So you've had 3 freinds that didn't have their engines runs as good as stock because of pulleys.
Unorthodox Racing products have been used by tens of thousands of customers since 1997. Street end users have accumulated trillions of miles with UR pulleys. Race teams have accumulated millions of hours from drag strip to road course to rally to drift. The founder has used solid crank pulleys on small displacement engines since 1993. The founders brother in law was employed as an engine durability engineer by Honda in their Ohio engine factory during the 1996-00 D Series & 1994-97 F Series development and on going testing. We know first hand from our own testing, the direct OE experience, trillions of street miles driven and millions or race hours that the stock crank pulleys are for NVH suppression only. NVH is audible engine noise heard within the occupant compartment by the occupants.
Why did they engines you talk about not run right? What were the machining tolerances of those engines before and after the rebuild? What was the balance of the engines before and after rebuild. Blue printing is not good enough. Honda engines satring in the early 90's were 0 gram balanced. Were balance shafts removed? What replacement components were used? What were the builders credentials? Was forced induction or nitrous part of the mix? What ECU was used? Who did the tuning? and on and on? $3K sounds like a very basic rebuild. A truly built engine would cost double that.
Subaru itself has said many times that there is no harmonic damper on their engines. Heck even Porsche jumped on the band wagon of solid crank pulleys with the GT3 starting with the 997.
Honda has made solid crank pulleys for almost all models directly from the factory in many global markets. The Integra & Civic Type R had a solid single belt steel crank pulley as a factory option in almost all markets but the US
There is no such thing as a harmonic balancer, it is a made up word used by people who don't know or understand the what that term means. You cannot harmonically balance an engine, the active damping necessary would be so cost prohibitive it would make the engine unbuildable.
A harmonic damper is the right term. A harmonic damper is only necessary for non-flat plane V8 engines. Almost every production V8 ever made except for a few some may know like the TVR Cerbera and most recently the late model Mustang Shelby GT350.
A harmonic damper must be interference fit (very tight press fit, even heated and pressed on) to the crank snout to function properly in its role as a damper. No engine UR makes pulleys for have an interference fit stock crank pulley. END OF STORY.
As explained earlier auto manufacturers have spent billions on reduction of NVH. Honda in their testing during the 1990's, which the founders brother in law was involved in, tested dozens of NVH crank pulleys for audible noise characteristics. Not one of those crank pulleys had any effect on the long term durability and output of the engines tested, including B & H Series engines. Look at the stock intake or exhaust. Full of baffels and resonators to eliminate NVH. Many factories bolt little rubberized weights to the chassis and engine to help suppress noise.
There are no facts to support the scare mongering, this is a lingering bad joke/urban legend that has been fueled by people who insist on trying to make power without following the rules of engine bullet proofing, using inferior quality of parts or work then wondering why they have failures. If we had a dollar for every time we've heard someone start up an engine and snap rev it off the rev limiter or cold start and drive away hard or stop after hard driving and shut down the engine we'd be rich.
Poor tuning is the other major problem as improper tuning leads to detonation which will cause damage to pistons, rings, valves, rods and bearings. So when you bolt that turbo or S/C onto your NA engine you had better be really sure you've got the right ECU and the right Tuner. For stock turboed or SC guys the canned tunes are not all they are cracked up to be, luckily for many the sensors are getting faster which is helping to minimize damage but over time it will catch up wth you.
Domestic damper makers are also trying to marketing spin and scare tactic end users into buying their dampers, which are adapted from V8 engine dampers to fit on these smaller engines. These adapted dampers are over weight, not only in effective weigh but non-effective weight, causing excessive load on the front portion of the engine. The extra weight acts like a hammer pounding away at the internals and the crank snout which wasn't designed for the additional weight. Not to mention they cost twice as much as UR solid crank pulley. Makes sense spend more money for an unnecessary damper that is heavier, leading to less power and hurt the crank snout and the internals to boot.
