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Charlie,Quote:
Originally Posted by mrcrsr
Looks like some back wards throttle fabrication is gonna be needed (maybe), can't really tell what options are available from the one-side photo or if it's possible to put the linkage on the Merc side without having it operate back wards ????
Whats the measurements on the ports, ID, OD Wall thickness and how long can the stacks be before theres interference with the cowl ???
No, its the right way. The mercs are backasswards :D
Just switch the cable to the OMC position on the hot foot :thumbsup:
Good come back............LOL ......:reddevil::DQuote:
Originally Posted by baja200merk
i have an in control foot throttle so i don't think the cable travel is reversible(uses a flex type(think 10 speed) multi strand wire cable in a normal teleflex jacket). it'd be easy enough to fix, after all this fabrication the easy part will be to build(or modify) a throttle arm that outputs above the pivot point instead of below to reverse the travel, as well as building a bellcrank like the old bridgeports had. gary, i'll have to measure the od of the tubes where the butterflies are. was going to trim them down, install velocity stacks and then blend everything so its nice, and enlarge the inner bore as much as possible up to the butterfly. this intake should at least give evn airflow to all the cylinders. kevin, do you have any pics of the linkage design on an engine?
Charlie,
As for the velocity stacks and sizing, there are allot of stacks available for Harley's and all other bikes that I think would do the trick, just go to Ebay and motorcycle parts then type in Velocity Stacks, lots to choose from, billet, spun aluminum etc..... Worst case a little spin in the lathe and you'd have some that would fit:
http://www.ebay.com/sch/i.html?_odkw...0063&_from=R40
I've got to tear down my lathe, burned up a bearing in it, what a dirty job this is...............
Not so sure if I can go with the concept that "wall area" of multiple entrys impedes total air flow as much as the stacking effect of poor entry/exit designs, shafts, blades and screw heads have on smaller, higher velocity bores.
Having built many sheetmetal intake manifold's ... err .. looking at this speaker you will see a flat arbor with a raised, large radius "entry" . Were it a throttle bore, the proper exit would be a bore that extends just below the mounting plate and no more than a 7* exit taper no longer than 10% of the bore size, to "shear" the air as it leaves the bore.
Merc did a good job size wise with the down draft plenum. A good rule of thumb is to have the same area as the engines displacment. Round it off and call it 4x4x13=208 cubic inch's ... keeping in mind that "only" one reed block is active at a time, there is more than enough reserve air to pull a charge from , with thottle bore size having little to do with output.
It is real easy to go the other way and get to big on the bore. Open the throttle "half way" and the motor "thinks" it is seeing a properly sized throttle plate. Leaves little room for part throttle opperation.
http://www.mkcinternational.com/imag...rtsnip_280.jpg
Chaz,
Sorry I kept missin' ya on the phone but I think I got it fixed up.
As far as this project goes, this is for fluid, but MAY apply to air as well, read this, especially #2
http://www.pacificpumpandpower.com/d...Loss_Table.pdf
Yep, you are right on track but the friction looses of air would be different. FWIW, In physics, fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow—the natural science of fluids (liquids and gases) in motion.
Rick , I read the problems you were having. Saw some good info and some .. well we havent spoken in a while, so I rang ya up ... ;)
Water is just thick air, so all rules apply. My point being, as they express it in their charts. That they measure losses in HUNDREDS of feet of pipe. As well as those of just single fittings.
You can throw that orifice (throttle bore) on the bench and get a base line.
Now take another section of tube the same length, tape or glue it on and pull it again. You might see a 5 or 10 cfm loss.
Take the throttle blade out and youll see at least a 50 cfm gain .. pull the shaft out and pick up about the same. Now some of that is related to friction, but from what I've seen, it has to do with the column being disrupted and part of it tumbling.
That 3 hole JohnRude body puts one hole over a closely linked pair of reed block entries. It also flairs out on the exit pretty early.
The only real down side is that it needs more plenum volume and the std air flow picker uppers. Well the bellcrank thing too , but thats not to hateful.
My motors are getting the Merc plenums with some warmed over stock bodies. Maybe sometime in the future I might make a couple of billet rail sheet metal intakes with two propper size holes out the front.
Gotcha Chaz, thanks for the offer, still may ring ya back if this doesnt work. All I know is what I(but then again that was water under pressure) was taught like 20 years ago in fire school, a 6" diameter hose carries way more than 3-2" diameter hoses. Not to mention the friction, and length, but runner length is not really a big deal here. Either way, I can also see where too much could be overkill. I dont know motors much anyhow, I can turn a wrench, but not much about the science behind what works like others who have dealt with this stuff much longer than me.Quote:
Originally Posted by Chaz
Come on charlie, a mercruiser shift cable doohickey and your set :D :DQuote:
Originally Posted by mrcrsr
thanks for the input gary, i'll take a look on fleabay! thanks for the input as well charly, i was thinking the addition of the .675" thick reed plate would help add to the plenum volume, as well as adapt my bolt pattern. the linkage is the least of my problems, lol! kevin, do you have any pics of the front of the etec where the linkages are? i'll start on this project soon, got a couple of more engines that need to go out from being rebuilt before i make a mess of my shop again w/ aluminum filings everywhere
it'll look better out of a piece of machined alloy,lol! wouldn't want to make it too easy, what fun would that be??Quote:
Originally Posted by baja200merk
Quote:
Originally Posted by mrcrsr
:iagree:,.....LOL, if it was easy then everybody would have one, no fun there........:D
wat i took out of the bell mouth document
was that the ideal would be an elliptical shape for ultimate performance
but that it was not as important, as according to the researcher conclusions
even a small radius already performs well in keeping laminar flow and high flow velocity
it might be an idea to create the largest plenum ( intake spacer with common room ) possible
while maintaining a good fit under the cowling
http://papers.sae.org/2008-01-3007/