NSteXpo 2002 Dyno Day Report - now available!

[Yellow Rose]

Q - Well then, so why did you state that you thought the concept of "area under the curve" was silly again?

A - because if someone is interested in HP at the upper end of the RPM range, they will not (they should not) be concerned with the lower end of the RPM range.

Q - How else would one know which size fits the best if one had no access to "area under the curve" data?

A - the dyno plots are posted within this very thread; therefore, we do have access to the data.

Q - You seem to have contradicted yourself in your own post.

A - How?

 

[Number9]

Originally posted by Jimbo:
But in the positive displacement air pumps don't you also have that problem?

Yes, but the effects are not as bad at low/mid RPM because in the centrifugal case "boost builds exponentially with engine rpm..." So it necessarily falls off faster (i.e., at low/mid rpm) than the roots/whipple case if you assume the latter build boost linearly with RPM.

 

[nsxlr8]

I agree with Where the area under the curve that you will use most. But in the mind that you are purchaseing a supercharger / turbo / nitrous kit strictly to get more power for more acceleration, I would want to look at usable full acceleration. My car drops down to 4900 rpms in 2nd gear. I want to look at the average power from say 5Krpm to 8Krpm and compare the average horsepower figures. Comptech (In this small dyno day comparison) Wins. If I had a 6spd I would want to Get the average and compare one kit to another from 5800rpms to 8k.

Lots of comparisons here. I just can't beleive that there isn't another Dyno Graph of one of the 30 installs that represents the current 6lb.kit? Why was there a 4lb pulley on the car in Dallas? (Another debate or simple reason maybe?) Will one of the owners please stand up and post a chart so we can compare? There are 30 of you right? Maybe minus a few installs that haven't happened yet. Any owners out there who have no monetary gain in this debate? I think BBSC has a right to claim victory here. Why hasn't anyone?

 

[burbel]

Actually, I don't think any of the 30 installs have happened yet, they are scheduled, and still awaiting completion. I was originally on for the Dallas installation, and that was June 21st, I believe.

As for the power range, I do want the supercharger for stronger acceleration, but, for the most part, I don't really car about power from 5k on up (only that it doesn't drop considerably). When I'm driving around at 30 and want to go faster, I will drop it into 2nd and give it throttle. Therefore, 3k rpm performance is a big issue for me.

I don't know about you, but I almost never find myself in a situation under "full acceleration". To me, in 1st gear, there is plenty of power. In 2nd, 5k rpms is 50mph, and the highest speed limit other than on the highway. So, in that case, the areas I care most about are the 2k-5k rpm ranges, and the area under the curve there...

If you want to see the 6lb kit, doesn't the dyno chart on ScienceofSpeed's site show those numbers? I made my decision to go with the Comptech (or another setup) over the BaschBoost from that chart, which shows significantly, IIRC, higher torque levels in the upper ranges than stock.

 

[nsxlr8]

"That equation holds true only for a car dynoed with a 1:1 gear ratio. The NSX does not have a 1:1 gear ratio. The factory gear ratios are 1st (3.0), 2nd (1.7), 3rd (1.2), 4th (.96), and 5th (.75). Common practice for the NSX is to dyno in 3rd gear, as the gear ratio is closest to 1:1."

Damn, Now I'm getting frustrated. I hope you were just typing fast (As I always do and spell things wrong or mix things up) But, really not intending to be a Smart a** here, wouldn't 4th gear (Which I and everyone else I know Dyno's in) be closer to a 1:1 ratio than third? 1-.96(4th gear)= .04 1-1.2(3rd) = -.20. Isn't a .04 difference closer than a .20 difference (Obviously a redundant question) So, now my new question is, which cars and or dyno charts were Dynoed in Third Gear?

I found the Dyno i was asking for in the most recent post (Science of Speed sight) and i wanted to compare, but was it dynoed in third gear?

 

[Rubber Chicken]

From the looks of the responses from the Pro-Comptech and GruppeM crowd they seem to be ignoring the fact that the BBSC was only on 4 psi!

Look at the stock hp curve, and compare it to the BBSC, now cut that in half, that's still a ton of gain (btw 5k and 8k) and that's only 2 psi worth of boost.

The 4 psi graph is only two thirds of what a 6 psi graph would be. I know that sounds like I'm talking down to you guys, and that its so obvious, but stop and think about it a second.

Multiply the hp gain (not the total hp) by 1.5 and that (ideally, since we're ignoring decreasing compressor efficiency) and you'd get one HELL of a hp curve.

The BBSC @ 6 psi would surpass the CTSC and GruppeM SC at 6200 rpm and be well on its way to 400. And for a car that redlines 8 and shifts to mid 5's that's not too shabby at all.

 

[NetViper]

The BBSC @ 6 psi would surpass the CTSC and GruppeM SC at 6200 rpm and be well on its way to 400. And for a car that redlines 8 and shifts to mid 5's that's not too shabby at all.

I don't think anyone is doubting the HP ablities of the BBSC. It will put out more power than the other two system. What people seem to be concerned with is the amount of torque the Gruppe M and Comptech produce. For normal daily driving, they are a better solution. From 5K up, yes BBSC is better, but from 3-5K, where the majority of street driving occurs, the other two are more desirable. Of course, thats just my opinion.


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NetViper -= 100% Stock EBP 2000 Civic Si =- Still looking to get an NSX, but at least I can live life at 8,000 RPM!

 

[burbel]

Right, I'd have to agree. I don't think that anyone (or very few) here doubts that the BBSC is in any way not the most powerful (in terms of HP) supercharger, and that it wouldn't be the best for track usage (1/4 mile, road course, etc).

The only point that the dissenters are making is that, for a daily driver, the Basch Boost makes little sense, as it's gains would not be realized on a daily basis, whereas the Comptech and Gruppe M could be enjoyed every drive.

 

[JSG]

Originally posted by burbel:
Actually, I don't think any of the 30 installs have happened yet, they are scheduled, and still awaiting completion....As for the power range, I do want the supercharger for stronger acceleration, but, for the most part, I don't really car about power from 5k on up (only that it doesn't drop considerably). When I'm driving around at 30 and want to go faster, I will drop it into 2nd and give it throttle. Therefore, 3k rpm performance is a big issue for me.

I don't know about you, but I almost never find myself in a situation under "full acceleration". To me, in 1st gear, there is plenty of power. In 2nd, 5k rpms is 50mph, and the highest speed limit other than on the highway. So, in that case, the areas I care most about are the 2k-5k rpm ranges, and the area under the curve there...

I am receiving a production BBSC June 3. I had the very same concerns about this unit after release of the dyno charts. Keep in mind a few things:
1. When you want the kick of a SC, it is not happening at 2-4K, but at WOT. You will get that power very quickly.

2. We have heard a lot of theory here but very little real life testimonial about the production BBSC. Mark has assured me that I will have more power and fun than I can probably handle with the production unit and that I will not be disappointed. This is from a man who has installed, tuned, and owned all three SC options. Given his experience and reputation is this community, I would value his opinion very highly over all the above theory. He even offered to remove it and install another SC if I was not happy.

 

[Number9]

Originally posted by JSG:
1. When you want the kick of a SC, it is not happening at 2-4K, but at WOT. You will get that power very quickly.

That's not right. It's not even wrong. (You physicists will probably get a kick out of that quote!) The high-boost CTSC will produce more torque between 2K-4K at WOT than the stock engine makes at its torque peak.

Look, it's a simple decision - big HP at the high end, BBSC, big torque at the low end, roots/whipple (BTW, notice how well the data supports the theory). Pick one and be happy.

P.S. I've got a centrifugal blower on my commuter car and a whipple on my weekend car and they're both great so I'm not advocating or disparaging either.

 

[true]

Originally posted by JSG:

1. When you want the kick of a SC, it is not happening at 2-4K, but at WOT. You will get that power very quickly.

Strange comment...I wasn't aware you couldn't be at WOT between 2-4k RPM...but i found it. It's under technical service bulliten #32342132 and saw the issue:
Please abstain from pushing the throttle to 100% between 2k and 4k RPM.


not.

2. We have heard a lot of theory here but very little real life testimonial about the production BBSC.

Do some research and you'll find MOST of everything that has been said is law not theory. Don't be so blind.

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jack of all trades, master of some.

 

[Rubber Chicken]

This may just be my personal opinion, but no one races while cruising. You don't pull up next to a 348 and say "Hey I'll out-cruise you to the next stoplight, Max rpm's are 4500."

If you wanna win a race, then have more hp. If you're complaining about not having torque when you hit it, then shame on you for being in the wrong gear. In fact, that's pure Honda philosophy. All the Integra's, Preludes, and Civics all deal with the peaky powerbands, if you wanted a car that broke the tires loose at 3k then you should've gotten a pushrod V8.

I say don't turn a Honda into what it isn't/wasn't meant to be.

[This message has been edited by Rubber Chicken (edited 19 May 2002).]

 

[jorligan]

If you look at the dyno curves for the BBSC with 4 lbs, there is actually less power until 5K than stock. It almost looks like the unit impedes air flow until 5K. This would explain the almost identical curves until 5K, there is actually no increased air flow until 5K. Does anyone know if there were boost guages hooked up during the testing?

Also the the #14, what's up?!? Does anyone out there have dyno info on a 3.2 CT setup?

Lastly, there is a lot of mention of a smaller pulley on the BBSC unit to bring on boost earlier and use a blow off valve, similar to a turbo. The problem is that the ECU would need to be reprogrammed. I am assuming that the ECU was reprogrammed to accomodate the larger injectors by varying the cycle duration to the boost pressure. Since the supercharger has a smooth predictable boost curve vs a turbo, you could simply vary the cycle duration per rpm vs a feedback system like a turbo. If you simply added a smaller pulley, you would get higher boost a low rpm but since your injector duty cycle would be short, you would be running lean.

When someone has a 3.2 BBSC with the latest software and hardware, please post your dyno info.

Thanks

Tim

 

[Yellow Rose]

Also the #14, what's up?!?

******************************

I'm #14. Can you be more specific with your question?

[This message has been edited by AndyVecsey (edited 20 May 2002).]

 

[cojones]

Originally posted by jorligan:
If you look at the dyno curves for the BBSC with 4 lbs, there is actually less power until 5K than stock.

Is this fixed in the production version BBSC ??

 

[jorligan]

My mistake, I was referring to #16. That car actually produced on 10 lbs more torque than a stock 3.2 motor despite full Comptech. I was wondering whether anyone knows what the true torque curve looks like for a 3.2 liter motor.

Tim

 

[JSG]

Originally posted by JSG:

1. When you want the kick of a SC, it is not happening at 2-4K, but at WOT. You will get that power very quickly.

Strange comment...I wasn't aware you couldn't be at WOT between 2-4k RPM...but i found it. It's under technical service bulliten #32342132 and saw the issue:
Please abstain from pushing the throttle to 100% between 2k and 4k RPM.


not.

2. We have heard a lot of theory here but very little real life testimonial about the production BBSC.

Do some research and you'll find MOST of everything that has been said is law not theory. Don't be so blind.


I was not very clear about the 2-4K rpm and the BBSC, but at least Rubber Chicken has a clue. If I am in the right gear and WOT, I will be into the power band of the BBSC very, very quickly (especially with my 4.55 R+P!) Yes, it might require a down-shift.
Yes, the other units seem to have more torque and power at the lower rpms, but I will be passing you very quickly (especially after the Intercooler is installed which is not available with the other units.)

Regarding testimonial....I would like to hear from someone who has actually driven a PRODUCTION BBSC, not mental masterbaters analyzing dyno charts (you will go blind!)

 

[ak]

How about SC NSX shootout at the track...say at NSXpo? Driven by someone without any bias towards any of the kit. Say...PD?!

 

[cojones]

Originally posted by ak:
How about SC NSX shootout at the track...say at NSXpo?

This would involve some sort of "time trial" event... which I believe several folks are considering as an optional entree at the coming NSXPO