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Based on that description, George, I've been spoiled by the one-piece 650 airbox.

- Nate >>

On my Dunstall CB 750, I modified the stock air box to house 4 pod filters. I then opened up the bottom/front of the air box to have a sort of ram air effect. It works fine, but I didnt find that it made any noticable power improvements and I dont have a Dyno.
Fish

I'm kind of getting less keen about the RAM idea because of water seepage and the problems that could cause being mounted RIGHT on the front of the bike.

That airbox hose mod with the pool tubing is EXACTLY what I need to do though, if this mystery airbox will even fit into my frame... hmm, may need to do some fabricating.

All the same, I may shelve this manifold/RAM idea for a later date.

I think the 1-4 intake could work, its just like a 4-1 exhaust reversed, if the tubes/pipes(pvc) were the right size, and the "collector" was large enough it should be fine flow wise.
sort of like this crude drawing


Post edited by: 77KZ650, at: 2006/03/17 02:06

RAM air isn't really worth doing at subsonic speeds. The increased drag would probably outweigh any performance gains.

3% HP gain just from routing air from the front of the bike to the airbox. Sounds like a deal to me. If you make 160+ hp from a fairly modern motor, I would think a 3% increase in HP would cost you a whole lot more money in engine work than a RAM air would.

RomSpaceKnight wrote:

3% HP gain just from routing air from the front of the bike to the airbox. Sounds like a deal to me. If you make 160+ hp from a fairly modern motor, I would think a 3% increase in HP would cost you a whole lot more money in engine work than a RAM air would.

I'm going to go out on a limb here, but I'm thinking Kevin Cameron was refering to air pressure gain and not HP. Also, 3% was at 160-170 MPH! 80 MPH yields less than 1%. And of that, engineering can only expect about 75% efficiency.

A turbo charger would be more productive and useful at street speeds, IMHO.

- Nate >>

N0NB wrote:
A turbo charger would be more productive and useful at street speeds, IMHO.

- Nate >>[/quote]

Well certainly.
That involves a disparity in price of easily 1,000 dollars though

I realize I'm a little late for this thread, but I've had a little experience analyzing an intake. I did some CFD analysis on 1-4 intakes like that described above when I was in college, and in all cases the outer cylinders (1&4) were starved of air.

An airbox better regulates the pressure so that all cylinders get the same amount of air, so that its more like the carbs are sucking fresh unaffected air.