figured this would be appreciated in here alot. had a buddy let me know cut open and rework his rbc intake manifold for his k20 powered eg. i think it turned out ****** awesome hence the reason for so many pics
















































































mike

 

stellar....
in for the power results.

 

thanks...... dont know if he is dynoing though unfortunately. i told him i would expect gains to be around 10hp at the wheels based on what ive read an how much power he is currently making which 230whp. he did say something about the dynoing but i dont know when he was talking about going.


mike

 

there's a local guy that had his rbc manifold ported.

with stock rbc he made 226whp (93oct)
then
when he went back to same dyno to get retuned with the following changes:
bigger injectors, e85, bigger tb, ported rbc manifold he picked up 9whp.

So.... it was kind of hard to really say which factor provided the most gain.

 

Killer work! How much time was in this? Looks great!

 

yes very true..... as for that guys engine...... the power seems a little low for all those mods done from before to after.


mike

 

Looks great, lmk if you want practice doing another (free of course )

 

thanks, right at 10 hours was put into it. this guys got the killer deal because he was the proto, they are always less cause i dont know how much time will go into them. i base my pricing off the proto.


mike

 

Do you have before and after flow numbers?

 

negative... the manifold is back on the car though and the owner is very happy with the butt dyno results. the car did 232 whp (i asked him last night) before the intake porting. i would really like to get it dynoed to see the gains trust me. ill keep bothering him to see if i can make it happen.


mike

 

Cool. I've always wondered if it was possible to grind down the welds to give it a cleaner oem-ish look. I'm thinking about getting my rrc ported but hate the welded look.

 

u could grind them down but i would imagine u would need to burn into the base metal a little more which would cause a depression along the weld line on the inside. dont know if it cause any turbulence or anything but i know i had looked at other manifolds that had be reworked and most all were not hot enough to burn through. mine did in some spots but not in others where the base metal was thicker.


mike

 

Great work as always!
I vote H22 manifold next. You don't even have to cut it open to get at the runner openings. I've seen several guys port these manifolds but only a few make significant power. You do great work, with that said, I think there is a market for ported manifolds.

Nah2b's ported manifold was actually proven to make power.

*Testing performed by HT member's JayWest and TurboGixxer*

Skunk2 manifold(Blue) vs ported stock h22 manifold(Red)

 

damn it did really good compared to the skunk mani..... did it still have the butterflys in it? or is this one of his with the custom upper plenum? i have no problem with porting a new mani, i just need to find somebody that wants to port theirs.


mike

 

No butterflies. .5" spacer was added between the upper plenum and lower half. As a result, power picked up from 240.08/170.89 to 240.70/173.47 and mid-range picked up a little more.

link to test below
https://honda-tech.com/forums/all-motor-naturally-aspirated-44/randy-owens-h-series-intake-manifold-testing-2910347/

 

Were they the white-colored spacers? I saw those on another post.

I'm thinking about having some made to increase the total volume of my NSX intake manifold, and if your were indeed the white ones, I'd like to know where you had them made.

Thanks.

BTW, nice work AMM. It is apparent you are meticulous with your work.

 

It wasn't my R&D, parts or port work.
However, from the pictures below, it looks like the original spacer from the H22 manifold but the butterflies are gutted (not shown) or a machined piece that resembles the original spacer.
I would contact NAH2B or JayWest on here about the spacers. I was just showing the OP some other manifold porting options to consider for I think there is a decent demand for it.

Ignore the other two custom plenums, I'm strictly referring to the stock upper plenum

 

thanks frostwhite, i try to make them as perfect as i can.

as for the h22 manifold, i would need to see one in person to decide what i would want to do with it...... yout know custom plenum or what not.


mike

 

I'll send you a manifold mike ... If I ever find the time to haha

 

u still need to send me a head lol.


mike

 

Mike,

I'm considering one of these grinders for my own home porting projects:


vs.


Any thoughts or suggestions?

TIA!

 

i use all air tools, ive never used electirc tools so i reallly have no suggestions for u but this..... if u get one pay the money and get one that u can adjust the speed on cause u dont want to be turning 20,000 rpm when ur using cartridge rolls.


mike