Turbo plenum design

[pork]

I built first one without taking into account any consideration of air flow, more I think about it there isn't gunna much chance of even distribution of air between the cylinders

Iv been reading about twin plenums, small pipe and larger pipe joined together with a slit between them feeding the air, apparently this aids better air distribution.

There's a lot of info on lots of forums but a lot of it contradicts each others comments, so totally lost

Old design

Can anyone point me in the right direction

 

[karlj]

I would put the inlet in the middle

 

[pork]

A lot off designs are fed from the side, but then taper down to the furthest cylinder

 

[karlj]

Before messing with different designs, get it working and then refine it.

If there's loads of contradicting information out there go with what works for you and the MA

sorry if it sounds arsey

 

[frank]

A lot off designs are fed from the side, but then taper down to the furthest cylinder

mine did eh neil

 

[pork]

Before messing with different designs, get it working and then refine it.

If there's loads of contradicting information out there go with what works for you and the MA

sorry if it sounds arsey

Haha, no worries, gotta scrap this plenum, doesn't fit properly without changing other things, that'll teach me for making parts without a car! Been finding this out a lot recently

Oh we'll, never mind, no point worrying bout it, jus gotta do it ay?

Soif iv gotta make another one, I might as well do it right second time round

 

[pork]

mine did eh neil

View attachment 21349View attachment 21350

Haha!!!! You have made everything!!!

So is this the best way to go?

What bout these twin plenum jobbies?

 

[frank]

Haha!!!! You have made everything!!!

So is this the best way to go?

What bout these twin plenum jobbies?

dunno mate, its probably more critical when N/A i guess, where intake airspeed would have more effect on N/A volumetric efficiency surely ?

 

[pork]

What about these? Reckon I could make one, seems to be best way 'apparently'!

Thing is, I can't find any write ups about how to calculate the volume of these

 

[pork]

 

[frank]

i think a lot of designs are just "theory" tbh neil, volumes and tuned lengths only work in a narrow rev-band, most modern factory designs are a basic tubular plenum and very long thin (bunch of banana) runners eh

 

[pork]

most modern factory designs are a basic tubular plenum and very long thin (bunch of banana) runners eh

A ahh, spose they are, never really thought of it like that.

What you think to the previous pics, worth a shot, or not worth bothering? Or jus go for the similar tapered one like yours?

I'm gunna have enough trouble getting fueling balanced as it is, without the added headache off uneven air distribution, so I think a properly designed plenum should help with some of the upcoming issues.........right haha?

 

[frank]

i would stick with the one you have mate, you could do some flow tests with a hair drier and ping-pong balls

 

[pork]

i would stick with the one you have mate, you could do some flow tests with a hair drier and ping-pong balls

Yeah, about that.....I screwed up....again lol, doesn't fit right without changing other things, fits carbs beautifully, but made it without the car, so gunna be easier to change this, rather than get another manifold, or move bonnet catch, or clutch cable, and...........well you get the picture

 

[karlj]

Or those polystyrene balls you get in bean bags

 

[pork]

I jus tried hair dryer, most of the air comes out of the left runner, hardly anything comes from the runner nearest the inet

 

[frank]

I jus tried hair dryer, most of the air comes out of the left runner, hardly anything comes from the runner nearest the inet

you could fit reducers inside the tubes to equalize the flow eh neil

 

[pork]

you could fit reducers inside the tubes to equalize the flow eh neil

I suppose, but isn't that a bit counter productive?

I know your right and should jus make do until I know it works then get all anal on proper designs








(haha....anal )

 

[frank]

I suppose, but isn't that a bit counter productive?

)

only if the reducer was smaller then the venturi inside the carb eh (very unlikely )

 

[pork]

Ok, jus ran downstairs ripped out carbs to give this a try...with added help from the misses, not happy bout using her hair dryer tho!

And yes, you are right, it does even out,