Just curious how much of a power diffrence would their be between the to. Has anyone done a dyno comparison . thanks

 

I remember I was reading a thread by tbone that was flowbenching the 2 with the ITB's flowing better. But over the stock manifold, the AIR improved it a good deal.

 

ENDYN Claims better flow over ITB's with their ported Skunk2 Manifolds.
I should hope that the AIR Manifold would be better than that......

Note: I would have to see the Ported Skunk2 perform to believe this statement.



Quote from http://www.theoldone.com

"With the plenum side in place and a 64mm throttle body, this manifold will out-flow the best individual throttle body combination we've ever tested. At .500" valve lift the head/manifold combination will flow 349cfm @ 28"H20 with equally impressive mid-lift numbers."

 

its debateable but dont sleep on the AIR manifold ... it does work incredibly.

greg

 

Here you go:



*This is the best i can do with the dyno graphs. The first graph is the comparision between the M22 vs Pro1's that i had posted a few weeks ago. I took off my TWM 52mm itb's, and replaced them with an AIR manifold, 70-68mm RPM service TB, and Velocity stack intake. Nothing else was changed. The first graph with the dotted horsepower/torque lines represents my engine using the TWM 52mm itbs and the Rocket M22 cams. The second dyno graph is my engine with the Rocket m22's and the AIR manifold set-up. Both set-ups were completely tuned with the cam gears, fuel/timing, vtec point etc. I changed the velocity stack intake length numerous times and seeing the results. The length that i used represented the optimal "overall" powerband gain, i.e not gain/losing extreme in different rpms. There was no more power to be found.





The AIR manifold beat the TWM's up top, by 6whp. They only lost 4-5 ft-lbs in certain areas, but gained 4-5 ft-lbs of torque in other areas. That is about what i expected due to resonance characteristics with a plenum based system. I could not overlay the graphs unfortunately due to the original m22 files being moved out of my dynapack software on the dyno PC, and me not being able to retrieve them anywhere. Both graphs are SAE corrected, runs were started at the same coolant temperature (185-195), as well as same intake air temparetures (approximately 50-60 degrees). Just like my other AIR manifold on my turbo hatchback, this manifold doesnt retain a single bit of heat. I had made around 30 dyno pulls adjusting the length of the intake, back to back, as well as tuning and the intake manifold was literally freezing cold to the touch (dyno bay was around 25 degrees). I would rather have a plenum based intake manifold than ITB's anyday due to practicality, drivability and no filtration issues. I noticed just as much throttle response, if not more with the AIR manifold in comparision to the ITB's.

 

very nice comparison

 

thanks alot boosted-hybrid . Where do you mount the iac valve on that manifold just curious i dont see any sensors on it? Do they all run underneath of it

 

wow nice . that AIR cf manifold is no joke.

 

With neptune software i am able to disable the IACV sensor, so i get rid of it altogether. Idle is perfect. I just use the fuel/timing to get it to idle where i desire.

On my turbo hatchback running the AIR manifold, i have the remote mount IACV plate that endyn sells. I was running hondata on that car before neptune came out, so i had no choice. Now that the car is running neptune, i am taking off the IACV altogether.

Here are some more random pics that i snapped of the engine bay:

Velocity stack:



Manifold shot:



*I am loving the s2000 injectors. I picked them up next to nothing, and they are still flowing plenty of fuel for my power level right now.

Firewall/fuel filter shot:



Be prepared to have to move the OEM fuel filter, and notch the supporting bracket for the tps sensor/plug.

 

cool, so endyn will give u that remote iac plate witht he manifold i take it. Also is that velocity stack intake practical for a street driven car being that it dosent have an air filter on it. thanks jeff

 

You have to purchase it from endyn. I believe it was an additional 50.00 for the kit. I not 100% sure on that price though, you would have to inquire with him.

The site that i got that velocity stack from has filters available.

http://www.turbohoses.com/AirRam.htm

I didnt have a filter on it, since the car at this point is just my test mule for the shop.

 

Nice comparison That torque peak is pretty high, rpm wise, what crank are you running? Nice how the torque drops slowly, rather than falling off sharply. And just curious, what throttle cable is that?

 

cool, their is no way to get rid of the evap purge solenoid or the iac valve other than using a ems like neptune right? I currently have hondata so im just curious if removing the evap purge will affect performance at all

 

The specs on the engine are:

86mm bore x 87mm stroke
10.8~11:1 compression (was suppose to be 12.5:1, spotfacing to 86mm killed that)
Portflow ported pr3 head
Rocket m22 cams
Rocket Full valvetrain, Ferrea standard size valves
DTR Fab 2.0 header

The throttle cable is actually the OEM civic one. I made it work with the OEM throttle cable bracket holder in the engine bay.

 

The evap purge you can just unplug, it doesnt throw a code. You can leave the IACV plugged in, but not hooked up to a coolant source with no issues. There is no other eeprom based obd-1 system that know of that can disable the IACV besides neptune.

 

That manifold is beautiful! how much of a loss is there with a filter on the intake? I guess it also determines what kind of filter too but just curious. How much does the AIR manifold run? They don't make one for a sohc do they?

 

yea, how does the the intake piping lenght affect power?

 

With a good filter, there will be no loss of power.

The length of the intake pipe shifts around what is called the resonance point. Resonance is essentially harmonics, or wave travel that is formed. You get high and low points in wave travel, and variation of wave travel speed in a tube. The length of the tube effects the speed of the wave travel, i.e sound and air pressure waves. The speed of the air pressure waves traveling into the intake manifold will vary, as a result of diameter and piping length. The engine creates these pressure waves by the opening and closing of the intake valves in the intake manifold, and the vaccum condition that the engine operates within with a n/a application. The goal is create a "supercharging" or high speed, high point of air wave travel so that more volume or airflow is available inside of the intake manifold when the intake valve opens. Intake manifold has typically two primary resonance points at various rpms points. Typically resonance occurs at two rpms points in the operating rpm range, and its typically double on another, i.e one at 4000 and 8000rpms. There are many different factors that change resonance betweens engines like valve size, engine displacement, cam profile, compression, etc. You can change the resonance points though with the length and diameter of the intake pipe, because at WOT, its essentially adding volume to the plenum/runners of the intake manifold.

 

nice post boosted hybrid! i think that it's possible that the single tb intake manifold you used is well-tuned for the engine it's on, and that the itb's may not be as well tuned.

i am referring to ram-effect resonance, which is a function of total port length(including the velocity stack) and cam timing/duration... because the latter affects the timing of the pressure wave that gets bounced back up the itb.

this is clearly covered, with math and dyno results, check out the 3psi boost in intake pressure@4800 rpm that they documented: http://www.hotrod.com/projectb....html

note that they are tuning for the 3rd harmonic, because that's what's practical with the velocity stack lengths... so the real question here is, are the packaging constraints of the honda engine compartment preventing people from seeing this ram effect? or would you have to use a curved intake manifold that puts the velocity stacks up thru the hood to make 'em fit? if you could run the math on your motor, boosted hybrid, it might be interesting.

i'll cross-post some other info i gathered that is relevant: the reason that the ram-tuned dyno test was so predictable is because pressure waves always travel at the speed of sound... so they can't be affected by taper, port volume, or engine speed.

ideally, there are three pressure waves that have to be tuned for: piston compression stroke, piston exhaust stroke(via cam overlap), and the ram-tuned wave bouncing off of the intake valve closing.

since piston speed causes the air speed thru the port to change, you should tune for that also, after you set up the total intake port length, which includes the stack... i'd guess that you are looking to target the smallest taper and port volume you can get, at the target rpm you set the ram-tune at(??)... because you want the max possible air speed thru the entire port... here you can see how the correct taper should increase the h.p. slightly, albeit on a v-8 motor:

http://www.circletrack.com/139_0302_class/

the ram-tuned port in the dyno test is of course a helmholtz resonator all by itself... the single throttle body plenum manifold used in today's cars should enhance that ram effect if tuned properly, but only at one narrow point in the rpm band, and pretty much only when the 4-cylinder firing order is used... the exhaust system is also a helmholtz resonator that has to be tuned to the specific rpm... 4800 rpm in the case of that v-8 motor?

in my initial post, i couldn't figure out how the ram-tuned dyno test took the camshaft duration into effect... but i think that it all ties together if you read the grape ape "tuned port basics" page: http://www.grapeaperacing.com/...s.pdf

here are a couple of more pages, including some more math: http://www.chrysler300club.com....html
http://www.allpar.com/history/....html

 

Helmholtz resonance phenominon really only helps with steady state (operating at a fixed rpm) equipment such as large scale diesel engines, etc. While you can use resonance points to help enhance certain rpm ranges in the powerband, on a whole it comes to increasing airflow within the IM. As a result its within the runner shape, plenum shape and overall flow capacity of the intake manifold. From what i found designing my intake manifold my senior year based around Helmholtz modeling equations from several SAE articles, its predictable typically only within a given window of rpm points. While my IM made huge improvements everywhere in the rpm range over the edelbrock, it was largely as a result of manifold volume, and runner taper (with 1.35" raised/machined bell mouths on the plenum floor) and not to the resonance of the IM. I was able to accurately predict within 5% of my tuning rpm points with my modeling equations though. The key to a good manifold design is to have the volume of the IM a little larger than the displacement (volume) of the engine, as well as keeping the particle speed high within the plenum through plenum taper, and runner taper. Both have a point of diminishing returns, and calculating that point is the hardest thing to predict. The AIR has worked amazingly well on both my FI and N/a cars, and the displacement, compression and cam profiles are drastically different therefore killing the helmholtz predictability between each application.

 

i think that the place where the ram tuning will help is in drag racing... every time that you shift gears, and pass thru the ram point, you are adding a shot of air that should show up on your e.t. slip... although it'll probably be pretty small overall, those little things are what makes winners in the all-motor classes.

you would of course have calculated the resonance of the exhaust header to complement the intake manifold ram effect, and you'd also have both resonances engineered to work at the optimal peak power point in the rpm band... it all has to work together, and the average joe can't do that with the a.i.r. manifold, for the reasons you just outlined... it's a one-size-fits-all solution that can't be optimal for every motor that it gets bolted to.

that intake manifold project you worked on in college sounds pretty interesting... can you imagine how difficult it must be for car manufacturers to calc and test the helmholtz resonances for stuff like that?

i can't make much out of the dyno graphs because they have different scaling and aren't together... if you had seperate graphs at the same scale, you could probably use photoshop to cut the background out of one of 'em, and then overlay it against the other.

 

The IM that i made was engineered around the primary and secondary resonance frequecies of the FR turbo manifold. That is another huge aspect as to why i was able to make considerable gains in the resonance aspect. I havent figured out how to calculate the primary and secondary frequencies in a n/a header application. I should dig around in the SAE search engine for something, but i havent had to design a header yet. It would be interesting to find the resonance frequencies of the DTR header.

I tried to overlay the dyno plots, unfortunately it came out really crappy. I am still pissed about not having the m22 original plot for overlay/comparision sake.

 

Good info

Not to get involved Jeff, but i managed to splice both charts together with the scaling of the 1st graph. That's all i do at work, so it wasn't too hard.

The Red line is the AIR manifold HP curve.
The Dark Red/Magenta line is the AIR manifold TQ curve.

The ITB lines are still Green (HP) and Cyan (TQ).

And of course the dotted lines are the M22 cams with ITBs.

 

thanks jerseysipos... so 4 of the lines are itb's, and two lines are the air manifold?

if i am interpreting it right, the a.i.r. manifold(red) isn't very impressive here... the blue(cyan?) torque line clearly has more area under the curve.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by danimal &raquo;</TD></TR><TR><TD CLASS="quote">thanks jerseysipos... so 4 of the lines are itb's, and two lines are the air manifold?

if i am interpreting it right, the a.i.r. manifold(red) isn't very impressive here... the blue(cyan?) torque line clearly has more area under the curve.</TD></TR></TABLE>

i checked the numbers on both original charts to make sure the numbers are accurate, and they are damn close.

M22 with ITBs:
Green dotted line (HP)
Cyan dotted line (TQ) (Blueish line)

M22 with AIR manifold:
Red solid line (HP)
Dark Red/Magenta solid line (TQ)

Skunk2 Pro1 with ITBs:
Green solid line (HP)
Cyan solid line (TQ) (blueish line)

From 6700 rpms and up, I think the Red HP line representing the AIR manifold is a stronger curve than the dotted Green line which is the ITBs.