Why has nobody ever developed a ram air system for a mini

It seems a bit strange that we have backward facing carbs in a hot engine bay when a bonnet scoop or a behind the radiator air collection and delivery system could deliver cooler air at higher pressure directly to the carbs.

Must be a reason

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Regards,

Mike
"He who dies with the most toys wins."

Minispeed germany once sold a RIS (Ram Induction System).
http://www.mini-mayfair.net/temp/ram.pdf

I've been told it worked realy well. Consited of a cast plenum chamber and a pipe to the front with a big air filter.

This RIS is actually a re-designed, improved copy of a system sold by K&N untill the early 80s. But I guess it was never very popular since it was expensive.

Cheers,
Jan

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No speakers, no bodykits, no six-inch spacers, no spak filler, no bullshit

There is no need, the air pressure coming in through the front grill forces cool air into the carbs anyway. It comes in through the front and gets forced out the side radiator and down the back of the motor and under the car again.

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

Interesting fact for you mstmini... you might already know... The first prototype minis had the engine mounted the other way round with the carbs at the front... Reason they turned it around is cos the carbies kept icing up....

But its a cool Idea though, it does still get pretty warm in the engine bay, especially with the carby sitting right ove the top of the exhaust (and you know hot air rising).... Maybe you could dream up a crazy solution and post a pic with your invetion in the "crazy backyard s**** that should work... but did" thread (sorry guys, I had to put a plug in there for my thread )

The K&N one that Ashphalt mentioned was pulled from production (as I uderstand it) because it was too efficient (basically).... The piston in the carby was rising faster than the rate of acceleration so you couldn't get the full effect until the speed of the motor caught up to it,,,, , Don't know if I wrote that in a way that made sence... I think you could cure it with a heavier spring or heavier oil... Don't know.. Someone who will remain nameless will probably come on and correct me now ... But at least you will know the whole story

So maybe you could come up with something

Actually when you read a bit deeper into the engine turning around stage of design most of the people involved have admitted it was for the improved gear train in the drop gears as a single drop gear was failing . According to Garfield's book I'm reading at the moment they didn't encounter carb icing up until they turned the engine around .

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Oh ok,, Cool,,, I just heard what I wrote In the "John Cooper" DVD or "The best of the Origianl Mini" but that could be the case. They do still ice over the way they are (I'm told) in their current position... It just seemed relivant.... Have you read yet that they got better mpg with it the way they had it first? Kinda funny hey

So mstmini,,,, How's that prototype coming along?

The carby ice story was a deliberate "myth" to hide the gearbox problems that came from using existing gearbox internals with two heavy primary gears acting as extra flywheels.
The motoring media knew that the prototypes had the carby at the front and then suddenly they had the carby at the back. The media needed to know why they changed the whole layout so they came up with a cover story!

The Austin Maestro/Montego has the carby at the front of the engine bay on an A-series engine.

I think the idea is more to have a resonating pressure wave (due to the lenght of the pipe) which sort of acts like a 'charger' (air gets 'rammed' in the intake).

And of course, like Phat Kat mentioned, it's not a 'bolt on' thing...

Warm air heating up the carb/air 'round the carb is realy only a problem in slow city traffic conditions or standstill. I guess at 20km/h+ it's irrelevant

What I'm going to experiment with is a fixed jet for HIF carbs. 'Cause I have a feeling that under said conditions my mixture weakens considerably due to heat rising from the LCB.

Cheers,
Jan

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No speakers, no bodykits, no six-inch spacers, no spak filler, no bullshit

Vizard devoted most of a chapter to it and came to the conclusion ram charging is pretty much a waste of time. In an A series with only 2 intake ports.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

"Ramming" air into a carby is never really a "Perfect" thing,,, Carbys find it difficult to "feel" a "denser" mixture & it`s difficult to meter the fuel correctly for any given rev because in first gear you are only travelling fairly slow (compared to top gear) & yet the engine needs to be able to go from low revs , rght through to high revs, with very little ram effect,,,, but then in top gear, you have a fair bit of ram effect & you can still find the need to drive from the same low revs right through to high revs in top gear "With" that ram effect most of the way

so,,, how does the carby differenciate (or know) between low "speed" (no or low ram effect) to high speed (high ram effect)???,,, answer is---> it doesn`t do it very well at all

well the only way is to "TRY" to have a "Balanced" system--> float bowl also rammed much like a "Blow-through" turbo system & a restriction just prior to the mouth oif tha carb to "Try" to achieve some sort of depression relationship,,, but it`s not a very successfull solution

However---> most of the later motorbike carbs have a fairly good "Ram-Air" system but they use some pretty wicked carby designs to achieve it,,, if you chose basically any of those late "Ram-Air" bike carbs then you could do it pretty well these days, but i still think it`s a fair bit of mucking around for very little improvement,,, that is unless you like having fun mucking around trying new things like ram air quad bike carbs on twin cam 16v cyl head conversions

but i don`t know who`d want to bother with such rubbish ideas like that tho

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

They had more power as well with the motor around the other way , the extra gear before the gearbox robbed that little bit more which was enlarged as a percentage once the drive had gone through the gearbox .

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the miglia racers run a custom airbox and pipe which creates a ram air effect i beleive. But then they are running injection rather than carbs, so the above problems mentioned are not relevant if im correct?

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Used to have 2000 Cooper Classic Sport 500, No 338, currently miniless

One reason for that is the original was a 948, not 848.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Already designed a cool air box system:

- Two scoops behind grill
- Left and right 3" flexible pipes to carbys
- Carby box that feeds them cool air (cool air = less volume = more oxgen per unit volume)

Post pictures as soon as all constructed.

God...I've gotta get a life!

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Regards,

Mike
"He who dies with the most toys wins."

Interesting reading here I can't believe the marketing department lied to us

So with the benefit of 50 years - and advancements in engineering and materials - has anyone found a way to improve the gearbox design and rotate the A-series back to its original orientation, in a Mini?

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