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TR2/3/3A Harmonic Balancer - narrow belt pulley

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croz

croz

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Does anyone know of a replacement or aftermarket harmonic balanced pulley that will fit a narrow belt conversion and all the components for the fan?
I have changed over to a narrow belt with alternator, and the replacement lower pulley is solid aluminum. Although all moving parts were balanced when the engine was rebuilt there are still some vibrations that could be related to the lack of the stock harmonic balanced pulley.
Cheers and Merry Christmas to all.
Steve
 
croz said:
related to the lack of the stock harmonic balanced pulley.
Click to expand...
Huh? The stock pulley was pressed steel, no dampening or balancing involved.
 
croz said:
Does anyone know of a replacement or aftermarket harmonic balanced pulley that will fit a narrow belt conversion and all the components for the fan?
I have changed over to a narrow belt with alternator, and the replacement lower pulley is solid aluminum...
Click to expand...

There is a narrow belt conversion kit available that has a harmonic dampener for the crank pulley. However, you can't use the original engine driven fan, and must install an electric fan. I haven't seen any that will accommodate the original fan.

BTW, the kits with the harmonic dampener are available from British Frame & Engine (where I got mine from) and Moss.

Here's the kit from Moss...https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=52039

BF&E also has an optional (read way more expensive) harmonic dampener if you're into pushing your engine into really high revs. :smile-new:
 
Hello Randal, Thanks for the information. 8 years into this car and I'm still learning...

Hello Art, Thanks for your links. I'd like to stay away from an electric fan if at all possible, and with Randal's news it looks like I'll just keep my current setup. I will however change the motor mounts from uprated back to stock.

Cheers,
Steve
 
Does your solid aluminum pulley have the extension for the fan mount? I've never seen one that does. Usually, the whole point is better performance, and the crank-mounted fan is seen by most as wasting power. The nice thing about electric fans is that they only use power when it is needed, which isn't very often and usually not when you want the power for performance.
 
I had designed a serpentine pulley system for a TR6. I paid for the rights to use the SAE specs for the pulley grooves. The damper was designed to match the original damper's dynamics for centrifugal conditions and kinetics. The hub and other pulleys are aluminum. And the belt to be used was decided on after consulting with Gates and other companies engineers. This is a CAD/CAM/ENG solid model of it.

I am sure something similar could be done for the TR3/TR4 engines if there was an original available. However, it would need to be destroyed.

sys.jpg
 
Were you able to measure the difference in actual power loss?
 
Randall, I never did make it. Bought a Midget in pieces and got involved in a complete restoration that got a little complicated. https://smithtr6.com/bearings.htm Finally getting back to the TR6 and starting in the rear of the car. Probably be a year or so before moving to the pulleys. The reason I did this project was to be able to use a belt that was easier to fit through between the damper and cross frame. There would be some power benefit due to the efficiency of the serp belt in place of the v-belt and a weight reduction in the damper's hub pulley and the w-p and alt pulleys. I actually have a machine shop that has the material and will make them for the return of a favor for some cnc programming I did for them so it is just a matter of time now. Not an immediate priorty though. It was surprising the amount of research that went into it.
 
Hello Randal,
Yes, the pulley (Revington TR) was designed for using a shortened extension (Moss 837-525). I use a blue TR6 fan - no red or yellow was available.
I feel that the parasitic power loss is minimal using this system and that adding the electric fan is needlessly complicated, in my case. I do see the advantage in hotter climates.
I see that Moss carries a dampened pulley, but it's not drilled for the fan extension.
Steve

SWC_1168_fan pulleys.jpg
 
Thanks for the info, guys.
 
I have a thin belt conversion from a local supplier here in Oz. I understood that the harmonic balancer was a modified MGB part.
 
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