Thread: Lowport o2 induction manifolds...

I do not know all the technical differences, but the ports and angle of the ports on the lowport head are different from the highport. It creates a different tq band, IIRC.



I think like other people said, it is more different than one is better than the other.

I really do not understand the physics of this, its is just what I was told.

I'd be interested to see a bone stock 100K Highport SE-R dyno VS. a stock 100K Lowport SE-R dyno with a highport intake cam installed. My bet is the lowport car has 5whp more.

Low port---127 cfm at 10 inches (11.5 lift)
high port---127 cfm at 10 inches (10.5 lift)
low port--- 120 cfm at 10 inches ( 10.5 lift)
high port---120 cfm at 10 inches (9.5 lift)

ive looked up numerous sites and forum to see if these numbers are pretty much correct and solid and they are.

looking at these numbers you can clearly see that there are differences in the way the heads flow, as the low port heads seem to be about 1mm lift behind the highport.

and the way you can tell this is becuase at 9.5mm of lift the high port is flowing 120cfm

but at 10.5mm lift the low port is just then making 120cfm

at 10.5mm lift the highport is maing 127cfm

at 11.5 the low port is making 127cfm

low port consistantly being 1mm of lift behind the highport.

and if this is true, then that means its not the camshafts in the head, but the port volumes not the lift of the camshafts becuase obviously with those numbers the low port is always being left behind 1mm of lift. so its not the ammount of lift creating more cfm, but the port volume between the low port and high port....at least thats what i got from those numbers and reading up on it

reasoning??

the high port looks like it's venturi'd while the low port runners are straight in, no cone shape.

lol hahahahaha.

short and sweet.

the O2 induction manifolds are truly a piece of art. jon's welds are some of the best i've seen. every manifold has velocity stacks going down from the plenum to the runners. so no, they are not simple to make which is why they cost a lot of money.

i have not dynoed my car yet with the same setup + O2 induction manifold yet but i'm sure it will have gained power. when kojima drove the car, he said the turbo spooled much sooner and throttle response was better. im assuming the turbo spooling much sooner has something to do with the intake manifold producing more flow. and the throttle body COULD be the intake manifold but is MOST LIKELY the N1 throttle body.

but i recommend the O2 induction manifold off the results i've seen for anyone trying to make top power.

old style HP O2 which is what miko may have been testing. you can see where kojima just welded the IACV plate that O2 induction supplied right onto the manifold. jon does not suggest this as it can hurt flow.



new style O2 for my GTIR but same plenum and velocity stacks for all manifolds built now as far as i understand.



notice the adjustable stainless steel throttle cable bracket.



everything is shaped and sculpted to optimize flow.



pre tapped for vacuum and "true boost" readings and iacv hookup, brake booster, etc



not so easy to make anymore eh?



also, not so easy to make.

definitly not easy to make and you have to definitly know your diameters, you cant just go making runners and plenums, there are certain diameters to keep the manifold within.

there is also alot of machining that the new manifolds have that make them more complex

with some measurements it is definitely doable, much easier to do it like the first style though... He made it as smooth and round as possible inside so that the air flows smoothly, and I have a friend that really can weld that good on aluminum...it's amazing. flowbench this flowbench that, as long as that IM is opened up as well as the TB it is going to flow more, simple as that. I swapped TB's on my stock manifold and could tell a difference.

http://www.sr20forum.com/technical-information-library/218349-swapping-highport-u13-tb-lowport-de-tb.html

but there are reasons to do research and devlopments and that is why the first pic looks nothing like the second, becuase they did alot of research and devlopments on the manifold and made alot of changes all changes for the better.

if you can only make the 1st pic manifold than you are not going to see any kinda gains near the 2nd manifold, which my opnion would be completely useless becuase if its no better than the 2nd manifold... then either buy the 2nd manifold, or do some major research and devlopment and engineer a manifold even better than the 2nd o2 manifold (which i think can be done) but would require a TON of money and alot of good ideas to come together and make something that will be superior to the new o2 manifold

Definitely just you

disagree, if you could make the first manifold it would still be a significant gain over stock. and yes the second one is a result of R&D but making the first one would definitely not be useless. That's like saying that brian crower cams are useless because s4's make more power...they're not useless.




and yes...that is beautiful...those runners are beautiful inside...