CAI and low end loss

[Nino]

Why does majority here insist that CAI (Injen) for example has big low end power loss? Are there dynos to prove this?

The only place I ever saw CAI lose a bit of power was around 2500 +/- rpm and that is because people lay into gas on the dyno at that point and it takes a bit to establish intake flow, and get velocity going, OEM box being more restrictive gives better reponse here, hence quicker on power, so this is expected, is this what is implied by loss?

Since I did not bother to check on TSX end of things (mine is still stock 04) when I finally did, I noticed a lot of CAI "kills your low end" stuff, and I am curious why are pople saying that, urban legend, or actual dyno examples (same dyno, back to back)? What amount of loss are we really talking about here?

Here is an example of Injen Dyno 04MT, that I was able to find on the web
http://www.angelfire.com/linux/tinky/tsxinjendyno.jpg
you might want to cut and paste this link, I think they block direct linking...
Does anyone have their back to back available?

[VorteC]

I don't know about dyno's but I can really feel it on my AEM SRI. If I start in second gear, and I put my foot down.. a surge of noise comes but I don't actually go anywhere until about 3.5k rpm

[Nino]

I see your point.
In my experimenting with Short Intakes, one thing was usually the case, they are noisy.

Here you have to make sure not to confuse sound for power or lack of

If you look at this dyno, again it is evident that 04 stock tsx MT back to back comparison, actually demonstrates power gain from 3 K +, and slight loss at 2.5-3K using AEM SRS intake.

http://www.vtec.net/articles/article...tovtsx_aem.gif

This would indicate that you are actually making more power everywhere other than under 3K, and even there penalty is not major.
Stock car might be slightly better 2-3K rpm, but after that aftermarket is better.
I suspect that stock intake resonance is around 2750rpm, and it would explain a lot of these dyno charts and also why it is hard to beat stock at that rpm...

[narci]

I don't think high end power is really an issue. Low end power is where a majority of people need power.

For me, I rarely go over 4500 rpm so losing any power below that is critical.

I guess that's why for the 2009 TSX, the K24a engine was vamped up to have more low end power, 174hp lb/ft of torque and relatively the same high end at 201hp lb/ft.

Here's apretty good write up by MR.

http://www.tsxclub.com/forums/showthread.php?t=19741

[pizzaman555]

I had an Injen and hated casue of the low end power lose and also hated hearing it when ever I went over 3000 rpms.

[griffojm]

The low-end loss coupled with the rise in noise is the reason why I have kept mine stock.

[Noel]

The low end "power" here refers to Torque, not BHP. While a CAI is almost always primarily designed for mid to high RPM gains on torque and BHP gains due to it's basic design construction, this mid to high RPM gain results in a sluggish low RPM torque loss - Unfortunately you cannot have the best of both worlds, so you either lose out on low to mid RPM or mid to high RPM.

The Injen dyno graphs speaks for itself. The power is gain significantly through mid to high RPM without question. However, compare that with the Mugen or J's Racing intake, the Mugen or J's Racing intake is bias to improve low to mid RPM torque and achieves a better "driveability" experience in exchange for lesser mid to high RPM torque and BHP gains.

[ckelleyfla]

[Nino]

Do you have Mugen or J's intake dyno to share?

I would like to see those graphs...

Also, can anyone tell me what is the pipe diameter for Injen CAI, and what is the diameter for Fujita CAI?

Judging on responses up to now, it would appear that 2-3K rpm TQ drop is what people are complaining about, which is understandable, even though personally real loss is not that big for me to worry about and loose all that benefit 3K+.

On the other hand TSX is a nice car, and having it sound like a blender on 10, is somehting of a concern to me, so this I agree with as an issue...