scuc

I recently got a baseline dyno. I have comptech headers and the icebox. In the process I found out that my IMRC was bad. You can see the tq curve take a dive at around 4100 rpm. It's getting replaced under warranty right now. Once this is fixed, will my tq # go up at all? I was hoping to get closer to 230hp to the wheels, but it didn't happen. I'm thinking about getting the UR crank pulley next.

my car:
2003 Acura CL-S 6spd
CT Headers and Ice box
everything else is completely stock
225 HP 195 tq

Accord_V6_400m

iTrader: (1)

You will see a significant mid range torque boost, customarily you should see the torque curve go up and stay that way past 4K. You should be able to get 210tq as soon as the IMRC starts working again. Which will easily get you the 230whp that you were looking for.

Accord_V6_400m

iTrader: (1)

What suprises me is how your torque doesn't eventually catch up like mine did at 6K so the torque values at 3K and 6K were similar just the middle was gone. This was the case when my valve was close the whole time.

With the valve open the whole time you would usually see a torque difference of 10-15 btq when the valve is supposed to kick in at 4K.

So your midrange and high end will be there but your low end will suffer a little.

If you can maintain your low end torque curve till 6500rpm so around 200btq you should be able to get 245-250btq which is around 230whp if not a little more.

MikeCLS6

I thought a stock 03 CLS-6speed dynoed between 215-222 at the wheels

Accord_V6_400m

iTrader: (1)

For the most part they do, im just being conservative with my numbers and hes really losing a lot of power from the malfunctioning IMRC as for peak hp hes losing more then I would have thought, but I guess thats because of his level of mods too.

scuc

Wow, so the bad IMRC is hurting my numbers that much? That sucks. Good thing its covered under warranty. I'll probably dyno again if/when I get the pulley see if the numbers are where they're supposed to be or if I just have a weak CL.

Accord_V6_400m

iTrader: (1)

Just hang in there, with all my mods and some tuning, I managed to get 278bhp on that dyno which is brake horse power, which is a a little higher then WHP. Im trying to go for 300bhp, but its not going to be easy without cams, fuel cut off removal, possibly some more exhaust mods etc.

rp_guy

... ? bhp is crank hp, Type-S's should be 260 stock (~250 SAE)

scuc

so since the graphs say "flywheel" torque and power, that's only a measurement to the crank and not to the wheels? Damn, if that's true then my numbers are really low...

scuc

nm, I've been doing some reading, and I guess the numbers I'm seeing are hub hp and tq, right? Since it was done on a dyna pak the wheels had to come off, so the numbers were measured at the hubs. I'm guessing this means that the numbers are just a little bit higher than whp, like Accord_V6 said (sorry, don't know your name).

rp_guy

yeah, you can assume that it's slightly higher since the engine doesn't have to rotate the mass of the wheels.. it shouldn't be more than 5% difference though.

when are you getting the IMRC fixed ? i'd like to see the #'s on that, though.

scuc

I just got my car back yesterday. The dealership had it for the whole week cause they didn't have the parts on hand and had to get them shipped in. My first impression is that the car is pulling a lot harder than I remember. It feels a lot stronger and quicker, but then again that could be due to the fact that I've been driving a loaner MDX this whole time. I don't know if I'll get a follow up dyno any time before I get the pulley, just cause the closest place to me charges $99 for three pulls. Who knows though, I really want to find out how much I'm getting with a working IMRC. I was lucky enough to get in on a group dyno and got 3 pulls for $50, which is the graph I have posted here.

Accord_V6_400m

iTrader: (1)

Yep brake horsepower tends to be a nice way of measuring gains just because you don't have as many variables as you do with wheels/tires.

You should feel a lot more midrange, and VTEC should kick in a little less hard since the torque transition won't be as high since your not coming from your lowered midrange to "VTEC power". I still think your peak numbers should have been a little higher with everything considered but those are my experiences and maybe because of my mods my high end did not suffer as much as yours did.

rp_guy

can you please stop calling it brake horsepower ?

Brake horsepower (bhp)

Brake horsepower (bhp) is the measure of an engine's horsepower without the loss in power caused by the gearbox, generator, differential, water pump, and other auxiliary components. Thus the prefix "brake" refers to where the power is measured: at the engine's output shaft, as on an engine dynamometer. The actual horsepower delivered to the driving wheels is less. An engine would have to be retested to obtain a rating in another system. The term "brake" refers to the original use of a band brake to measure torque during the test (which is multiplied by the engine RPM and a scaling constant to give horsepower).



a more correct term is hub hp..

scuc

I hope that's the case. Which mods do you have other than I/H? Is it the radiator, exhaust, and neo?

rondog

iTrader: (1)

trust me, I had a bad IMRC valve twice, took me a while to actually check underhood becasue I doubted myself. Now with my car back, the difference really showed itself the 3rd day I had the car back with the working IMRC, car just bolts after 4k. When you shift in high rpms without the IMRC, there is no lung or howl from the engine, like driving a CL-P with a manual gearbox, feels like something is wrong. I even found myself wanting the SC when my IMRC wasn't working, I thought I just got used to the power.

Accord_V6_400m

iTrader: (1)

A stickler for terminology
Your making me feel as if brake is some sort of deragotory word
If it really bothers you just pm me or ignore me
I suppose i'll leave the term as the british left it

Well scuc these are the following mods that I have:
AEM CAI, port/polish UIM, IM spacer, UR SS pulleys, Comptech headers, RT cat, Magnaflow catback, Apexi Neo, VSA delete (think only AT models have the VSA TB?). Thats pretty much it for mods unless you have more specific questions.

Allout

You had this done at Driving Ambition? You know that this is Shad Huntley's place don't you? What did Shad have to say about your Dyno? Shad's a wealth of knowledge on these motors.

scuc

Yah, I know Shad. He's a pretty nice guy. He immediately noticed that there was a problem, and pointed it out to me. He couldn't really do much besides that. He was actually glad to dyno my car cause he was familiar with it. All the other cars were Supras (it was a Supra meet).

All Mine

Ouch. $99 for 3 pulls? Does that include AFR? The shop I work at only charges $65 for 3 pulls with AFR.

But yes, the IMRC should get you back to some better numbers. If you want to make the drive over here to GA, where you can use 93 instead of 91, you'll get some better numbers as well.

Have you thought of using Nitrous, as well? That's a good, cheap way of getting nice numbers. Go with a 75 wet shot, like I, MattG, and a few others have done.

CLS6SpeedNupe

Before i go dyno my car thursday, how can I tell if my IMRC is good? its $75 bucks for 3 pulls and the only loss of power reflected in my dyno that I wanna see is a bad Air/fuel curve.

scuc

you could have someone look at your IMRC while you rev your car past 4100 rpm, if it doesn't move, then it's broken. There's a video around here somewhere that show's what it's supposed to look like.

CLS6SpeedNupe

oh u talking about that opens and closes, goldenish looking thing that looks like the thing on the throttle body.

Allout

Info on the Actuator:

http://www.geocities.com/~gamesmgr/chod/acura/#Driving6

Accord_V6_400m

iTrader: (1)

Good post a picture and a video helps a lot more then us just describing it :p
Also its supposed to open up at 3800rpm, a thousand shy of VTEC.

Cmanuel

I know its an old thread But I"m curious to see if OP re-dynoed the car after fixing the actuator