Building some HPs - Intakes: Injen evolution vs Skunk2
 

Hey guys. I've decided to go for a NA build because forced induction is hard to get where I live. I'm going to use a catless header (I'm thinking custom built in Argentina) and need to decide on an intake that'll have better results in high rpms. After installing these I'm going to the local dyno for a tune.

I've read some official and unofficial dynos for these systems, and the old injen evolution one seems to give the highest gains, but that model is discontinued for some reason. Anyone have experience with the evolution (old) injen cold air intake?

Also I've seen the skunk2 has a sort of removable piece where the maf sensor is. This should be removed if I'm to tune it afterwards, right?

I'm still pretty new in everything, so thanks for your patience :D

Most dynos of a CAI only saw minimal gains mostly from having the AFR leaned out, once MAP rescaled and retuned the gains where minimal. Still present for some, but not noticeable enough to feel. So don’t expect a huge difference.

Options from lowest gain to best.

Perrin inlet tune with OEM box and performance drop in filter,
TRD Intake / Grimmspeed CAI both probably similar gains
Perrin inlet tube with Perrin CAI has most potential especially top end but only if you are willing to remove bumper for install and filter cleaning.

I wouldn't waste time and money with intake system since there is no HP gain there. Just do the catless header + tune and you gained all HP you can. If you want more HP, you can go with E85 if it is available in your area. That is all you can do to increase HP short of FI. I would better spend the money on shocks, wheels, tires, and brakes for handling ... and exhaust for sound.

I agree. Maybe the Crawford powerblocks if you want midrange over topend. Helps with DD. But try to get a deal, they are not cheap for what they are.

I seem to be changing my mind everyday with what I read! So intake would be 5hp/tq tops, unnoticeable feel?
Budget is limited, mostly because of massive import tax and shipping, so I've gotta think again I guess.

Then do, like many do. Get 80% of aftermarket intake gains by $50 aftermarket air filter. Should do for prerestyle. (one of things improved on MY2017 was airfilter to less resistive, thus less to gain from aftermarket one).

Spend the money you'd waste on the intake on tires!

Unfortunately the idea that there are gains to be made are from people that did get a huge improvement from changing their horribly inefficient systems on cars like the base Civics and Neons. Those cars can be improved greatly by a CAI.
The intake on the Twins was very well designed to give maximum efficiency right from the start. Yes that it can be marginally improved with a higher flow filter (hell they did that themselves in 2017) but even then you are looking at an immeasurably small improvement.

On many cars especially older they essentially have a hot air intake sucking air from engine bay and changing the placement of where the intake draws air to a much colder air path generates more power from sucking in colder air. Our stock intake is already a CAI with utilizing a “snorkel” so we already have that benefit.

So the only way to improve over stock is to either make the filter less restrictive (drop in filter) or increase the filter surface area (aftermarket system) in order to have either of these generate more power however it has to be a limiting restriction with the engine actually able to suck in more air than it already is (filter not large enough or flow enough) I believe once you have improved the exhaust flow (catless header) and are able to change the intake/exhaust cams duration with tuning then it is possible the stock system might be a very minor restriction especially in higher rpm.

Performance air filter like K&N is about 1ftlbs/1.5whp

TRD intake is similar to OEM but has an air filter angled in a larger box to have Larger filter with more surface area, grimmspeed utilizes a cone filter to have more surface area. Both are about 1.5wtq/2whp

Perrin is the only “pure” cai on this list having the filter placement relocated to where the snorkel end would normally be and thus now has way more room for a very large cone filter about 1.5x the size of grimmspeeds. Is about 2wtq/2.5whp.

Some people mod their car and have zero measurable acceleration improvement but swear up and down they can “feel” more power...

others can’t “feel” any difference unless its at a minimum 6+whp or maybe 2/10th off 0-60.

So you won’t “feel” any difference from a CAI (or it’s all in your head) BUT with NA every last little bit does add up. NA is a game of inches not feet... max potential is very limited and low compared to FI.

If you have the funds go for it, but there are “better” mods to do 1st.

That sounds like a nice option. I've just read this thread and it seems to be the bang for the buck.

Already got those. I'll likely be getting beefier looking brakes this or next year too :)

I didn't know that! There's a lot of civic tuners here, most go for some pretty big intake tubes that look... interesting.

That's a nice, simple explanation. I'll likely go for the airfilter, and save for more worthwhile upgrades later.

Thank you guys for the feedback!!

Decat OEM header and frontpipe, snorkel mod, oem style "good" dry aftermarket airfilter.

Only cost is the filter and some gaskets.

With the money saved get a ECUTEK (with racerom) tuned by a pro on a dyno and have fun.

On 98RON you should see near to 190-200hpatw peak power and good gains everywhere else.

Or, spend alot of cash on aftermarket parts for some stickers and typical gains.

TRD intake in red vs Silicone intake tube + K&N drop-in filter in blue. Both setups were dyno tuned. Catless header and catback with E85 iirc.
https://www.ft86club.com/forums/atta...1&d=1571429366

Obviously temps, humidity conditions etc.. could account for 1-2whp difference between runs. Although with pre 5.5k rpm being so similar that might not be as big of factor. Or the drop could have been dirtier restricting flow at top end a little. But I still think its clear TRD has some more power.
Looks to be about a 3whp/2wtq avg gain from 5.5k-7.5k.

Another thing most people don’t consider. Is even if factory filter isn’t a restriction, or maybe it’s a slight restriction but a drop in isn’t and still has a tiny bit of head room and that’s why other cai don’t make more power. If drop in has say 5% more flow than the engine can use going beyond that would make no difference.

BUT after say 5k miles it gets dirtier and starts clogging up and flows 10% less than it did brand new. It is now a restriction where as a cai with say 15% more flow headroom after it’s dirty and flow drops 10% is still flowing more than the engine needs. So it might not show more power both tested brand new, but one might continue to make the same power while the other slowly drops off over time until replaced again.