Inlet Manifold Design - Triple Injectors
Turbo Mini Forums

There must be something to it though... so many of the high end / performance manufacturers do it.

I think that the valve overlap makes the volumetric flow rate higher pro-rata where the flows are all combined - not by much, and that's why the tapers on all the pictures you see are of the order of 5:4 (using the 5 cylinder example) and not 5:1

I'd seen so many pictures like the Audi ones I did try to replicate it myself last year



but gave up as I couldn't cut the aluminium tube accurately along such a length (nor spread it enough at te "thin" end to match the fixed width box).

Schrödinger's cat - so which one am I ???

Well, this is the latest Ferrari F430 engine and a printout from their CFD analysis of the plenum (thanks to robert):





This CFD analysis is showing the nearest cylinder pulling a decent pressure drop so I'm assuming that they have carried out a full transient analysis. When I first saw this I was not that impressed, but having learnt a lot over the last couple of weeks, I reckon they have got this sussed.

There is a slight drop is area along the length of the plenum. This could well be due to the fact that with a high overlap cam, the plenum is feeding two cylinders at a time.

I'd back a modern Ferrari rather than an Audi any day.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Schrödinger's cat - so which one am I ???

On 14th Jun, 2010 Rod S said:

Didn't Audi just take the top three places at LeMans the other day

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Looks like Audi may have droped the idea as well:

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

What the hell are Peugeot doing:

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

On 14th Jun, 2010 Paul S said:
Yesterday, but they don't count as they were diesels

Schrödinger's cat - so which one am I ???

std 998 A+, g295, MD266, RHF4, 109hp @0.8bar/5400rpm

On 13th Jun, 2010 mini13 said:
Oh man, that's quality!

interesting site too, just spotted this, audi only injects on 1 of the 3 intake valves.

std 998 A+, g295, MD266, RHF4, 109hp @0.8bar/5400rpm

On 14th Jun, 2010 Paul S said:
Well, this is the latest Ferrari F430 engine and a printout from their CFD analysis of the plenum (thanks to robert):

std 998 A+, g295, MD266, RHF4, 109hp @0.8bar/5400rpm

It wasnt so much the taper I was referring to.

More the actual method of feeding the main plenum from the slot from a seperate tube.

Clearly there must be some reason for this approach.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Have you thought about using honeycomb to smooth the flow:

MMM Honeycomb. sugar rush!!

MMM lesbians!!

1972 998 TURBO SLEEPER

std 998 A+, g295, MD266, RHF4, 109hp @0.8bar/5400rpm

wow ive never really thought about manifolds so much before...

seems ill have to do much much more research before thinking about buying / fabricating parts for my turbo build

Finally developed my balls sufficiently to attempt welding the plenum and super long runners up:



I'm quite pleased with the end result as this is my first aluminium welding job of any size.

Can't do a picture of in on the car as it is out of sight

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Looks good looks like a moonshine distillery

Looks great Paul, nicely done

1972 998 TURBO SLEEPER

How big is that paul? looks like around 150mm dia from the photos?

It's 4" aluminium pipe.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Nice work:)
Reminds me a bit of this one I saw at IMM last year (is the owner on this forum btw?). Sorry for the bad angle, but the overal shape of the inlet seems comparable. Not a clue where he left the injectors tho.

Attachments:

215.33kb

1963 Cooper
1975 Pick Up

This is a bit different. I don't think that we will be able to fit wipers now :)

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

See, Ally's easy!

just dont dip the tip!