h224thgensedan

Okay I am in the process of porting out my intake manifold and I have found two designes by two different members. I am wondering which manifold has advantages and disadvantages.

First is Nah2b's manifold


Next is AWOC's manifold

GoldLudeRay

well one will more volume than the other
and one will have shorter runners than the other

basic im theory

Salsa

well AWOC's has shorter runners and alot of volume in the plenum (think edelbrock Victor X HIGH RPM) small TB?

NAH2B...I dunno what Kind of effect the larger area of the port entrances would have but the runners are longer and theres less plenum volume = more midrange power

get 2 stock manifolds (CHEAP)... port both of them... dyno test... get the real answer

wheres donF? lol

h224thgensedan

I have one of the top mount tb setups from dh-racing to give you some more info. I am leaning more toward AWOC's idea but thought i would get some opinions.

adam00

iTrader: (1)

i have an extra h23 intake manifold and im trying to port it to put onto my jdm dohc
f22b would i benefit from either of these designs over stock

sauceja

I am going more nah2b's route only cutting the guts out of the iab plate to use as a spacer and cutting the top half as well to add more volume space.
No proven results yet but should halfass flow like skunk2 manifold????????

But more volume is definately the goal.

teefunk01

check out roskoracing port too

NAH2B

you cant really consider the wider portion "runners". they are more like a transition between the plenum and runners. the runners begin where the "round" portion starts seen better in Awoc's pic. both of these stock manifolds have 7" runners compared to the euro r's 9" runners.

i chose to leave the transitions in my manifold simply because i already have plenty of plenum volume and they help funnel the air into each runner.

here is a completed pic of my current manifold:



link for more info:http: https://honda-tech.com/forums/drag-racing-36/build-thread-import-sports-street-allmotor-h2b-2474967/

as for which is the better lower plenum option for the op, your just gonna have to test each design on your setup.

sauceja

Thats badass. I am living the dividers in because I don't have a machine to remove all of the stuff on the lower manifold.

fast2camciv

should we break these down to street/race/full race? because obviously 1 style will work best on a mid range, street setup...while another style will work best on a full on race setup...

i have a spare manifold im looking to modify, and its a toss up on what to do....

NAH2B

the upper plenum is obviously a race design, but as i said you will have to test each lower half design on your particular setup to see which works best.

sauceja

And that is key because when you start going longer stroke your usable rpm range drops about 700-1000 rpm from where a reg. H likes to rev to. So lower end and midrange power is where I would like to see my biggest gains.

Top end would be nice as well but we are talking around 72-7500 rpm maxish. Since it seems that most but not all cams for the H don't make power a whole lot over 8k rpms its more important to have a steady usable torque curve.

NAH2B

intake and exhaust manifold choice will help to determine where power peaks.

im obviously shooting for mainly peak hp since i will be shifting @ 9500+ rpm

GoldLudeRay

nice high rpm, loving it

sauceja

Whereas my peak will be 7500ish so I hope to have more usable power around 4k-6k prm.

But I am doing it because I have free time and I am bored and I wanted my manifold to hold more volume of air not aluminum.

NA - your car looks good, best of luck to you this year. 10's all the way for you.

DSRxCandyh2bEG

iTrader: (4)

Do the bottum of the manifold like NAH2B's setup and double stack the IAB plates to create more plenum space. Works great... make sure to modify the IAB plates and the upper plenum.

sauceja

Yeah then I will be cutting a hole in my hood for sure if I double stack them. I will have to space my hood more now as it is just using 1 plate. My work so far still unfinished.

Conan the Destroyer

i want to see a video of that throttle body up on the windshield set up.

h224thgensedan

Thats how far I am on mine. Takes for ever with a dremel.

sauceja

Yeah I got a huge compressor and a die grinder. Now that I got a carbide tip though. It hauls ***.

Wish I woulda just bought one from the start. My dad and I were talking about how the air flows into the manifold and where contiplating different characteristics of how the dividers could be cut to maximize flow into the #4 cylinder right after air flows into the manifold.

I taped the gaps in the spacer and jbwelded all to be smooth inside. The top/bottom will be gasketed so not worried about that. I will smooth it back down with a gasket removal pad. The upper plenum had the pcv port removed and welded shut along with all but 3 vacuum ports that I will need. 1 fpr, 1 map, 1 extra for vac. gauge or whatever. oh yeah the brake booster is still there but thats given really.

I still have to port the TB opening but am gonna wait until I have the tb I will use to do that. I am gonna smooth inside the upper plenum more now that I have a bit that works smoother faster.

The lower will get cut more on the dividers to provide a more circular and sharper cut into them and smoothed as far down as I can go.

After that I have some sandpaper wheels?? not like dremel, they have a bunch of "leaves" on them????? will show picture. haha
That should put a lusterous shine and final smoothness to everything.
60 grit to get a better surface and to even out a little more then 80 to smooth.

Tedious work nonetheless. Worth it????? may never know I guess. Fun, Experience, DIY, Learning different skills. DEFINATELY

Will I port a head after this. I highly doubt that one.

h224thgensedan

Mess up a intake manifold 60 bucks. Mess up a head a lot more. Ill allways pay for head work but this is something that is a good experience that is fun.

I am using a carbite to take most of the material away and then finishing with sanding wheels.

ssaccord92

I've got the same design on my car now i've had it for almost 2 yrs. Except i don't have the iab plate me and my friend call it the poor mans euro r. But i'm doing a stroker motor and gonna add the iab plate and i also have 2 port match my TB to 69mm.







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h224thgensedan

Well I got mine to this stage today and then I burned up my dremel. I decided to go with NAH2B's design. Im trying to find a friend that has a dremel so I can get it more uniform.

H23_del_soul

are the H22 and 23 mani's interchangeable/different? what is best if so?

bigsnorlax

no, different bolt patterns.