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Turning vanes in intake ports on cyl head?

Turning vanes in intake ports on cyl head?

Turning vanes in intake ports on cyl head?

Hey all,

I saw an article on autospeed about using turning vanes in a cylinderhead.  Has anyone ever tried this?  I could not find any further information online regarding this concept.

They talked about using 2 little simple curved vanes to help the air make the turn in the intake port, and then a round vane attached to the actual intake valve itself to help the air start turning instead of smacking straight into the back of the valve head.

I took a picture from the article, and added my own homemade view of how I would think it would look from above to help explain it to you.

Thoughts?  Anything to help head flow is good!


Thanks~ Josh

RE: Turning vanes in intake ports on cyl head?

There have been ports in the past that tried to accomplish similar effects, and tulip valves also are designed to help direct the airflow in an orderly manner.

I hate to be the eternal skeptic, but my guess is that a universal-fit contraption such as this would probably be more of an obstruction than anything else, as every head has different needs. For instance, I wouldn't think a perfect circle would be ideal, I would expect (keep in mind that I am by no means an expert head porter, I'm talking out of the wrong hole here) that you would want different geometry on the short side to help make the sharp turn and take advantage or previously unused potential.

RE: Turning vanes in intake ports on cyl head?

I agree with Andy330hp

Many cylinder heads have flow directors built into the port. David Vissard wrote an artical many years ago on using deflectors in the roof of the port to bias flow to the unshrouded side of the valve. These deflectors are normally cast into the original head, or ground in by modifying the vakve guide boss during porting. They are normally a long tapered rib in the roof of the port leading to the valve guide and designed to guide air smoothly around the guide, with more air being directed to the unshrouded side.


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RE: Turning vanes in intake ports on cyl head?

    What we find concurs with what Pat and Andy have said there is no universal vane design that will work on all heads (jump in here any time Larry M)I suspect that the vanes do more to redirect liquid than redirect air or maybe a better way to say that is they change the pressure in that part of the port causing the air to be drawn to a different section Dose that make sense?


RE: Turning vanes in intake ports on cyl head?

Ford race 4 cyl (DBA ??) used a stainless-steel
shroud that you slipped onto the valve stem
in the bowl-area before you final assembly of the head

some racers said it worked and some didn't
no dyno data

it supposedly picked up bottom-end torque
with sacrafice in top-end performance

Vanes on the port floor or short turn are usually
result of flowtesting bare ports "WITHOUT" headers or
intake manifold attached as well ...so what happens
is in a live engine , floor vanes hurt HP / Torque
at high RPM

GM did this with the 1st D-Port BBC heads ,
supposedly all developed on FlowBench , but never
backed-up in dyno test -vs- with or without vane
in exhaust port floor , but at that time ,
it was left in production, ... and ProStock / Comp
used the vane to attach welding to, building the floor
upwards till flat without vane effect, along with
raising roof with or without exhaust port plates !
--so what wound up as a BOO BOO , worked out OK in end.

like GM BBC D-Port , other times vane in port floor
short-turn area picks up the flow on a flow bench,
but its false flow, and the engine was really responding
to increased velocity in that area and not the actual
flow gains.


another example is the NHRA SuperStock Chrysler 318-340-360
engine .... before NHRA let any valve shape be used ,
the stock Chrysler intake valve was a Tulip-design,  
it hurt low to mid-lift flow numbers , but high lift were OK

after NHRA allowed any valve shape , we went to a nail-head
design with backcut angles, low to mid-lift numbers
increased with high lift numbers the same as before with Tulips

on the dyno, the Tulips made torque sooner , come on the cam sooner,

with the nail-head valves, torque began later, but wound up as much
peak torque and with a little more Peak HP , but higher by 200 RPM

Actual DragStrip runs were faster with nail-head after rear gear ratio was increased
to compliment .....than was with Tulip valve head

Sort of what Bill Jenkins was trying to describe in his book
and also what Phillip H . Smith's
"Scientific Design of Intake and Exhaust Systems" =>where when the
intake flow was too good for low RPM airflow demands,
you lost too much ram effect at end of stroke.
You got it back as you reved the engine higher if cam timing was OK

you won't have this effect or problem with EFI
EFI frees up the headporter ...you can make a port too big and
not pay a penalty with EFI


and David Vizard being an Englishman ,
would have been very familiar to Ford's English Race 4 cyl
with shroud insert

Larry Meaux (maxracesoftware@yahoo.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers
Support Israel - Genesis 12:3

RE: Turning vanes in intake ports on cyl head?

i know for a fact late 70's honda XL125's came with a center mounted slipin vane in the intake.was suppose to redirect flow towards the short turn.never noticed a difference with it in or not,but widening the short side would give them a noticeably stronger top end.so yea-there was an application and no,it didn't work.

RE: Turning vanes in intake ports on cyl head?

The 2004 F150 with the 5.4L three valve engine has a similar device installed in the intake manifold to head ports.  It is called a charge air motion device.  Simply a shaft with plates about half the size of the intake runner that cause the tumble effect at lower speeds to increase torque and fuel efficiency.  Probably does slightly reduce high RPM power, but it is a truck application.  Both banks are connected through a single bell crank driven by a servo.  Pretty neat.

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