Nashua_Night_Hawk

What do you think?

I expect that UR pullies showed a 13% improvement in HP/Torque all across the rpm range. I think that the 01 CLS-5 would be as fast as 03 CLS-6?

175 lbft * 1.13 = 197 lbft
200 HP * 1.13 = 226 HP

Do you agreee? Also, I have a CAI as a bonus

Assume a CAI would add 8WHP or 4%....
197 lbft * 1.04 = 205 lbft
226 HP * 1.04 = 235 HP

mattg

you mean a stock 6spd vs. a auto w/ pulleys only?

Nashua_Night_Hawk

Correct...

32vv1ll

the pullies alone give u 26 hp???

jimcol711

good question, seems unlikely considering the AEM pullies only do 2-3 hp..

Nashua_Night_Hawk

This is the dyno of the UR Ultra SS Prototype Kit on V6 Accord.



The CL-S (6-speed and 5-Auto) are scheduled for a dyno sometimes next week.

Red Rider

I'm anxious to see what the pulleys do.

mattg

no, the auto w/ pulleys only will not be as fast. didn't someone post a 14.3 or something w/ a stock 6 spd? i have i/h/e and my best run is 14.67. w/ my new tires i should be able to hit 14.50. i can't see the pulleys having more gains than i/h/e combined.

but, i also remember seeing a 6 speed posting 14.70's. and if the pulleys yield a 20hp, 20 tq. gain, i would say 14.70's are very possible. so

Nashua_Night_Hawk

With only a CAI , NGK Iridium plugs, 18" 235/40 Nitto I run 14.6s in 40-50 weather.

I would say simple math and physics predicts the following:

Since Accrleration is directly propotional to the square root of the Accelaration force, a 13% improvement in torque/HP all across rpm means ...
that the 1/4 time should be reduced by sqrt( 13%)
or 3.6% so 96.4 % of 14.6s is 14s...

I will be happy to hit 14.2 sec in th 1/4 mile

BTW, another CLS-5AT with h/i/e run 14.2s at 99 MPH!

mattg

if you are shootin for 14.20's, i should be able to hit 14.00's or 14.10's.

my snow tires really hindered my 60' times, couldn't break 'em loose at all. a little bit of wheelspin off the launch helps to get the rpm's up. i'll know more on the 15th, import drags.

i'm so glad i'll have a new mod by then.

EricL

Ok, compare mods in same weather

I don't have a clue where you got the acceleration is directly related to the square root of the acceleration force.

F = ma and a = F/m and F is equiv to Torque at wheels. The relationship between the torque (force) and acceleration is "linear" and correlated with the Force (torque at the tire contact).

Velocity is : v = a t (using uniform acceleration)
Change in distance with uniform velocity is: d = v * t
and v = a * t. Integrate (a*t) with respect to t and you get:

Distance is: d = 1/2 * a * t^2.

Now solve for t with d = 1320 feet, so t^2 = d*2/a = 1320*2/a

Quarter mile time (t) = 4*sqrt(165)/sqrt(a) = 51.380/sqrt(a).

Time to test the equation with a 1G constant accel (1 gear/flat torque) = 32ft/sec^2 (substitute 32ft/sec^2) for a! (use: a = 32 * 1, 32 * 0.5, 32 * 0.4, and so on)
Time @ 1G = 9.0827 sec
Time @ .5G = 12.845 sec
Time @ .4G = 14.361 sec (approx average 6-speed/Mike’s with around 200 lb-ft of TQ)
Time @ .39G = 14.544 sec
Time @ .35G = 15.353 sec (take the .4G run and factor by 175 lb-ft/200 lb-ft (stock vs. Mike’s or 6-speed)

(THIS IS FAR TOO SIMPLE an APPROACH!!!!!!)

Now, the acceleration is going to be related to the gearing and the time and distance in each gear is going to be different. For now, you could assume a “flat torque” curve.
The first gear acceleration is probably closer to .6G, second gear .4G, and third near .3G (I didn’t didn’t use the gear ratios for the calcs – please feel free based on a GTECH reading on a car in second gear.)


PULLEY GAIN VS. GEAR AND WHY THIS GETS MORE INVOLVED:

1. So, perhaps you meant the time to distance is dependent on the sqrt of acceleration (and that presumes it is constant -- it's not!)

2. The acceleration in each gear is related to torque and the inertial loads and relationships (with no pulleys) changes in each gear.

3. The change in gain via the lightened pulley changes per with each gear ratio. When I have some time, I'll try to dump some pictures of simulation modules with a mass on one side of a gearbox with varying gearbox ratios.

4. IF YOU WERE USING a non-inertial dyno, you would see no gains.

5. If you change the sweep speed with a non-Dynojet dyno the gains would change

6. The "measured"/"implied" HP pulley gains increase with lower gear (1st) and decrease with higher gear (4th)

For reference: you can expect more gains (than shown in the dyno) in first gear than in 2nd and so on. Since the dynos are done in 3rd on the CLS and the UR pulley dyno was done in third for the V6Accord (tell me if I’m wrong), the expected percent improvement should correlate to the 3rd gear dyno pull when accelerating in 3rd gear (within limits); the "perceived" acceleration gain in 2nd would be greater, and in 1st would be greatest. As you go the other way toward 4th and 5th gear, the advantage/gain (from the pulleys) lessens.

Finally, as the car moves up against the wind drag (related by velocity^2), the pulleys will show less and less influence. I don’t know if I mentioned this, but there would be probably be no gain in top speed with pulleys (with top-speed limiter removed)

I did this as quickly as possible and there are some ways short of a time-step simulation to get a bit closer, but….



I think you might need some other goodies if your not running in very cold temps.

mattg

you must admit, this is the kind of improvement the cl-s needs. especially one w/ i/h/e running the 1/4. the sooner we get in to vtec the better.

Nashua_Night_Hawk

Thank Eric for long math/physics elaboration, You are correct, It should have read:
And I assumed average linear acceleration to get a rough estimate. So, if math predict 14s flat, 14.2s is close enough to be realistic.

But I agree there are a lot of variables in the play.

spiroh

I wouldnt draw any conclusions, until we see the dyno done on our cars. From the looks of it, they are going to do the dyno on a 6speed anyways. If these pulleys truly give you that much of an improvement I'm game.

Roell

So, let me summarize.

We are saying that a CLS with pulleys, will be able to run a 14.2?

???
Am I reading this right?

Brian

EricL

I wouldn't draw those conclusions just yet....

Just the difference in transmissions between an CLS and an Accord could alter the change in rotational mass and have a significant impact on the gain shown on a Dynojet...

So, maybe, maybe not -- I doubt it (at least a auto CLS with pulleys alone).

(6-speed with pulleys, probably... who knows -- it will become clear very soon).

EricL

Yes, if the vibration is not an issue (or near undetectable) and the dyno plays out similar to the Accord, I will be getting them.

NOVAwhiteTypeS

http://www.acura-cl.com/forums/showt...threadid=71410

i/h/e almost dead even w/ a stock 6 speed except for K&N and no resonator

EricL

AS a note, the acceleration without the headers is actually lower in the 5- to 7-K zone.

It seems that the car accelerates "better" from 5k to 7k (VTEC range), but the acceleration is related to the torque.

Here is the picture of the 6-speed manual:



The torque is flat and highest from 3K to 5K RPM and goes down from there. That means less acceleration in VTEC land!

When a header and CAI is added to the auto CLS, there is a slight torque peak near 6K rpm, but goes down quickly from there.

Strange, it "seems" that its going faster in the VTEC range, but I measured the "instant accel" with my GTECH (when stock) and the highest acceleration was NOT in the 5,500 to 7000 rpm range!

mattg

that seems hard to believe using the seat of the pants meter. but i see what you're saying. i hope the pulleys will help the 3.2 to spool up quicker off the line.

Infamuz

We are all waiting patiently for Nashua's Pulley installation. Hope the gains are good.

Nashua_Night_Hawk

I called off the installation Appointement, as you know by now, the CLS and Accord have different Alt pulley, so till I get a CLS specific Alt pulley... no new feedback... that sucks...

3.2cl-s

Just because there is a decrease in torque, doesn't mean that the car doesn't accelerate as fast or faster.............hp is still going up, in any race you can tell that below 5k rpms most cars can stay even with you, but once you hit vtec you start to pull.

SiGGy

14.2 is what im shooting for.

Hopefully a small shot with ZEX would put me close to a high 13

mattg

with pulleys only? good luck.

SiGGy

no with H/I/E/P

Nashua_Night_Hawk

we will see... Just wait till I get the alt pulley..., installtion, then track, baby...!

mattg

that sounds more like it. you are getting all these mods at once? i don't see any in your sig.

SiGGy

I have the comptech exhaust already, just haven't bolted it on.

I'm pickup up the headers/CAI on saturday. And everything accept the pullys will be installed by next friday.

I want to see some results for the pullys before I order them. If not, I'm thinking a 50shot with the ZEX system mabye. Am I on crack for even thinking of using it? I think I'll definetly hold off on the ZEX system until the ICE box and other mod's surface...

The install for ZEX is so simple.

EricL

The acceleration follows the torque curve. I've measured it.

The reason the CLS pulls ahead of a lot of cars over 5K, is a result of their torque falling-off faster than that of the CLS. YOU ARE ACTUALLY ACCELERATING at a lower rate over 5K (unless you have headers). IN the case of the headers the peak torque is around 6k+ RPM and that is where the peak acceleration shows up.

I didn't just "make this up"...

The torque that ends up at the rear wheels is a function of the torque at the engine multiplied by the gear ratio. Lower gear means more torque at the wheels; higher gear, less torque at the wheels. The torque curve you see on your dyno correlates to the acceleration.