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Appears to be a harmonic dampener as well.
Right. Now that you say it, that's what it is; should have see it before. Maybe a PO had a damper from an AT car and put it on even though he wasn't running an AT.

BTW, Bob: Can you give me contact info for the older aftermarket sources for the billet pulleys, if any are still selling? This will be going on a conversion to 2.2l, and I think something lighter than the damper would be better.
 

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Über Genius
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Where can you get this pulley?

Any idea if there are double pulleys that also have harmonic dampeners?
Well, the answer tot he first part is tricky.

I own the design of it. There was a group buy, a year and a half ago. I allowed my design to be used for that group buy.
I'd be happy to finance another group buy if the original coordinator doesn't want to do it, assuming he'd allow me to use his contact info.

The second part is, no, there's no double pulley with harmonic balancer on it. I have no desire to design such an animal either. I've found the CIH well balanced enough to not need one.
 
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Opeler
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Well, the answer tot he first part is tricky.

I own the design of it. There was a group buy, a year and a half ago. I allowed my design to be used for that group buy.
I'd be happy to finance another group buy if the original coordinator doesn't want to do it, assuming he'd allow me to use his contact info.

The second part is, no, there's no double pulley with harmonic balancer on it. I have no desire to design such an animal either. I've found the CIH well balanced enough to not need one.
Well, if one were to become available I'd like to buy one. Looking to install A/C in my car at some point...
 

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Opel Rallier since 1977
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no dampener req. very little balance work for four cyl. opposing design of the throws.
Be aware: Damper rings are NOT put on crank pulleys for engine balance! The ring MAY be imbalanced on a given engine to provide external balance weight, but that is a separate design function, and balance is NOT the primary reason for a damper ring.

They are there to damp out internal, torsional crankshaft vibrations. These vibrations are completely inside the crank system (crank, pulley, damper, and flywheel or flexplate + TC), and are of a twisting nature; i.e., the front and rear parts rotate back and forth a minute amount at very high frequency relative to each other. The frequency of these internal vibrations are typically in the range of 6000-8000 cycles per second. All cranks have this but the longer stroke engines are more likely to get these vibrations excited to a damaging level. The damper literally damps these vibrations out, or at least keeps them to a small level.

If unchecked in certain engines, or induced by other modifications to the crank system, these vibrations will consistently break crankshafts.

That is the one concern I have over the solid pulley above, and any heavy cast pulley put on a crank designed for a light pulley: The rotational weight/mass of that whole assembly modifies the crank assembly's vibration frequency and may put the natural vibration frequency of the assembly into play. Only some time and use of them and the experience of the cranks being fine or breaking will tell the tale for us guys in hot-rod land without the design abilities to predict it. This probably OK but you never know for sure until enough use shows the result.

Over in V8 land, one mfr (Moroso IIRC) made some solid hub pullies for small block Mopars for a while; the cranks using those would tend to break. That crank design came with a damper from the factory, so in that case, it was pretty obviously asking for trouble to eliminate the damper.
 

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Opel Key Master
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We make those pulleys, and have done two group buys for them, unfortunately the last group buy when I was ordering them was (zero) I still ordered 10. You have a 2.2 already, so do you not have an original 2.2 double groove pulley? They have a harmonic balancer made in to them. I have one or two of those pulleys, and they will work with our air conditioning kit. I try when someone is using a 2.2 to use the original pulleys, some stated you don't need them.
 

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Opeler
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We make those pulleys, and have done two group buys for them, unfortunately the last group buy when I was ordering them was (zero) I still ordered 10. You have a 2.2 already, so do you not have an original 2.2 double groove pulley? They have a harmonic balancer made in to them. I have one or two of those pulleys, and they will work with our air conditioning kit. I try when someone is using a 2.2 to use the original pulleys, some stated you don't need them.
When I bought the 2.2 engine from OGTS years ago, I just transferred over the original 1.9 pulley. I noticed a vibration issue and called Gil, he said that 2.2 & 2.4 motors needed harmonic dampeners for the reasons stated above. So I was sent a single groove harmonic dampener pulley, which has been on the car ever since without issue.
 

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Opel Rallier since 1977
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When I bought the 2.2 engine from OGTS years ago, I just transferred over the original 1.9 pulley. I noticed a vibration issue and called Gil, he said that 2.2 & 2.4 motors needed harmonic dampeners for the reasons stated above. So I was sent a single groove harmonic dampener pulley, which has been on the car ever since without issue.
I sincerely hope no one minds me putting my 2 cents worth again on this. IMHO, it is worthwhile in this matter IMHO to google 'harmonic damper function'. FWIW..... you cannot feel the crank vibrations that a damper damps; they are waaay up in a high frequency range, like 6000-8000 Hz. The engine vibrations we feel in out butts are at a far, far lower frequency. If there was some obvious physical imbalance to your replacement pulley (like a bunch of holes drilled on one side), then that is what solved your vibration.

A given damper CAN have both functions designed in (to act as both a damper AND an external balance weight) but it will have an obvious physical imbalance, or have certain mass properties (not a damping property), if it is intended to be part of the engine balance to cure 'butt-feelable' vibrations.
 

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When I bought the 2.2 engine from OGTS years ago, I just transferred over the original 1.9 pulley. I noticed a vibration issue and called Gil, he said that 2.2 & 2.4 motors needed harmonic dampeners for the reasons stated above. So I was sent a single groove harmonic dampener pulley, which has been on the car ever since without issue.
This surprises me as I have retrofitted custom 3” aluminum crank pulleys to 2.2’s and spun them over 9000 rpms and they were always smooth as silk. No harmonic balancer.

However all components were always balanced beyond factory specs. Crank/rods/pistons/flywheel.
 

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Opel Rallier since 1977
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This surprises me as I have retrofitted custom 3” aluminum crank pulleys to 2.2’s and spun them over 9000 rpms and they were always smooth as silk. No harmonic balancer.

However all components were always balanced beyond factory specs. Crank/rods/pistons/flywheel.
Not surprised that they are smooth as silk, Bob. A balanced damper does not provide any balance contribution to the engine balance (i.e., 'butt-feelable' engine vibrations).

But that is a separate matter from internal torsional crank vibrations that a damper is designed to keep under control. I cannot say what any particular 2.2L solid pullies have done in that matter, but crank breakage when replacing dampers with solid pullies is a real issue that does occur at times. It's not guaranteed to happen, and usually takes some operating time to happen if it does; but just because some cranks of a particular type survive without a damper, does not mean all cranks of that type will do so. The engine design engineers decided that the 2.2L crank and engine design was such that the internal crank vibrations could be an issue so included a damper for production. Maybe they over-reacted and a damper function is not really need for the 2.2L? I dunno....

FWIW (And you can stop reading if you are bored with my comments on this! LOL)..... Everybody here needs to realize that crank damping and engine balance are 2 entirely different matters. This all gets confused by the term 'harmonic balancer' that gets thrown around. If the pulley or damper is balanced by itself, then it does nothing to contribute to engine balance. A pulley or damper has to be imbalanced in a specified way to be a part of the engine balance.

Damping is a separate design issue, and typically involves a 2 part damper/pulley, with the outer ring connected to the hub with an elastomer ring. There are other damper design types (look up 'Fluidamper'), but this is the typical production design; it's cheap!
 

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This surprises me as I have retrofitted custom 3” aluminum crank pulleys to 2.2’s and spun them over 9000 rpms and they were always smooth as silk. No harmonic balancer.

However all components were always balanced beyond factory specs. Crank/rods/pistons/flywheel.
Not surprised that they are smooth as silk, Bob. A balanced damper does not provide any balance contribution to the engine balance (i.e., 'butt-feelable' engine vibrations).

But that is a separate matter from internal torsional crank vibrations that a damper is designed to keep under control. I cannot say what any particular 2.2L solid pullies have done in that matter, but crank breakage when replacing dampers with solid pullies is a real issue that does occur at times. It's not guaranteed to happen, and usually takes some operating time to happen if it does; but just because some cranks of a particular type survive without a damper, does not mean all cranks of that type will do so. The engine design engineers decided that the 2.2L crank and engine design was such that the internal crank vibrations could be an issue so included a damper for production. Maybe they over-reacted and a damper function is not really need for the 2.2L? I dunno....

FWIW (And you can stop reading if you are bored with my comments on this! LOL)..... Everybody here needs to realize that crank damping and engine balance are 2 entirely different matters. This all gets confused by the term 'harmonic balancer' that gets thrown around. If the pulley or damper is balanced by itself, then it does nothing to contribute to engine balance. A pulley or damper has to be imbalanced in a specified way to be a part of the engine balance.

Damping is a separate design issue, and typically involves a 2 part damper/pulley, with the outer ring connected to the hub with an elastomer ring. There are other damper design types (look up 'Fluidamper'), but this is the typical production design; it's cheap!
Mark, I’m familiar with the purpose of a harmonic dampener.

But even with years of use on numerous 2.2 engines I’ve never seen issues that harmonics would normally produce, such as loosened/fretting flywheel mounting faces, fretting main caps, or abnormal bearing wear.

I can’t say I’ve run the 2.4’s without dampeners, but those engines already have an 8-counterweight crank which throws another curve into the mix.
 

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Opel Rallier since 1977
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Thanks, and that is good. I assume it is correct that the 2.2's had dampers from the factory? (I dont know 2.2's....) It may well be that 2.2's don't have all that much internal high frequency vibration in the cranks. If everyone came back and said that they have never seen a 2.2 crank break with solid pullies, than that would settle that. The designers may just have been worried over nothing or they were looking at common parts with 2.4's. But, this problem HAS cropped up with other engine types.

FWIW, I would not expect main cap fretting (cap walk) with this issue; actually, I should say I have not heard of them going together before. I cannot say on bearing wear. These vibrations are not radial in nature... they are torsional. That is why these dampers are designed as they are... they are designed absorb/manage torsional movements, not radial movements. And fretting at the flywheel or damper/pulley hub would occur only if they were not locked down with sufficient clamping force. So I don't know if a lack of that says anything one way or the other. (BTW: What IS the torque on the front damper bolt on a 2.2L or 2.4L?)
 

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Ok read this thread and think it is most relevant to my issue. I removed my pully to make it easier to get the last water pump bolt out. I then bumped the starter and unknowingly kicked out the distributor gear?? Besides bending the pulley on the way out, I'm out of time now. My 2 questions are Where can I get a new pulley and how do I get back in time without taking off the timing chain cover to see the cam timing mark?
73 gt 1.9
 

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Opeler
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Ok read this thread and think it is most relevant to my issue. I removed my pully to make it easier to get the last water pump bolt out. I then bumped the starter and unknowingly kicked out the distributor gear?? Besides bending the pulley on the way out, I'm out of time now. My 2 questions are Where can I get a new pulley and how do I get back in time without taking off the timing chain cover to see the cam timing mark?
73 gt 1.9
Give Opel GT Source a call. They should be able to help you with getting a new pulley and with some advice.

Good luck
 

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Just Some Dude in Jersey
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As I recall, it's:

pulley - toothed timing chain gear - angled gear for dizzy/oil/fuel pump - bearings/rods

If I understand you correctly, you're saying that your dizzy timing angled gear slipped far enough forward to disengage the dizzy and you've lost ignition timing?

I can't imagine that the timing chain toothed gear could slide forward enough to disengage. This would be piston/valve timing.

So it sounds like you just need to do a basic dizzy reinstall. You only need to remove the valve cover. If you're clever, you might not even need to do that.


Others can fill you in on the process.....


:veryhappy
 
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