Dyno plot, EP with only an AEM CAI

[B18CXr]

4,100 miles
10W-30 mobil 1

http://www.we-todd-did-nc.com/~burnittotheground/pictures/siplot.jpg

[02blksi]

not to shabby at all! With that 2.25 midsection youll see those numbers jump a good amount. IMO! Since i installed my 2.25 midpipe yesterday the good ole butt dyno tells me it helped a good amount. Ill hit the dyno asap to get some results. BTW how much did you pay for your cai?? thanks --joe .

[ArcticBlueRsx]

i wish my car had a flat torque curve like you guys have...in order for my butt to make torque i gotta hit vtec (5.5k)

[jaydub]

I suck at reading dyno sheets, but what was your baseline? :)

[B18CXr]

sorry.....i wish i had a base line.....


Maybe some one else does??

[K20ACTR]

Does anyone else notice that the power keeps rising? We should be able to easily raise our rev limiter with some of the new programs because every EP dyno i've seen they are still making power at our redline.

[02blksi]

yes, everyone who has dynoed their ep (myself included) says that with a couple more rpms, some higher numbers would folllow. --Joe

[DocofMind]

You def need to raise the rev limiter. Some stronger valve springs are definitely in order.

The Vtec engagement is at 5000 correct? Looks like you would get more power by rasing vtec a few hundred rpms as well. Anywhere from 5300 - 5500 would be good.

[JSIR]

thanks for the info, that is interesting. Further supports my theory that you need all the three parts - intake, header, and exhaust - in order to actually see the big gains on this car. Doing the exhaust or intake mods individually doesn't add a huge amount, but once all three parts are in place the gains are pretty substantial. I dyno'd with myeverlovinsir who had the AEM intake, DC header, and 2.25" midpipe (stock muffler), he got over 147whp, so looks like there is a good 7-8 whp to be gained by the header and midpipe mods when combined with that intake.

The torque curves get even flatter (and higher) once the other mods are added, and the power curve is almost vertical at redline. I think Hondata's 7300 rpm redline should be sufficient for our cars even when they are modded, but I would have liked to see 7500. There is a post about dyno runs of 3 EP's on this forum which offers a good comparison.

[myeverlovinsir]

Originally posted by JSIR
thanks for the info, that is interesting. Further supports my theory that you need all the three parts - intake, header, and exhaust - in order to actually see the big gains on this car. Doing the exhaust or intake mods individually doesn't add a huge amount, but once all three parts are in place the gains are pretty substantial. I dyno'd with myeverlovinsir who had the AEM intake, DC header, and 2.25" midpipe (stock muffler), he got over 147whp, so looks like there is a good 7-8 whp to be gained by the header and midpipe mods when combined with that intake.

The torque curves get even flatter (and higher) once the other mods are added, and the power curve is almost vertical at redline. I think Hondata's 7300 rpm redline should be sufficient for our cars even when they are modded, but I would have liked to see 7500. There is a post about dyno runs of 3 EP's on this forum which offers a good comparison.


JSIR, I have noted a major flaw in my Dyno run, I was running
my intake with the rad hose directly on the intake, shame on me.
I will expect much better gains having raised it up off of it.

Before.
http://www.imagestation.com/picture/sraid37/p9cdfc6c1cd8f4aab017f05d7c60b11ba/fd1764e4.jpg

After.
http://www.imagestation.com/picture/sraid37/pd5e7e214d1023c79302da10b89c286ca/fd1764cf.jpg

Never noticed this till I did my heatshield install. Suffice to say
that every other person running the AEM CAI is prone to this.
Please check this!!!! tks

[JSIR]

yeah my short ram intake does that as well, mine kind of rubs up beside the hose. I would try to isolate the hose and pipe from eachother if I was going to keep my intake but I doubt I will have it next time I dyno the car. good idea though.

[myeverlovinsir]

What ya planning JSIR, are you thinking of switching over? To what
may I ask?

[JSIR]

I'm definitely going to get the Comptech Icebox intake when it's released, I've had one before on my other Civic and it was my favourite intake of many that I have tried. There are others such as Mugen and the Idol intake which are similar but they are a bit too expensive for me, so I will wait to check out the Comptech unit. I just bought the K&N intake for dyno testing purposes as I was very frustrated when my exhaust and header upgrades showed almost no gains by themselves. Once I put on the intake it brought up all the hidden power 12-13 whp gains ! . If I was to dyno again with the hood closed on my car, my numbers would drop by 4-5 whp, probably on the street in hot summer weather the drop would be even larger due to the short ram underhood design. So I need a cold air design, and I found the Comptech unit the easiest one to live with over the years.

[02blksi]

for those of you with the problem of the radiator hose rubbing against your intake summit racing sells intake heat shielding wrap. Very cheap, yet effective to lower intake temps. Just some food for thought. Or if you are like me go to home depot and see what you can scrounge up that is similar to what summit sells yet @ half the cost. --Joe.

[B18CXr]

The Vtec engagement is at 5000 correct? Looks like you would get more power by rasing vtec a few hundred rpms as well. Anywhere from 5300 - 5500 would be good.



WTF???

[02blksi]

Vtec engages on our ep's @ believe it or not (according to hondata) 2300 rpm!!! thats our high cam switch over. Maybe im confused but thats what it looks like!

so below 2200 rpm -Low cam profile -
2300 rpm - High cam profile


My only queston is, why is their a noticeable bump for lack of a better term @ about 4800 rpm ( i originally thought this was the engagement of vtec.-this bump on power) that is so pronounced on all the dynos i have seen? ---

Im just as shocked as the rest of you at this PATHETIC info. They threw the SI badge on a Fuel economy car!!!!! WTF!!!!

:mad:

[JSIR]

Originally posted by 02blksi
Vtec engages on our ep's @ believe it or not (according to hondata) 2300 rpm!!! thats our high cam switch over. Maybe im confused but thats what it looks like!

so below 2200 rpm -Low cam profile -
2300 rpm - High cam profile


My only queston is, why is their a noticeable bump for lack of a better term @ about 4800 rpm ( i originally thought this was the engagement of vtec.-this bump on power) that is so pronounced on all the dynos i have seen? ---

Im just as shocked as the rest of you at this PATHETIC info. They threw the SI badge on a Fuel economy car!!!!! WTF!!!!

:mad:

I've read that several times and I find it a bit confusing, but every time I have read it they are referring to the base RSX motor and not the Civic Si motor, I am hoping there is a difference. Our vtec system works by having one intake valve fully at certain rpms and then opening the second intake valve fully at certain rpms. One main benefit is to produce good bottom end torque. Now if both valves were open at 2200 rpms what benefit would that have on bottom end for our engines ? - almost nothing, who the hell drives at 2200 rpms in any gear. In terms of your daily driving routine how long would you spend at 2200 rpms ?, maybe like .0000000000000001% of the time - max. This would be useless in terms of building "useable" bottom end torque. The only benefit of that type of system is fuel savings at idle, nothing to do with bottom end power gains IMO. I am hoping this just applies to the base RSX motor as their intake manifold is variable and it builds good bottom end torque on its own.

On the Civic Si engine something definitely happens at 4700 rpms, we definitely get a power gain/surge and revs build much quicker above that point. It would be my guess that the second valve opens fully at 4700 rpms on our engine. You don't see this surge/difference on the base RSX power curve. If it is not the vtec system changing at 4700 rpms then it must be the variable cam timing going into full overlap mode, 'cause something is changing widely at 4700 rpms on our engine to build top end power more quickly. If it was the second intake valve opening at 4700 rpms I can see that type of system being good for bottom end power as I consider useable bottom end power to be 2000-4500 rpms. Maybe because we have a much larger intake manifold (that is not variable) and bigger throttle body that Honda moved the vtec engagement up to 4700 rpms on our cars. I hope that is the case. And remember that our engine makes a good bit more bottom end torque than the RSX-S engine despite us sharing the same intake manifold and the same larger throttle body. How would Honda achieve better bottom end torque on our engine from idle to 5000 rpms if we have the same bore, stroke, intake manifold, and throttle body ?, it has to be through the vtec system as both engines have variable valve timing. I would think our vtec point for the second valve opening is 4700 rpms, otherwise our bottom end would be much worse.

On my car with a few mods, the vtec engagement is actually pretty strong, at 4700 rpms the car pulls much harder and revs build more quickly, quite evident. It almost feels like the old vtec system like the b-series engines had - to a certain degree, although I know the two systems are completely different. The engagement felt much stronger after a few mods though. This is not a resonance change we are experiencing, there is some definite engine change at that point - either vtec or valve timing change, my guess is the vtec system engagement.

[02blksi]

JSIR - everything you wrote I totally agree with, its funny we are always on the same level. we think alike, kinda freiky but cool. -joe. :)

[JSIR]

Originally posted by 02blksi
JSIR - everything you wrote I totally agree with, its funny we are always on the same level. we think alike, kinda freiky but cool. -joe. :)

same name too ! - very scary :eek:

[Surprise]

How does the fact that the si engine does not have an egr valve play in?

[myeverlovinsir]

I was getting a little anxious about responding to the post by
B18CXr, seeing as we touched on this prior in my post about
JSIR, SmoothOperator and myself and our dyno
runs joe. (ended an otherwise nice thread).

Thanks JSIR for putting it so nicely. I concur totally guys, and
am searching for more info related to what we already suspect
about the i-VTEC engagement near 4800.

[JSIR]

Originally posted by Surprise
How does the fact that the si engine does not have an egr valve play in?

by altering cam timing over a wide range, they effectively do away with the egr valve with no ill effects. We still get the crank vapours recirculated into the intake system though, but I haven't quite disected the different parts yet though. I can see remnants of crank vapuours in the bottom of the intake manifold, so they get sent in there somehow.

[Surprise]

By reading the old post of the 2200 rpm vtec point I got the impression that the lower crossover was there to replace the egr valve therefore helping the smog and fuel economy. I wonder if that is what confused them as well, or maybe it was just me?

Thanks for your explanation, makes sense now.

[tkm]

Seems like a lot of you are new to Honda Motors or something. All of my old D series non-vtec motors came "on cam" around 4500rpms or so, and we know they did nothing fancy. This is just the sweet spot of the motor and has nothing to do with vtec engaging or valves being opened or anything.

[2K2RedSiR2NV]

Thanx for the heads up on this myeverlovinsir . I'll go check this out right away!

[Glix2]

You have it all wrong.

below 2200 rpm 12 valve
above 2200 rpm 16 valve
intake vtec 4800

That's why you see two bumps on the dyno.

[ULTRAMANIA]

dood that's some nice numbers mang... that's significantly better then just stock, and you just got the AEM CAI.. not bad at all.. i'm liking that... our engines got so much potiential... heh.. i love it.. good numbers!!!

[myeverlovinsir]

Originally posted by Glix2
You have it all wrong.

below 2200 rpm 12 valve
above 2200 rpm 16 valve
intake vtec 4800

That's why you see two bumps on the dyno.

There are 2 lobes on the intake side only, first lobe is start lobe.
it contols the lift on both of the intake valves. I-Vtec engages the
larger lobes @ ~4800 rmps for both intake valves. thats all. The
problem with running this is that there is increased friction
on the lower lobe because it has to support both intake springs
at once. A nicer setup would have both independantly sprung on
their separate lobes. such as the RSX-S.

btw: the base rsx is the only setup that I have heard of 12 then 16 valve thing. Don't think this applies to Si(R). jmo

[sicivic2002]

Not to be negative or anything. But in the January SCC yeah I know SCC but anyways, they dynoed a stock SI at 138whp and 124lb-tq at the wheels.

[Glix2]

Originally posted by myeverlovinsir


There are 2 lobes on the intake side only, first lobe is start lobe.
it contols the lift on both of the intake valves. I-Vtec engages the
larger lobes @ ~4800 rmps for both intake valves. thats all. The
problem with running this is that there is increased friction
on the lower lobe because it has to support both intake springs
at once. A nicer setup would have both independantly sprung on
their separate lobes. such as the RSX-S.

btw: the base rsx is the only setup that I have heard of 12 then 16 valve thing. Don't think this applies to Si(R). jmo


Why wouldn't it apply to the Si? It's the same engine with different intake manifolds. I'd give credit to the ULEV certification on the motor based on that alone.

[myeverlovinsir]

if you read the fine print, the honda Si(R) is LEV equivalent. Not ULEV
such as the Insight. I think we qualify for this stipulation based
on the proximity of the cat to the head, the frozen exhaust cam and EGR modifications. Even the type R is considered LEV.

According to current guidelines our cars are good for upto year 2010 in emission standards. Unless the Kyoto protocol gets nuts.

[Glix2]

Originally posted by myeverlovinsir
if you read the fine print, the honda Si(R) is LEV equivalent. Not ULEV
such as the Insight. I think we qualify for this stipulation based
on the proximity of the cat to the head, the frozen exhaust cam and EGR modifications. Even the type R is considered LEV.

According to current guidelines our cars are good for upto year 2010 in emission standards. Unless the Kyoto protocol gets nuts.

The cat to the head? Isn't it the proximity of the cat to the exhaust manifold?

Your right about the SI, RSX and RSX type S all being LEV-II. I hadn't looked up the Type S emission standards yet just checked it out.

(acura quote)
In the 160-hp RSX, the VTEC modulation of i-VTEC works on the intake valves exclusively, using a 2-rocker arm design. At lower rpm, the second intake valve opens only partially, creating a desirable swirl effect in the combustion chamber. At higher rpm, both intake valves open fully, for quicker, easier breathing and full power output, reaching 160 horsepower at 6500 rpm and 141 lb-ft of torque at 4000 rpm.
(end acura quote)

This still doesn't explain why honda chose to only run 12 valves below 2200 rpm. They don't list it as having anything to do with the LEV-II certification. I was either wrong about it being part of LEV or it's one of those under the rug kinda things.

I haven't found anything that says the SI version does or does not use this. Just have to wait until hondata releases more information.

[B18CXr]

they dynoed a stock SI at 138whp and 124lb-tq at the wheels.


different dyno's provide different numbers..

[myeverlovinsir]

Originally posted by Glix2


The cat to the head? Isn't it the proximity of the cat to the exhaust manifold?

Yeah, I meant that the cat is located closer to the head, much shorter
header(exhaust manifold) and as a result much higher temps
and efficient burn off of hydrocarbons. (But yes distance from the header is important as well.);)

[CleanBlackSi02]

I'd like to see some other figures with just a CAI and Hondata on the Si...as opposed to the Hondata tester base RSX...