Topic: Hondaman gave me an idea... Velocipods(c)(tm)?

[mlinder]

If you connect the stacks with hollow tubes, that will equalize it as well. As for pressurising it I am not sure that you can make enough pressure in the small space without a turbo on it. At least not without other modifications to the layout of the bike. You could swap in a smaller oil tank and relocate it thus freeing more space. Another concern is air temp. You want cool air,not air off the engine. Otherwise you will not gain much  since warm air is not as dense. Now maybe you could extend the stacks into the open space and have them terminate into an airbox that could maybe be hidden  by the sidecovers?

Connecting velocity stacks will interrupt smooth airflow, and stacks 2 and 3 would have 2 inlet connectors while 1 and 4 would have only 1 each.

You'd be surprised at how much air you can shove in somewhere at 100 mph and it's guaranteed to be more charged than the vacuum created by a stock airbox, or pods, or naked velocity stacks.

I like the idea of moving the charging system to occupy the spaces where the sidecovers are at though. Move battery, electronics, and oil tank to other locations... you could get some pretty large intakes to fit there. Only trouble is the rather quick change in direction of air... however, this could be a good way to help keep condensation from the air entering the airbox. No need to extend the stacks, just route the charging system to enter the airbox from the rear, and keep the airbox up underneath the tank (in stock position, basically).

[TwoTired]

Ram air has been discussed in the forum before.  The problem is, you can't just pressurize the carb throats, as that would actually blow air backwards through the fuel jets or at least impede the fuel flow when ram air pressure is attained.  You would have to pressurize the entire carb or at least the vents that go to each carb, too.  Then the fuel tank would need ram air pressure as well, in order to keep the gravity feed fuel flow in proper proportion flowing into the carbs.

FYI

Cheers,

[mlinder]

Right, I was trying to figure out how to get around the fact that unless I also pressurised the overflow, I'd have some issues. But presurising the overflow has it's own caveats, such as, if a float bowl sticks, and the fuel has nowhere to go, it'll just pool in the cylinder. Which isn't good.
I'm sure I could pressurise the tank and carbs, but getting a good even balance could prove to be very difficult.

[mlinder]

Or could just cheese out and do something like:



No equalisation, but good flow and filtration. Ugly as sin though.

[fuzzybutt]

i had a datsun 240z years ago in florida, had the triple webers on it and around the carb mounted stacks were rubber rings that pod filters would clamp on to.

[antiq]

If velocity stacks are to be used. The single best way I can see is to have them extend into the stock airbox. It is a tradeoff over max power but should provide an increase in power as long as the stacks fit smoothly with the carbs. The airbox will provide good filtration and even airflow to all carbs. Enlarging the inlet to the airbox with an airscoop of sorts can add a small bit of pressurization. This and some tuning of carbs and possibly rejetting can give a noticeable improvement in performance. I'm not an engineer but I believe this can work and if someone can provide the pieces to try it I would.

[eldar]

Well if the tubes are used further back then the flow should smooth out. What I wonder is this. Supposedly the air flow needs to be smooth going into the carbs yet is supposed to swirl to allow complete mixing of the air/fuel. It strikes me that this is impossible to accomplish given the small space we have to work with. I also wonder if smooth airflow is that important or if it is more important to have adequate air flow available.

Others here have gotten stacks to work fine and in some case have only put on minor baffling to cut out the initial turbulence from the stack openings.  It seems that the biggest issue stack users run into is trying to equalize flow between the carbs, which probably affects tuning more than all but the worst turbulence. this equalization would be solved by either using a main box such as the stock boxor by using tubes placed at some point between the stacks. So what you really have to figure out is if you want form or function.  If it is form, then use tubes as they will be pretty hard to see, if you want function, use an airbox but then at that rate you may as well just modify the stock box somehow.

You seem to want both so you will have to make concessions. Which I think would be to use a single filter unit that fits over the openings and then about 1 - 2 inches use equalizing tubes because I doubt they will mess up air flow any more than if you did not use them. This is not a super high flow system so I doubt super smooth air is that critical. It is a 70s carb set up which is less than perfect as you already have to deal with 4 separate carbs, each with its own quirks. So ultimately you should rule out anything when experimenting.  I actually feel like experimenting with something like this too. To bad for me is that riding season is almost done so what is left will be spent riding!

What ever you try, good luck on it.

[HITMAN]

If you could make it, I might buy it with one exception...   Brass screens!!!

I have been contemplating a purchase from this company http://www.velocity-of-sound.com/ but it's borderline cost prohibitive.

[mlinder]

Final design.
Quite simple, and undoubtedly the best.

Gonna make one. This is simplified, there will need to be stops and such to hold things where they are supposed to be.

[DarkRider]

Very nice looking design man..Me thinks im gonna be paying attention to this project of yours...I can already think of one bike i would like to use something like this on...Are you making them for specific applications or are you considering being able to make them to suit different applications if you were to sell them?

[mlinder]

Very nice looking design man..Me thinks im gonna be paying attention to this project of yours...I can already think of one bike i would like to use something like this on...Are you making them for specific applications or are you considering being able to make them to suit different applications if you were to sell them?

Since the distance between stacks would be different from bike to bike, at the very least, each front plate would have to be different from model to model.
The rest could, conceivably, be the same.
We'll see how it works on my 750 first

[DarkRider]

as said.. i will be keepin tabs on this..