Options for RGS carburetor intake manifolds?

[hooksey]

Nice Mr Wolf Man……. Scored last 2, 3rd due in rnd May

 

[murphus]

I have these used 3. There are in good pliable shape. They really didn't need replacement but I replaced them anyway with new ones from Wolfgang last year some time (part of a larger restoration). Are you in the U.S.? The midwest? You are welcome to them. Just let me know what you feel like paying. U.S. only shipping.

View attachment 81550

Missed this 'till now, just pm'd you.

 

[Dellortoman]

https://photos.app.goo.gl/1dACZcyVcJkJ5ckB8

Yep. They're the ones Rob. Nice big round edge on the entry. It's the round edge more than the shape that improves flow.

This widely published diagram (below) goes some way to illustrate what's bad and what's good with velocity stacks. It doesn't cover mesh inlets though. I guess that's because whoever created it didn't think anyone would be dumb enough to fit mesh over a velocity stack.

Will these do, Cam?

Not bad Quentin. At least they have a nicely curved trumpet (as opposed to a conical taper), no sharp edge and no stupid wire strainers. So I'd guess that they would have a positive effect, or at least no negative effect. The only way to know for sure is to flow test them, but I wouldn't lose any sleep worrying about their efficiency if I were you. I'd just worry about dust and grit getting in. Is there space to fit pod filters?

As jheath said above, quite logically, a poorly performing velocity stack will only make a difference when you're looking for the last couple of HP at wide open throttle.

However, I reckon these Dellorto inlet trumpets might start to make their negative effect felt at lower throttle openings. They have everything wrong with them. Not only do the trumpets have a sharp edge and a straight conical taper, but the thick expanded mesh must block off a good percentage of the opening and mangle the air flow into a horrible turbulent mess. Imagine how much worse they'd be with a bit of oily dirt accumulation on the mesh. I reckon if you included them in the chart above, they'd be in the -50% ballpark. You only have to look at them to realise that they fail both as filters and flow enhancers.
They look cool though, which I suspect is their only reason for existence.

 

[piranha-bro2]

Not bad Quentin. At least they have a nicely curved trumpet (as opposed to a conical taper), no sharp edge and no stupid wire strainers. So I'd guess that they would have a positive effect, or at least no negative effect. The only way to know for sure is to flow test them, but I wouldn't lose any sleep worrying about their efficiency if I were you. I'd just worry about dust and grit getting in. Is there space to fit pod filters?


No way I'd use them open. Put quite a bit of effort into enabling the fitment of expansive filters.

 

[Andy]

That exhaust looks seriously cool

 

[piranha-bro2]

That exhaust looks seriously cool

Cheers. Didn't make it to look cool but it does indeed. Put a lot of work into it. Made from segments. A test bed of some exhaust theory (black science that! Ask Red how many hours of dyno time went into the Mule's funky mega!). I downsized the headers slightly from std from port to the X to increase gas velocity. The headers expand after that X and then taper out from there at a given mm/m and continue tapering out through the internal baffle in my handmade mufflers - I think it starts at 38 or 39mm ID and ends at 55mm ID at the end of the muffler. Whether it'll work with the SFQ motor is yet to be seen. If the X doesn't work with the 270-450 phasing I'll probably go to 2 x separate systems L and R.

 

[helicopterjim]

Cheers. Didn't make it to look cool but it does indeed. Put a lot of work into it. Made from segments. A test bed of some exhaust theory (black science that! Ask Red how many hours of dyno time went into the Mule's funky mega!). I downsized the headers slightly from std from port to the X to increase gas velocity. The headers expand after that X and then taper out from there at a given mm/m and continue tapering out through the internal baffle in my handmade mufflers - I think it starts at 38 or 39mm ID and ends at 55mm ID at the end of the muffler. Whether it'll work with the SFQ motor is yet to be seen. If the X doesn't work with the 270-450 phasing I'll probably go to 2 x separate systems L and R.

Lots of early Ducati folk found that a 2 into 1 on a 900SS was okay for midrange and 2 separate with no crossover was best for top power. Not sure how you would get an X pipe on an Ltwin so likely irrelevant for you.

Jim