Inlet upgrade?

Voodooo said:
What gains would be had if the stock air box had holes drilled or cut into it?
or if the bottom and back were cut open and pod filters were used inside. This would keep the original looks.
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Wasn't there a forum member who was thinking alone these lines?
I remember him saying he was building a new airbox that used flat filters along the sides of the box.
It would have louvered side covers (shark gill slits would be cooler) to hold the filters in place, and provide flow into the airbox.
Seemed like a pretty good idea.
1. Much more filter surface area
2. Larger inlet for less restrictive flow into the airbox
3. Eliminating the original internal filter element will create a larger airbox plenum as well
 
TonyA said:
Hi Voodoo , You have a spare air box ? Commando or Domi ? At any rate if you don't mind PM me with what Norton are charging for that , Thanks
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I have the commando. I bought it when Callum was still in parts. Can’t remember what it cost.
 
BritTwit said:
Wasn't there a forum member who was thinking alone these lines?
I remember him saying he was building a new airbox that used flat filters along the sides of the box.
It would have louvered side covers (shark gill slits would be cooler) to hold the filters in place, and provide flow into the airbox.
Seemed like a pretty good idea.
1. Much more filter surface area
2. Larger inlet for less restrictive flow into the airbox
3. Eliminating the original internal filter element will create a larger airbox plenum as well
Click to expand...
I’m not aware of that being said before. I’ll have to look for the thread.
 
TonyA said:
I know what you're thinking ! What did this guy do to his bike !

Inlet upgrade?


This big gap is needed to get the seat on or off and for free breathing .

Inlet upgrade?


And as Free Spirits of Italy says : " All upgrades are easily and fully reverseable "

Inlet upgrade?
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The path forward , more details :

The plumbing and its ugliness: I am running a primary and seconday oil/air separators .

Inlet upgrade?


In this section I will call "Tribute to iwilson" for the small enough to fit air/oil separator : from the Bangood of China Co. Notice there is already 5mm deep water in the glass from just idle and blipping before the test run.

Inlet upgrade?


The large inlet tract showing the step at the throttle body inlet . I will match this with a sanding mop one day :

Inlet upgrade?


The hanger bracket I used is aluminum cut and drilled. The cross straps are steel.

Inlet upgrade?


This section I will title " performance " : This image shows the collection in the bottle so far. This is after only 75 miles BUT I am impressed ! These were high speed runs guys , for the first time I saw 130 MPH indicated and it was EASY ! (Ya hear that Voodoo ? 130 MPH and more left ! ) :) :cool:

Inlet upgrade?


Thanks to Coote's , iwilson , SCS Delta and others for sound advice and encouragement .
 
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Looking good. Like the filters! There has to be at least 2x the filter area of the standard set up.

So, might be a silly question....the air/oil seperator looks like something you’d run on a compressor outlet to get clean moisture/ oil free air. This is connected to the crank case breather, right? I can’t quite see where the hose ends. So the moisture you saw initially....do you think this vapour just boiling off as the oil warms up? Then looks like oil vapour from the crank case, as looks like it’s mixing with the water after your run, giving you the oil/ water emulsion in the catch glass. Is this in the name of seeing what's going on? as you could just vent to air via a filter, correct? I’ve played around with crank case venting on my cars...two crank case vents to an oil separator...just wire mesh...oil vapour condenses on the mesh and drips into a catch can...which also vents to atmosphere via filter. I get oil, but I’ve never looked at any moisture content. I’d be tempted to try something similar...but as you mention, size is a real constraint. I think I’d probably not want to catch the water and avoid the oil/water emulsion clean up from the catch glass.

From your tests, do you think it’s positives throughout the Rev range? I wonder if Norton ever tested/ experimented with airbox volumes..or were they designed for aesthetics and the volume was simply what it was as a result of the design?

Sounds like you are really allowing the engine to breath better from the inlet side with performance gains! Do you think there are any negatives to venting the crank case to atmosphere vs to an airbox, where you’d get positive crank case ventilation? I guess PCV better for emissions. Of course you could connect the vent to the exhaust via a lambda bung if you don’t use them.....think I might want it a bit further down stream..hmm..not sure!

Awesome pioneering work there though! Always find this stuff interesting!
 
Vernon240 said:
Looking good. Like the filters! There has to be at least 2x the filter area of the standard set up.

So, might be a silly question....the air/oil seperator looks like something you’d run on a compressor outlet to get clean moisture/ oil free air. This is connected to the crank case breather, right? I can’t quite see where the hose ends. So the moisture you saw initially....do you think this vapour just boiling off as the oil warms up? Then looks like oil vapour from the crank case, as looks like it’s mixing with the water after your run, giving you the oil/ water emulsion in the catch glass. Is this in the name of seeing what's going on? as you could just vent to air via a filter, correct? I’ve played around with crank case venting on my cars...two crank case vents to an oil separator...just wire mesh...oil vapour condenses on the mesh and drips into a catch can...which also vents to atmosphere via filter. I get oil, but I’ve never looked at any moisture content. I’d be tempted to try something similar...but as you mention, size is a real constraint. I think I’d probably not want to catch the water and avoid the oil/water emulsion clean up from the catch glass.

From your tests, do you think it’s positives throughout the Rev range? I wonder if Norton ever tested/ experimented with airbox volumes..or were they designed for aesthetics and the volume was simply what it was as a result of the design?

Sounds like you are really allowing the engine to breath better from the inlet side with performance gains! Do you think there are any negatives to venting the crank case to atmosphere vs to an airbox, where you’d get positive crank case ventilation? I guess PCV better for emissions. Of course you could connect the vent to the exhaust via a lambda bung if you don’t use them.....think I might want it a bit further down stream..hmm..not sure!

Awesome pioneering work there though! Always find this stuff interesting!
Click to expand...
I doubt Norton did a lot of air box design work . But I really don't know. My bike has oil discharge into the air box and my travels with the Norton need to consider this. Without any air box you must consider what you do with the crankcase vent. I already tried sending it to a small vent filter and that did not work well enough . I still ended up with oil spittle coming out of it. This oil/air separator keeps the oil/water contained until I empty it. Here is the oil/air separator after 350 miles :

Inlet upgrade?
 
TonyA said:
I doubt Norton did a lot of air box design work . But I really don't know. My bike has oil discharge into the air box and my travels with the Norton need to consider this. Without any air box you must consider what you do with the crankcase vent. I already tried sending it to a small vent filter and that did not work well enough . I still ended up with oil spittle coming out of it. This oil/air separator keeps the oil/water contained until I empty it. Here is the oil/air separator after 350 miles :

Inlet upgrade?
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Holy crap. I’m lucky. My commando doesn’t add a drop to the bottle.

my Domi on the other hand does.
 
I think Norton’s airbox design efforts went as far as styling!

To my eye it looks way to small.

But worse is the air feed.

The seat sits tight on the frame, the air intake is right under the seat, I really struggle to see how the air intake to the airbox can get enough air to feed the motor at WOT through the gaps around the seat, airbox and frame....
 
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TonyA said:
I doubt Norton did a lot of air box design work . But I really don't know. My bike has oil discharge into the air box and my travels with the Norton need to consider this. Without any air box you must consider what you do with the crankcase vent. I already tried sending it to a small vent filter and that did not work well enough . I still ended up with oil spittle coming out of it. This oil/air separator keeps the oil/water contained until I empty it. Here is the oil/air separator after 350 miles :

Inlet upgrade?
Click to expand...
Well, you need to do something, that’s for sure. Their seems to be a fair amount of disparity between owners experiences. I’d definitely want to capture it vs it just dripping out of a filter.
 
TonyA said:
I doubt Norton did a lot of air box design work . But I really don't know. My bike has oil discharge into the air box and my travels with the Norton need to consider this. Without any air box you must consider what you do with the crankcase vent. I already tried sending it to a small vent filter and that did not work well enough . I still ended up with oil spittle coming out of it. This oil/air separator keeps the oil/water contained until I empty it. Here is the oil/air separator after 350 miles :

Inlet upgrade?
Click to expand...

So long story short . Is it worth the time to this inlet upgrade ? Hell Yes ! Especially for a track day weekend ! My plug after 350 miles with Delta 400 race cans map :

Inlet upgrade?



This is what it will look like without the side covers : There is still lots of room in there to get creative. Like build a frame off of the rectifier/regulator bolts to house the air temp sensor and a better fit for purpose catch tank. The last shot will be with the side covers fitted and then I will wrap this up.

Inlet upgrade?
 
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Just got a reply from Jenvey ref upgrade to 40mm TBs. and they have said that they can't supply anything to do with Norton direct and suggest I contact them for help, . I'll put that line of enquiry on the back burner.
 
Al's#5 said:
Just got a reply from Jenvey ref upgrade to 40mm TBs. and they have said that they can't supply anything to do with Norton direct and suggest I contact them for help, . I'll put that line of enquiry on the back burner.
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You can have your TB's bored out and larger throttle plates fitted . I don't think you will need to bother with Jenvey if you do this. There are businesses that specialize in throttle body boring . I have seen it advertised for $125 per throat here. It will be crazy expensive to get Jenvey involved with this.
 
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TonyA said:
You can have your TB's bored out and larger throttle plates fitted . I don't think you will need to bother with Jenvey if you do this. There are businesses that specialize in throttle body boring . I have seen it advertised for $125 per throat here. It will be crazy expensive to get Jenvey involved with this.
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Seems the way to go.
Buy a spare set of 961 TBs and hog 'em out.
Maybe have 'em gold anodized too.
Add Tony's air filter mod, and a dyno tune.
You'd have a cool, unique 85-90HP 961.
 
are the throttle bodies even a restriction?
No cams and no tuning is even available for the added air flow and needed fuel

TonyA said:
You can have your TB's bored out and larger throttle plates fitted . I don't think you will need to bother with Jenvey if you do this. There are businesses that specialize in throttle body boring . I have seen it advertised for $125 per throat here. It will be crazy expensive to get Jenvey involved with this.
Click to expand...
 
BritTwit said:
Seems the way to go.
Buy a spare set of 961 TBs and hog 'em out.
Maybe have 'em gold anodized too.
Add Tony's air filter mod, and a dyno tune.
You'd have a cool, unique 85-90HP 961.
Click to expand...
90hp 961...?
Sorry, my mistake I didn’t realise we were talking about superchargers... ;)
 
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