We just replaced the timing belt on my 91 Si, which caused damage to the dampner.

Does the Unorthodox Crank pulley replace the dampner? Or does it bolt on to the dampner?

Jeff
Needs to know very quickly. Trying to get ready for a race this weekend.

 

Most aftermarket light weight pulleys have no dampener. I have read a lot of controversy on whether or no it is good to run it like this.

I however have decided to run a pulley without one. It is going on the car this weekend when I finish putting the rest of the car back together,

 

Thanks for the quick reply. I will try like crazy to find the Unorthodox pulley tomorrow, hopefully I will find one in stock locally.

Does anyone in, or near, San Diego have the Ultra R Unorthodox Crank pulley for a stock 91 Civic Si for sale?

Jeff

 

I've been thinking about running a lightweight pulley also, but I'm not really sure what is meant by the dampener. This is not a separate piece is it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FlyZlow &raquo;</TD></TR><TR><TD CLASS="quote">I've been thinking about running a lightweight pulley also, but I'm not really sure what is meant by the dampener. This is not a separate piece is it? </TD></TR></TABLE>

The stock pulley has a harmonic dampener that is part of the pulley.

I tried to do a good amount of research on them and the harmonic dampener is meant to absorb vibrations that would go through the crank. I have gotten a lot of support for both sides of the argument, but it seems like on a race engine it shouldn't be a big deal. If I have researched correctly the vibrations that can be damaging to the engine occur at a lower rpm and stop and go driving. We obviously don't do too much of that riving in our cars.

I take nor responsability for engines being ruined from these pulleys. This is some of the information I have read and thought I would pass it on. I have no clue if it is right, as I have not done any first hand research.

I have another aluminum sohc crank pulley that I am willing to sell. I have no need for it as it is still for the three belts and I now found one that is for just the alternator belt. Make an offer if anyone wants it.

 

Do a search as this is a common thread question and was covered just recently.

I think the last thread pretty universally agreed that the D16A6 CRX and EF Civic Sis did not have any rubber damper in their crank pulleys. I have certainly never seen any in the near dozen that I have owned. Some Honda models do and some don't. If it doesn't have a rubber damper as part of the stock crank pulley, then a good quality aftermarket pulley will be fine.

I have Unorthodox crank and alternator pulleys on my '88 CRX Si racecar in my garage.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX Lee &raquo;</TD></TR><TR><TD CLASS="quote">
I have Unorthodox crank and alternator pulleys on my '88 CRX Si racecar in my garage.</TD></TR></TABLE>

Uhh...Lee, we are talking about pulleys for cars that are actually *driven* once in awhile,not just garage queens!



--Andy

PS: I run a UR pulley on my STS Civic. When I opened the motor up at the end of last season, #1 and #2 main bearings were the *best* looking of the bunch, while 3 & 4 had quite a bit of wear. You'd expect the opposite if the pulley was a Bad Thing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Andy Hollis &raquo;</TD></TR><TR><TD CLASS="quote">Uhh...Lee, we are talking about pulleys for cars that are actually *driven* once in awhile,not just garage queens!



--Andy</TD></TR></TABLE>

OK, OK, that is valid. That is why I added the "...in the garge" comment so people wouldn't ask "So how do you like them?" for which I would reply "Without dust on them".

BTW, I have done more serious work in the last month to the car than in probably the last two years and hope to be ready for my March 26 lapping day. Please pray for me. Need some good karma.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX Lee &raquo;</TD></TR><TR><TD CLASS="quote">

Need some good karma.</TD></TR></TABLE>

j00 of all people shouldn't be worrying about good karma!

j00've done enough to keep j00 in good karma until the cows come home.

Andy,

What do you mean if the dampner was bad you'd expect the opposite? I'm not familiar with those little one cam motors

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by carl_aka_carlos &raquo;</TD></TR><TR><TD CLASS="quote">j00 of all people shouldn't be worrying about good karma!

j00've done enough to keep j00 in good karma until the cows come home.

Andy,

What do you mean if the dampner was bad you'd expect the opposite? I'm not familiar with those little one cam motors </TD></TR></TABLE>

#1 and #2 cyls are closest to the crank pulley. I.e. if there was a problem w/ vibrations affecting the bearings, you'd expect those 2 to get the worst of it.

I looked at my stock pulley today. That thing is heavy as ****! It did look like it had some sort of rubber thing inside the back of the pulley that I was assuming was the dampener, but now I'm not sure since Lee said his have never had them. Anyway, I think I'm sold on the lightweight one. My crank is balanced and people don't seem to think they do much harm in high-rpm track-only use.

Danny - where'd you find your alternator only pulley? I think that'd be the way to go, but if they're expensive or hard to find I might just buy yours.

- Scott

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FlyZlow &raquo;</TD></TR><TR><TD CLASS="quote">

Danny - where'd you find your alternator only pulley? I think that'd be the way to go, but if they're expensive or hard to find I might just buy yours.

- Scott</TD></TR></TABLE>

I don't want to say it, but yes I got it from SRD.

It was against my will, but they were the only ones.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FlyZlow &raquo;</TD></TR><TR><TD CLASS="quote">

#1 and #2 cyls are closest to the crank pulley. I.e. if there was a problem w/ vibrations affecting the bearings, you'd expect those 2 to get the worst of it.

I looked at my stock pulley today. That thing is heavy as ****! It did look like it had some sort of rubber thing inside the back of the pulley that I was assuming was the dampener, but now I'm not sure since Lee said his have never had them. Anyway, I think I'm sold on the lightweight one. My crank is balanced and people don't seem to think they do much harm in high-rpm track-only use.

Danny - where'd you find your alternator only pulley? I think that'd be the way to go, but if they're expensive or hard to find I might just buy yours.

- Scott</TD></TR></TABLE>

For torsional vibrations, the most flexible part of the shaft is the critical section. That would be #2 and #3 cylinders. Dampers only help mitigate the "bad" or resonant vibrations.

 

I've done a lot of research on it... long story short, use a harmonic balancer.

I predict someday Unorthodox is going to have a huge class action lawsuit brought against them regarding failed crankshafts, and enough expert witnesses/engineers will be called to make life very uncomfortable for them.

 

IIRC there was some one around this board that took off the belt part for the third belt. Like the CTR N1 crank pully

 

As far as the harmonic balancer is concerned, it may or may not be needed depending on 1) what RPM you tend to operate near and 2) what are the torsional resonant frequencies and the combustion frequencies (the actual frequencies that induce the resonance in the crankshaft). I haven't heard of any crankshaft failures in the mighty D16 but that doesnt' mean that it hasn't happened. I will use an Unorthodox pulley on my race motor, I need all the help I can get trying to keep pace.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Johnny Mac &raquo;</TD></TR><TR><TD CLASS="quote">As far as the harmonic balancer is concerned, it may or may not be needed depending on 1) what RPM you tend to operate near and 2) what are the torsional resonant frequencies and the combustion frequencies (the actual frequencies that induce the resonance in the crankshaft). I haven't heard of any crankshaft failures in the mighty D16 but that doesnt' mean that it hasn't happened. I will use an Unorthodox pulley on my race motor, I need all the help I can get trying to keep pace.</TD></TR></TABLE>

Yeah, that's pretty much my feeling too. Running a balanced crank and never sitting in stop and go traffic makes me thing that other things will break in my race motor long before I have a bearing failure caused by the vibrations from not having a harmonic balancer. This motor will probably only see a couple thousand miles at most in the span of it's lifetime and most of them will be spent in the upper 2.5k RPMs. Who knows though, I could be wrong.

- Scott, who's been wrong before ...

 

Update.

Was able to find a stock dampener to get me through this weekend

The car seems to be just fine, runs smooth and quiet. I wasn't able to find an Unorthodox pulley locally today, but I did get one ordered at a very good price. It was on my list of go-fast-goodies to buy, but it is just sooner than I planned.

Now if I can only get those sons of binches at Ground Control to send me my coil-over kit for my Koni's, 4 weeks and counting, and everyday they say it will go out tomorrow. The SD Tour is coming up fast and I need to get the car sorted and get some seat time. *Some* of the fastest STS Honda's will be there, should be one helluva battle.

Jeff


Modified by zo7vette at 9:09 PM 2/5/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zo7vette &raquo;</TD></TR><TR><TD CLASS="quote">Update.

The SD Tour is coming up fast and I need to get the car sorted and get some seat time. All the fast STS Honda's will be there, should be one helluva battle.

Jeff</TD></TR></TABLE>

I must be getting slower in my old age since I won't be there and "*all* of the fast STS Honda's" will be. Hey Ryan, I guess you are making the trip to CA? Or did you get slower, too?



--Andy

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FlyZlow &raquo;</TD></TR><TR><TD CLASS="quote">

Yeah, that's pretty much my feeling too. Running a balanced crank and never sitting in stop and go traffic makes me thing that other things will break in my race motor long before I have a bearing failure caused by the vibrations from not having a harmonic balancer. This motor will probably only see a couple thousand miles at most in the span of it's lifetime and most of them will be spent in the upper 2.5k RPMs. Who knows though, I could be wrong.

- Scott, who's been wrong before ...</TD></TR></TABLE>

Many people think the dampener balances the crank, no, it has nothing to do with that. It is *dampening* the high-frequency ringing (flexing) of the crank to filter out the power pulses.

You say this "other things will break in my race motor long before I have a bearing failure caused by the vibrations from not having a harmonic balancer."

And then this "most of them will be spent in the upper 2.5k RPMs."

What kind of race engine hardly sees 2.5krpm?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kb58 &raquo;</TD></TR><TR><TD CLASS="quote">What kind of race engine hardly sees 2.5krpm?</TD></TR></TABLE>

The "upper 2.5k RPM" range being from about 4.5k to 7k RPM in my car.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kb58 &raquo;</TD></TR><TR><TD CLASS="quote">Many people think the dampener balances the crank, no, it has nothing to do with that. It is *dampening* the high-frequency ringing (flexing) of the crank to filter out the power pulses.</TD></TR></TABLE>

I realize that it does nothing to balance the crank, however I thought that a balanced crank would need less dampening because it would not generate as much vibration. Admittedly, I have very little knowledge in this area and am very new to engine theory in general, but I'm curious how the dampener helps with flexing from the power pulses when the power pulses are applied to the crank directly through the piston -&gt; rod -&gt; rod bearing and the dampener is out on the end of the crank. I can see that it would help in not sending vibrations back that reach the end of the crank, but in a high revving motor, it seems like the power pulses would be so frequent that it would cancel out this effect. I know there must be some advantage (or else automotive engineers wouldn't build them that way), so I guess I'm just looking for a little enlightenment cause I obviously don't get it.

 

Think if the crank as a bell. In fact if you suspend one and hit it, it'll ring at its resonant frequency. At certain rpms, the power pulses hit at just the right time to make the ringing get bigger and bigger. Think of pushing someone on a swing. If you push just a little at just the right time, they go higher and higher. Same thing, and, worse case, the crank will physically ring so much it'll vibrate the bearings apart and the crank will eventually break. The rubber dampener filters out the ringing before it gets large enough to cause damage.

Of course it all depends at what frequencies/rpm it's run at and where it resonates... something only the factory knows.

 

Thanks for the explanation. Makes more sense to me now.

 

Used a CTR N1 Crank Pulley all year long on the HC car- No problems whatsoever.

 

Yeah I know, some people have them last a long time in various engines. But based on my research and reading, there does seem to be a connection between using a solid pulley and damaged bearings/cranks. So much so that I sold my UR pulley without ever using it...

[edit] Right, add failed oil pump gears to the list...


Modified by kb58 at 3:42 AM 2/6/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kb58 &raquo;</TD></TR><TR><TD CLASS="quote">Yeah I know, some people have them last a long time in various engines. But based on my research and reading, there does seem to be a connection between using a solid pulley and damaged bearings/cranks. So much so that I sold my UR pulley without ever using it...</TD></TR></TABLE>

It can also mess up the oil pump, which takes its input off the crank right near #1.

--Andy