[Louse76]

I saw a discussion about the powerband on a GSR, but I haven't seen a mention about the powerband on an RS. I assume its lower with the extra low end torque, but I'd like to hear it from an expert.

So where would you say the "powerband" would be on a B18B1 w/CAI and DC 4-2-1/gutted cat/2.25" exhaust, everything else stock?

 

[non-VTEC]

the power band on a B18B would be from about 3500-4000rpm all the way up to about 7000rpm........

 

[Louse76]

well i wouldn't think it would be that early or that late... its not going to make the most power all the way past its redline and i thought the powerband would be a little later than that.

 

[IntegraBad18c]

Try timing your speeds from 0-60, 20-40, 60-80 and note time and rpm start and rpm end.

That's how the biker guys in one of Tuan's articles did it.

 

[dragontegz]

you probably know this by now, but i thought i'd mention that a gutted cat is going to take away power by creating exhaust turbulence... (not to mention making your car smell funky) replace it with a car sound cat when you get a chance. just a suggestion. i'm not trying to tell you what to do.

 

[BlueTeg]

the power band on a B18B would be from about 3500-4000rpm all the way up to about 7000rpm........

In my opinion the B1's powerband starts at the "aem humb" which occurs in the low to mid 4,000 rpm range and extends to 6400-6500 rpms.

With the mods that he has the engine will actually fall out of the powerband well before 7,000 rpms. The B1's power will actually start to fall off around 6,400 rpms.

Its not uncommon to see the engine produce 10 less whp at 6800 (redline) than at 6400 (end of the powerband) imagine what the whp ratings are at the fuel cut which occurs even later than redline!

However, do not mistake the powerband location with optimal shift point when you take your car to the track. There is a lengthy and informative thread detailing the importance of shifting at redline to keep your car in/or closer to the powerband on the upshift.

Here's the link:
redline vs. max hp point

 

[Louse76]

you probably know this by now, but i thought i'd mention that a gutted cat is going to take away power by creating exhaust turbulence... (not to mention making your car smell funky) replace it with a car sound cat when you get a chance. just a suggestion. i'm not trying to tell you what to do.

I understand, no problem. I'm thinking high flow cat eventually, but I thought I'd try out the gutted cat when I install the 4-2-1 DC headers so I could see first hand the difference mainly. Plus, I don't think I'd lose anything over the non-gutted cat since mine is probably so filled up with crap after 109k miles.

While we're on the topic, does anyone know around how much its going to cost me for a carsound or one of the other hi-flow cats and maybe a good place to start looking?

 

[Louse76]

In my opinion the B1's powerband starts at the "aem hump" which occurs in the low to mid 4,000 rpm range and extends to 6400-6500 rpms.

With that in mind, doesn't it seem that the B18B1 has a pretty wide powerband and its possible to stay in the power band the whole time? I'll have to analyze where my RPM's drop to after shifting at redline vs at 6400 etc. I assume I will confirm that redline is the best place to shift as has been proven, but I'd like to see it first hand.

Also, one has to remember that everyone is always analyzing the B18C1 powerband with its gearing, rarely are they thinking of the B18B1.

 

[BlueTeg]

the b1 has a wide powerband. unfortunately the gears are way too long.

 

[StyleTEG]

www.ipsracing.com has great prices on carsound cats
Also try sending a PM to SMSP on TI, he also sells carsound cats.

 

[BlueTeg]

Dave from smsp sells them for about 175
IPS sells them for a few bucks more.

 

[JustinKlemgold]

I saw a discussion about the powerband on a GSR, but I haven't seen a mention about the powerband on an RS. I assume its lower with the extra low end torque,

I see this said a lot around here and it has me wondering.

OK, not that I don't believe you, but I look this up in the articles section and it says that the GS/LS/RS has 124 @ 5200. While the GSR has 128 @ 6200. Sure the GSR's torque peak comes 1,000 RPM later but it also has a higher redline.So, how do you figure it has more low end torque? Does that mean the GSR has more high end torque?

And it seems that everyone makes this out to be a huge advantage and I don't understand that either. It's 4lbs.

 

[MichaelDelaney]

peak is one number...not a range or average....dynos looking at higher peak numbers can be misleading if the overall average power is lower...

it just confirms that a lower rod ratio motor has more low end or earlier hauling power due the the way the piston speed induces max. "suck" on the intake stroke. the lower rod ratio motor will have more cylinder filling closer to TDC or the first part of the intake stroke rather than at the later part of the intake stroke. So at low to mid rpms, the lower rod ratio's piston geometry fills better and makes more power in that powerband range compared to a higher rod ratio motor.

regarding the 4 lb ft difference:

4 ft lb x 6200 rpm/5252 = 4.7 hp x 0.85 = 4.0 whp

do you consider a 4 whp gain significant?

 

[Louse76]

Hey guys... If I shift at the HP Peak, I drop to 4000RPM approx... wouldn't that be at the beginning of the powerband according to some here?

Or is that not the powerband?

 

[BlueTeg]

Louse:
What rpm are you defining as peak hp?

I'm not really sure if there is a concrete definition of what begins and ends the powerband, but, I as I stated earlier: the B1's "sweet spot" is from the AEM hump (or 4,400) to about 6,400 rpms.

Try taking the engine up to the redline.....you'll fall a couple hundred rpms higher on the upshift.

 

[BlueTeg]

Here's typical example of an LS mildly modded with:
aem cai, header, carsound cat, and greddy evo exhaust

Notice the difference in power from 4,000 rpms vs. 4,500

Also notice the large bump in power from 4000-4400 rpms..........signature "aem hump".

 

[TysonB11]

I was wondering if someone could answer louse76's question, from page 1.

only difference is i have a B18a1 with stock transmission. How do redline upshifts match up with our powerband? Sorry if this has been answered

Could i at least get a link to it if it has?