PyroProblem

The magical voodoo of engine harmonics and all that 1st and 2nd order mumbo jumbo has led me to the conclusion that if you start messing with the physics inside the engine, a better crank pulley/damper is a really good idea.
I look at it like this.
The further you get away from the stock rotating assembly, the less effective the stock pulley becomes. That little ring of rubber you see on your factory pulley is tuned for your stock internal engine.
Bigger bore, larger pistons, different rods, larger strokes, all this weight changing around, etc all affect harmonics to the point the stock pulley can't absorb the new/increased/frequency range. I'm sure clutch and flywheel also play a small role..
That's when **** goes bad.

Ever hear or read about those guys who flywheel bolts come loose mysteriously over and over? Or crank pulleys that come loose at the end of a run? too much vibration not being absorbed/cancelled out.
Harmonic demons at work.

PyroProblem

Hah. Just realized I repeated what unusual said. Lol. Long day...

PyroProblem

How long after the unorthodox pulley install till you started having problems? Main bearings? Which one?
Makes you wonder why the factory specs a little more oil clearance on the center main. Crank flex perhaps...

wunfstgsr

Very well said. Corvettes are known for crank pulleys coming loose.

It was about 3 weaks i want to say, i really beet on that setup. it made 198 WHP on a mustang dyno and was making good power for what it had back then. It was a street and drag integra but once i got into changing the crank pulley it had one hell of a fast throtle responce like neck snapping quick. I believe the crank walked to much and the one or two of the main bearings where gone not sure which ones. Me and my tech tore the engine down and we came to the conclusion. This was a on a bone stock short block. The unothadox is just all metal weighed very very light as well...

TracerAcer2.2L

The flywheel also acts as a "damper" and is balanced. It absorbs vibration as well. The crank pulley is nowhere near that large or heavy so it needs the rubber

PyroProblem

Which could mean that running a lighter flywheel makes a better crank pulley/harmonic balancer/crank damper even more important.

I ran a "lightweight race pulley" once. It ruined my crankshaft. Worked loose and chewed up the keyway. lesson learned lol.

TracerAcer2.2L

Yikes

Yeah I had a UR underdrive pulley, didn't even have the chance to run it on my motor. I did some more research and changed it out for a Euro-R pulley real quick

PyroProblem

The rubber band in the stock pulley is also said to help with engine" pulses" to the belt driven accessories. Sorta to cushion the shock of the power stroke to your a.c. compressor and ps pump.
Sometimes you can see the belts deflect a lot at different rpms. Sometimes you see the deflection Increase and decrease as you go up in rpm. Weird stuff it is.

PyroProblem

Not all the CTRs have the solid pulley your describing (known as the N1 pulley) . I running a stock ctr right now and it the crank pulley has the extra ribs for AC/PS. I haven't looked lately but I'm 99% sure it has the rubber ring/damper. Idk if the N1 pulley was an option for the ctr or just a factory race part for off road use only.

TracerAcer2.2L

I have heard that before, about the cushioning for accessories. Proponents of lightweight pullies say that that's all the rubber ring is for, but being in the H series crowd you know that is simply not true

cksnah252

Shoot i didnt even know you guys were still responding to this! So what you guys think? ATI/FLUIDDAMPR over what I have now (USDM ITR PULLEY)?

TracerAcer2.2L

Ok I'll break it down once more.

First off, the ITR pulley is a damper and is completely safe.

Now,
ATI damper: $350+, plus $50-75 for required future rebuilds. Only very minimal HP gains, only most effective on very high HP racing motors for the cost.

Skunk2 intake mani/ TB combo: TB's just as good as Skunk2 can be had for half the cost, and a Skunk2 manifold can probably be found used. As wunfstgsr said, great gains will be realized from this combo. Very high HP to cost ratio.

Custom header: IMHO, a mod as good as or better than the manifold/throttle body combo, considering your current exhaust header. Cost may be $900-1,200, but gains up to 15-18 HP may be realized (based off what I've seen of dyno graphs of SMSP headers. I know a couple other header builders that make similar power)

Based on this info you should be able to make an educated decision

spAdam

iTrader: (1)

I don't really consider a damper to be a power-building part though. More like a reliability & longevity building part. If you're just looking to make a few extra HP, put that $350 toward a better header or something.

But the damper is still a great investment, IMO. I would personally prefer the Fluidampr just because it doesn't require rebuilding, but it only comes in the 5.9" B20 size... at least in the 3 row configuration. No matter which one you decide on, it should be new. If you're still using the one that came on the motor, it's at least fifteen years old now and the rubber is junk.

OneBadTurboCRV

There is a lot of funny stuff in this thread but I have to disagree. I have never personally liked the idea of fluid inside a dampener for various reasons... Anyways here is something to explain the differences between the 3 types of dampener (although the torsion one isn't found in the Honda world that I am aware of).

ATI, Fluidampr and TCI Clear Up Damper Confusion - StangTV

For multiple Honda specific horror stories you can look to a single thread even though there are many more accounts of this. ATI is the preferred dampener of most all racers that are serious. In any event, a new balancer is preferred no matter which route you go.

https://honda-tech.com/drag-racing-3...g-off-3146699/

TracerAcer2.2L

That was my point

Most serious racers do use ATI. I'm wondering though, if it's just because most don't understand the technology behind Fuidampr. ATI is much easier to wrap your head around

unusual71

All good, this thread has attracted some long time users...

cksnah252

Alright guys thanks for all your help! ULTRA MANIFOLD AND 74mm TB HERE I COME! /thread

wunfstgsr

Look into the spacer for the ultra manifold a member just fabed up $70 shipped! I'm getting one soon for testing.

TracerAcer2.2L

Wasn't skunk2 supposed to come out with their own spacers for it?

wunfstgsr

not yet.

Tim2179

iTrader: (2)

Stock HP levels are fine for a stock damper. If you are making considerably more power, than an ATI Damper is a great investment. You don't want to spend thousands on an engine build, only to have it fail by using a lightened pulley.

Some of the weights listed on ATI's website/catalog show the weight of the damper assembly - but this # doesn't always include the weight of the hub. Why? Because ATI offers hubs in either steel or aluminum. The steel ones average about 2.4 lbs. and the aluminum ones are a little bit lighter (although not always a better choice).

A rebuild schedule on an ATI damper on an engine making less than 300 HP would be once every 10 years at the earliest. These dampers are running on engines with sometimes upwards of 2000 HP and those are the ones that require a more frequent rebuild schedule - as do those engines themselves.