4" long, then took a file to bevel the opening to a 1-1/8" opening, so that it would funnel the charge into it smoothly.

Yes and No as far as heat goes, I removed the Radiator heat shield between the radiator and air Filter, the air filter can get heated air for air intake,

I have been playing with a shroud to go around the air filter to better collection the radiator heat to use it as Heated air intake.

This helps a lot, I have a Heater/support bracket that is connected to the engine block that provides some heat to the bottom center of the plenum.

I also have been thinking of using a heated carb. spacer, it has coolant going through it, and mounts between the carb and plenum.

Where are you located?

Do you ride in less then 40 degree weather?

I live in Calgary Canada and I ride right down (to close) to freezing. But not very much.

The way Tom was talking you have to put a lot of heat to the plenum and runners to keep the fuel atomized. He thought that only circulating engine coolant could provide that much energy. I think he is right for an uninsulated setup but you could get away with much less heat applied if you insulated the plenum and runners.

Brian

canuckxxxx » Fri Oct 04, 2013 5:54 am[/url]":2de8dovk]

westgl » Thu Oct 03, 2013 5:52 pm[/url]":2de8dovk]
Yes I put in 1"ID chokes, that opened up to 1-1/4" ID tubing.

The Plenum has been opened up to 1.400" ID in the Outlet, going further up into the outlet, before where they have been opened up, you can see they measure approx 1.0" - 1-1/16".

So my choke reduces the ID size of that transition, from 1.400"ID down to 1.0" id, to speed up the air/fuel charge speed.

When I did rev.2 with No chokes and 1-3/8"ID tubing, the charge speed, seemed to be the cause of the bike falling on it's face, from a dead stop and having some hesitation.

When I did rev.2.2 just adding the chokes it was much better, but still had some hesitation.

Rev.1 did not have any hesitation, the ID on the hose was reduced down to 1.100" ID, but it did not have any chokes, Rev.1 mid range to top end was not as good as Rev.3.

But i noticed some hose collapsing, which may have reduced down My ID even further, and speed up of the charge may have taken place.

I can see how the choke would speed up the air and keep the fuel atomized.

Are these chokes something you make yourself on a lath? or can you buy them? Could the same affect be had by putting an orifice plate at the exit of the plenum, that is a 1.4" OD washer with various sizes of hole sandwiched between the manifold runner and the end of the plenum spigot. That would be much simpler.

Right now REV 3 is unheated right? When I ordered my carb. from Tom Langdon he really stressed the need for lots of heat on the plenum and runners in order to keep the fuel atomized. Perhaps if you had lots of heat applied you wouldn't need the chokes.

Maybe, with no heat and no chokes, it is like an engine that is not warmed up, that is, hesitation and flat spots.

Brian

 

[westgl]

Rev.3

Ride Report,

A couple of things happened after the first ride report, and into the second ride, I noticed that the trans was shifting very poorly.

trans was acting up, and shifting was not very smooth like it had been.

I was thinking this could not be the intake, could it, take from a stop and the trans shifting weird, couldn't be.

Even with Rev.2 Take off from a stop was kinda funny, not quite right.

So I remembered i had done a Engine flush with 1/2 quart of ATF in the engine, even the engine was not very smooth like it was.

I drained & chained the oil, slapped on a new oil filter.

When i was draining the oil I was noticing How Dark Black the oil was, with only 300 miles on the oil change.

I shined a light on the oil while it was draining, I could not see light through the oil. The Oil was black as coal.

Remember, I bought this bike for $400.00, with a frozen motor, it had blown both head gaskets, which means they overheated the engine.

i also had to clean out the cooling lines in the engine as another sign of over heating the engine, oil/coolant mixing due to head gasket failure, the cooling line had a thick tar sutance of solidified oil in the coolant lines from teh top of the engine down to the front of the trans cover.

Just like Dan had on his 83' GL1100, thanks Dan for that tutorial of how to clean those coolant lines

I started the engine after the oil change engine was super smooth.

Took bike out for a ride I immediately noticed that it would take off from a dead stop much better, and the trans shifted very smooth again like it used to.

The engine power was very smooth, and acceleration was better than before, and Very smoooooth!!.

The Rev.3 pulls good from 2k rpm up to redline.

But!, Once the engine hits 3k rpm, the bike jumps forward, you can tell where the cams starts to make power.

The bike is Fast!!!!

I am completely satisfied with the low end, Mid range and upper Power and Torque.

My bike pulls from 2k rpm in 4th gear like it did with rev.1, Torque is really good.

Power with Rev.3, is more than enough, every where in the power band, It is fun to ride, exhilarating, a great cruiser, commuter, City bike, Hot Rod!!! :mrgreen: .

If someone would have told me before i had started doing the Single carb conversion, challenge, that they would ride like this, i would not have believed them, and would have thought it was all a load of B.S.

It is not B.S.

I still dont have a second MPG report to give, and i dont want to even consider the first report.

 

[Steve83]

So far, so good! :clapping: :clapping:

 

[westgl]

Yesterdays ride report was at 59 degrees,

Then a second ride at 72 degrees.

I checked, temp, both times, at start up plenum and runners were cold, after engine was a loud to warm up to operating temp, runners & plenum were at ambient temp.

I rode my NC700x first, it is a torqey 700cc engine that is FI, as it is the absolute smoothest bike I have ever ridden.

Also wanted to see power differences, this is a 700cc bike,

The GL1100, started very good, it had a instant restart.

Power on the GL1100 was considerably more, torque was considerably more.

The GL1100, is very smooth, power deliver is very smooth and strong.

If I were to ride Rev.3 like a OEM 4carb bike, the rev.3 is very powerful, if i were to jump on the Rev.3 not knowing it were a Single carb'd bike, I would probablely notice it has a lot of power and torque, and that it was a very good running bike, with no negatives.

It is a very easy to ride bike, comfortable in it's power transitions.

Making for a smooth ride, that is very enjoy-able

In comparison to my New NC700X.

The Single carb. Conversion, makes riding the GL1100 more like riding a much newer bike.

 

[joedrum]

cool im hoping to get to ride hooch today

 

[westgl]

Ok heating the plenum.

What about a tube in copper or brass, through the plenum, shaped like a "U".

Drill two holes, through the plenum, make sure the tube will be out of the intake inlet path, maybe 1/8"-1/4" tube.

Then coolant ran to them, one from the front of the water pump Like Badorderbob suggested and one at the water knuckle on top of the engine.

I like that Bob has a ball valve, so that the amount of flow can be adjusted or even turned off when it is very hot out,

Or Max. flow when really cold out.

I am just thinking ahead, I may take a ride to test the single carb out when it is 20-30 degrees out, that is about as cold as it gets here.

 

[westgl]

I may look at a Single carb for the Bulldog, my 86' GL1200.

It really runs good even with the oEM four carb rack it runs really well.

a couple of pictures out by the new shop

P1020173

• westgl
• Oct 5, 2013

86' GL1200 in front of the new shop, and car port

P1020172

• westgl
• Oct 5, 2013

86' GL1200 in front of the new shop, and car port

P1020174

• westgl
• Oct 5, 2013

86' GL1200 in front of the new shop, and car port

P1020175

• westgl
• Oct 5, 2013

86' GL1200 in front of the new shop, and car port

P1020176

• westgl
• Oct 5, 2013

86' GL1200 in front of the new shop, and car port

 

[slabghost]

Yep looks like a bulldawg ta me. I'll be trying out a vw type 1 intake and carb on my 84 standard as soon as work ,weather and life allow me time.

 

[westgl]

Nice Slabghost,

I look forward to your posts.

slabghost » Sat Oct 05, 2013 6:39 pm[/url]":1f69wqrs]
Yep looks like a bulldawg ta me. I'll be trying out a vw type 1 intake and carb on my 84 standard as soon as work ,weather and life allow me time.

 

[joedrum]

that is nice ..... westgl love the look

 

[badorderbob]

westgl » Sat Oct 05, 2013 9:17 pm[/url]":b8t8d8oe]
Ok heating the plenum.

What about a tube in copper or brass, through the plenum, shaped like a "U".

Drill two holes, through the plenum, make sure the tube will be out of the intake inlet path, maybe 1/8"-1/4" tube.

Then coolant ran to them, one from the front of the water pump Like Badorderbob suggested and one at the water knuckle on top of the engine.I am just thinking ahead, I may take a ride to test the single carb out when it is 20-30 degrees out, that is about as cold as it gets here.

I like that Bob has a ball valve, so that the amount of flow can be adjusted or even turned off when it is very hot out,

Or Max. flow when really cold out. Hay West, at one time I tried running 1/8 copper tubbing, even on the runners underneath, but the problem with a long run will be hotter in on location and cooler in another. I'm thinking with a short run, it might work. Where I got the most heat was to pool the coolant in a chamber and it gets so HOT I cann't keep my hand on it. I know it might be a challege so good luck :thank_you: !! Bob

 

[joedrum]

well went for test ride again today ....to try and figure what I want to do ...on my carb im one turn out on mix screw ....im idling about 1100rpm ....throttle twist is instant and quick ....

no bogging of any kind ....acceleration on road is strong get to 60 quick

on the highway getting to 70 is child's play except for rider

so getting to 100 seems no problem ....except for rider

its for sure way fast ....so I was quite pleased ....

so ive been thing on the grab rail runners witch I think is a very good way to go.....

I found on web a 16 grab bar with more angled shape than a 90 degree more like 45 .....

its also 1 1/4 OD..... this should work well with those orange rubber fasteners that come with type plenum ....

sheesh I wish I had four ....but this sould all hook up as intended and easy to seal

and the head sould fasten as the rest of the grab bar will ...this is the exposed screw kind and I think how ever there fasten on head its plenty good enough to seal ...so for tha moment this is where im leaning ....time to finish this out bike is running great ...
:builder: :mrgreen:

 

[westgl]

That sounds Great Joe,

I would like to see those other grab rails you found that have a less of a bend to them.

My seals for my VW plenum came in Black, so you can get them in either Black or Orange.

 

[82a]

there was question of how to post vids, many use u-tube, another way is dropbox
https://www.dropbox.com/home

 

[joedrum]

ok west ill try
https://www.soymedical.com/du521-1530-06 ... lNKAXHn-tV

yes need to get some vids up things are getting hot in this deal