Individual TB thoughts... Header syyle intake? Crazy Swedes?
04-02-2005, 09:53 AM
#31
Drifting
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Skunk,
It would be good if you have bigger TB's & build
tapered runners to meet at the entrance of the
port or better still would be to CNC the entrance
of the port area tappering outwards to meet at
the TB just like the M3 carbon intake.
It would be good if you have bigger TB's & build
tapered runners to meet at the entrance of the
port or better still would be to CNC the entrance
of the port area tappering outwards to meet at
the TB just like the M3 carbon intake.
04-02-2005, 11:08 AM
#32
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Originally Posted by J Chen
Skunk,
It would be good if you have bigger TB's & build
tapered runners to meet at the entrance of the
port
It would be good if you have bigger TB's & build
tapered runners to meet at the entrance of the
port
better still would be to CNC the entrance
of the port area tappering out
of the port area tappering out
04-02-2005, 02:43 PM
#34
Burning Brakes
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Originally Posted by J Chen
43mm ID is small NZ.
04-02-2005, 03:04 PM
#35
Drifting
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If you put in the effort to go individual TB's
you might as well do it properly. The purpose
of tapering the runners is to create a venturi
effect whereby the air velocity is increased.
Theres also the benefit of better equalise flow
to each cylinder. Thus, we're not only looking at volume of air flow alone. No point in flowing lots
of air if the velocity is low.
you might as well do it properly. The purpose
of tapering the runners is to create a venturi
effect whereby the air velocity is increased.
Theres also the benefit of better equalise flow
to each cylinder. Thus, we're not only looking at volume of air flow alone. No point in flowing lots
of air if the velocity is low.
04-02-2005, 03:09 PM
#36
Race Director
Thread Starter
J Chen,
It will come down to the TB location, Like other designs, I plan on having the TB located as close as physically possible to the ports. Then I can make the trumpets from there... sound like a solution?
It will come down to the TB location, Like other designs, I plan on having the TB located as close as physically possible to the ports. Then I can make the trumpets from there... sound like a solution?
04-02-2005, 03:34 PM
#37
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Originally Posted by J Chen
Skunk,
I was talking about the taper of about a 1/4 to
1/2 inch at the entrance to the port & not enlarging
the whole port area.
I was talking about the taper of about a 1/4 to
1/2 inch at the entrance to the port & not enlarging
the whole port area.
04-02-2005, 11:37 PM
#40
Drifting
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NZ,
You should mount the TB's as far away from the port
as possible. Close to the port is no good, under partial
throttle conditions, air that is passing through the TB is
very turbulant. What you would want to do is to smooth
out the air flow as much as possible before the air enters
the combustion chambers. Back in the days when we were
fooling around with Weber, Dellorto carbs, we found that
the distance from the butterfly to intake valve was very
important. Get it wrong, you get poor throttle response.
Worse case scenario, under sudden throttle opening, the
engine will bog down & spit fuel back out the trumpet.
You should mount the TB's as far away from the port
as possible. Close to the port is no good, under partial
throttle conditions, air that is passing through the TB is
very turbulant. What you would want to do is to smooth
out the air flow as much as possible before the air enters
the combustion chambers. Back in the days when we were
fooling around with Weber, Dellorto carbs, we found that
the distance from the butterfly to intake valve was very
important. Get it wrong, you get poor throttle response.
Worse case scenario, under sudden throttle opening, the
engine will bog down & spit fuel back out the trumpet.
04-02-2005, 11:54 PM
#42
Drifting
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Nope NZ,
Take a closer look. There is actually a manifold
which is about 3 inch long. The TB mounts to the
manifold before it is mounted to the head. Perhaps
what you saw was only the TB & the plenum chamber.
Take a closer look. There is actually a manifold
which is about 3 inch long. The TB mounts to the
manifold before it is mounted to the head. Perhaps
what you saw was only the TB & the plenum chamber.
04-03-2005, 04:28 AM
#45
Nordschleife Master
J chen>> Yes the M3 intake is a beauty! It's not that expensive, ranging between 1000-1500 EUR depending on options.
NZ>> I just saw a picture of an old Toyota with a header type intake manifold without plenum. But you need plenum volume for high hp applications. Some use a forumula of 1.5 times the displacement to calculate plenum volume. To calculate the runner length you only need to decide at what rpm you want peak torque, then you can calculate the optimal length.
NZ>> I just saw a picture of an old Toyota with a header type intake manifold without plenum. But you need plenum volume for high hp applications. Some use a forumula of 1.5 times the displacement to calculate plenum volume. To calculate the runner length you only need to decide at what rpm you want peak torque, then you can calculate the optimal length.