The outer ring is captive with a snap ring so it cannot fall off if the rubber isolator fails. Some racers have had these rings come off and do damage. I think that is mostly a problem with old junky dampers. The timing marks are also nice. IMHO, racecars do no have AC or PS, and/or the racer will be happy to fabricate/adapt different pulleys. I see no reason to run a romac on a stock engine or one that will not see high RPM and it is not worth the money for most builds.

Lou

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Home of Slant6-powered fun machines

well, actually they do.

F1 cars, some of the raciest cars on the planet have power steering, so do NASCAR, so do most of the Autocross cars that I ran against this past summer.

AC, about all forms of racing have a suit and helmet cooler for the driver, just another form of AC. And back to Autocross, I like many other competitors, sat in the grid with the windows up and the AC on at the summertime Autocross events. A chance to cool off while the engine was running to warm it up for the event.


And concerning the two dissimilar metals, the damper on the front of an engine is not going to get anywhere close to the temperature where the coefficient of expansion becomes an issue. The lighter material is used to reduce weight.


Lastly the improved durability at higher rpm of a SFI certified is certainly a consideration. As large of a consideration is the need to control the secondary twisting motion of the crankshaft in an RPM range that exceeds what the factory damper was designed and tested for. The firing pulses of the pistons apply a rotational twisting motion to the crankshaft. The momentary stopping of the pistons at TDC and BDC arrest that rotation. The flywheel - torque converter balance that action on the back side of the crank. The damper does the same on the front end of the crank.
Interesting that it is said that a belt driven supercharger can act as a 'damper' stabilizing the front end of the crank. I would think that other FEAD (front end accessory drive) devices would have a similar effect, to a degree.

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Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

Yes, the gilmer belts can/do dampen harmonics due to their large mass and surface area. V-belts can also, but on a smaller scale because they dont cover as much real estate. Serpentine belts may even be a step above v-belts. But either, is slight, compared to a huge blower belt.
BHJ has also made SFI balancers/dampners for a lot of racing inlines in the past. They're not cheap if you are the first one to request one. But they likely could have already done it before for the Slant....wouldn't hurt to check with them!

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There's no such thing as too much cam....only not enough engine!

I have had timing chain rattle noises with 2 different slants which have shared only 2 parts, a cylinder head and a harmonic balancer. The chain rattle exists only with roller chain. My engine need billet timing set as it revs >6000.
I have had alternator located to the left side (LHD car "driver side) because I have EFI pump and surge tank at the original alternator location.
The alternator mount system is my own build. Machined and welded. It cracked couple of times and also the 8mm bolt went broken. More metal solved that issue.

At autumn I replaced the mini alternator with bigger one because the output wasn't enough for all accessories. At the same when I installed the big alternator the timing chain rattle was over. It came totally silent. I assume that the heavy alternator rotor is now "add on" for the damper outer ring.

That is the reason I ordered a ROMAC damper.

PS. The oil pump gear failure could also be because the cam is vibrating with the crank...

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1966 Dart. 170 cu.in. 200 rwhp.