Im sure some of you have seen that the new underdrive pullies are out for the accord, and they fit our cars too. The accord put 20hp to the wheels, and was told our car should produce about the same power. Well, they just came out and i went ahead and joined the GB on accordv6.com, does anybody think i wasted my money, should i expect these kinds of gains?

 

Didn't someone post that pullies increase power but at the expense of torque, some power steering and stuff...?

 

On Dyno it showed increased torque and HP all across the rpm range, much like the RES!

So far estimated cost:
$274.63 + ( $10 shippping charges)
$15-$25 for TopQuality Belts
$120 for the installation
============
Total is estimated at $425 (max)

 

I'll let one of the members buy them first and give us a report before I buy. But if the Dyno is true then this could be the best bang for the buck mod.

 

You could save $120 if you installed them yourself!!!!!!!!!!

 

Yes of course... but how you are gona untorque a nut torqued to 180lbft!!! ( crank pulley )... Nevermind torquing it back to spec.... You have to have a special Crank pulley holder/puller...

I would pay $100 rather then fook up somthing... I am paying a Master Tech to do it, not a poor guy like myself

 

i was told it is a difficult install, you need a high powered impact gun to loosen the crank pulley. i'm having mine done at the dealer too.

and i believe the crank pulley is the only underdriven pulley. the other pulleys are just lighter, so no effect on them whatsoever, exept they spin w/ less resistance.

we will know much more in a week and a half.

 

no the undrive of the crank undrives everything else but not much....you just wouldnt wanna add the crank to aems to undrive pulleys that are already undriven....


nashau 180 lb.ft. no shit????wow i thought i was gonna do this myself

 

I don't really know what to expect from this Mod.... I really hope the claims are true though... that would be awesome band vs. $$

Hell.. it works on a supercharger....

Good Luck to all the Guinea Pigs !!

DOM

 

The gains -- due to weight loss -- are different depending on the "inertial" mass of the engine's rotating parts.

It might be advisable to see a dyno of a CLS/TLS to see how much the gains are on OUR car.

If they really are 8lbs lighter (someone mentioned this -- but I don't know about this figure) they could help fuel economy and acceleration.

IMO, I would have the dealer do it.

Previous link about "effect" of weight loss at various places in a "car". (Note: all of this stuff is a bit oversimplified. [where and how the weight is removed is important])

Link of interest:

http://www.acura-cl.com/forums/showt...ght=Rotational

 

6 lb.s...its what i think i read at AV6 i say think because it was like 6 + pages and im not going back to scim through and confirm...

 

What was the peak torque/hp increase? I'd love to see that dyno... Anyone with a scan?

 

Here, from an ealier thread posted by Nashua:



link to that thread: http://www.acura-cl.com/forums/showt...threadid=69645

 

I stand corrected... Your quote from the previous thread:


"i heard 6 lb. savings wow...6 pounds....not sure if thats true and it could be 6 from the whole set...the AEM doesnt use the crank at all...i think this is where most of the gains are coming from..."

 

erik ...you gotta admit...seeing that dyno sure make the prospects of big gains for our car very interesting...the more mods you have the more they should exploit them ... i probablly wont dyno right away ,but ill go to the track where ive established a strong 9.5 base if i run a 9.4 in the heat ,we'll know they're for real...

 

1. Is that Dyno impressive – yes…

2. Based on the info on the UR site, and their claim of NO breakage every caused by their parts, it looks like a good possibility/mod. option.

3. The rotational inertia stuff can get a bit confused... I've got some simulation models for inertial loads on either side of a gearbox with an electric motor driving the "system" (I can simulate our engine, to a point, but ...). The largest gains -- from a reduced rotational weight on the input side of a "transmission" -- come when the engine is spinning much faster than the "car" “translation” speed and/or wheels, tires, driveshafts, brake disks, and other parts that are driven at speeds that depend on the current gear ratio. (The lower the gear [e.g. 1st gear vs. 5th gear] the more the "effect" is felt from reduced mass on the engine. For example, if I put the car on a dyno that only measured static power, there would be no visible gain from the pulley (and no change in top speed [even without the top speed limiter]). A Dynojet dyno run in 5th gear would show a smaller HP gain – from the pulleys -- than one done in fourth gear. There would be a "reduction" in the "virtual HP/TQ gains" shown by the pulleys (or any other weight/mass loss on the engine side of the gearbox). i

"The Probem" with all of this is NOT that the pulleys will give a gain (they will -- I'm sure of it). The question is how much additional HP/TQ for our car. The swap will probably increase "perceived" engine vibrations (just like a lightened flywheel). There is a good reason manufacturer's are now using dual-mass flywheels (low vibration and good damping combined with lower inertial loads). The greater pulley mass helps damps engine pulses (it's not a turbine). The other issue is the posting of the dynos as "absolutes" and as pointed out in earlier threads, there was a lot of time that transpired from pre-pulley test to post-pulley test. Finally, I doubt that the inertial load of the CLS/TLS transmission (and related parts) is the same as the Accord's.

Having a member, like you, actually TEST the unit on an auto tranny CLS/TLS, would go along way to getting them on more cars (especially mine). I would like to see an impression of any changes in vibration and then 1/4-mile and/or dyno runs (before and after).



Excerpt/quote from UR’s site:

”The fact is, on todays [sic] late model cars the factory crank pulley is designed to reduce NVH (noise / vibration / harshness), which does not affect crankshaft or bearing life. These are noises and vibrations from the engine compartment that may travel into the cabin of the vehicle when the engine is running and the stock crank pulley is used to reduce NVH for the occupants (similar to the use of resonators in the intake to quiet intake noise)…”

(Obviously, if a person only purchased the car for performance alone, this wouldn’t be an issue.)

 

I am planning on taking my car to the track after the UR pullies are installed. My last best was 14.6s I am shooting for 14.2s with those UR pulleys

I need some 40-50 weather... :P

 

Definitly need those before and after times WITH temps...


(I'd hate to see a 'comparo" with one run at 85-degrees and the other at 40-degrees...)

 

I will be gettin the pullies next week, and hopefully by the end of the week i will have a before and after dyno..........i can't wait, just hoping i get some good #'s, as im sure you guys are too.

 

It's called a cheater bar and gettin leverage on the nut Longer the bar, the less force you have to exert. But yes, not a recommended self-install, especially for most of the people on this board :P

 

actually, it's called a 1/2 inch impact gun. the tool of choice for pulley removal.

 

As stated earlier the service manual specifically state of not using a impact gun or impact wrench...

I believe 99% of problems with crank pullyes is due to non-factory isnatllation and removal procedures. If you do not do the installatioon and removal as stated by the service maunal you are asured to mess up your engine.

When I will go to do the installation, I will make sure to have photocopies of the installatioon and removal procedures handed to the Mech before he starts the instalation. Just be on the safe side.

 

oops. maybe i are wrong.

 

i thought that was called a breaker bar??

sidemarker

 

i agree if you can get a impact down there, that will be the perfect tool to remove the bolt

BUT

installing is a different procedure

you might want to slowly tighten it with a socket

then torque it with a torque wrench...


sidemarker

 

A cheater bar is what you add to your ratchet to make it longer. Can be a piece of pipe or anything. I personally have a jack handle that I use to remove stubborn bolts. A breaker bar is basically a long ratchet but with no ratcheting action. So you could add a cheater bar to your breaker bar to get even more leverage.

Here's an example of a cheater bar when I was pushing out a bushing. You can see the head of the regular 3/8" ratchet: