TDR Aluminum Crank Pulley vs ATI Damper
 

I have been doing a bit of research and cannot seem to find the answer to my question. The TDR Crank Pulley seems to be constructed in a solid aluminum design with no dampener whatsoever. They claim that, "These engines are internally balanced and this process has improved even further since the 90s. So the description of a BALANCER does not apply to the Miata motor.". If this is true then why is it that so many people spend the extra $500 to build their engines using an ATI Harmonic Balancer :confused:? Have people cracked their oil pump gear because they were using the TDR Crank Pulley?

Answer: TDR often doesn't know what they're talking about.

Run a Powercard and an aluminum crank pulley! What could possibly go wrong?

lol dis gun be guud

the oil pump gears will balance everything out when they shatter

This is why I am asking this question now; You know, before I spin a couple of bearings from a sudden loss of oil pressure. I'm definitely not siding with Track Dog Racing automatically. They appear to be a reputable vendor and for them to stand firmly by this product I have to wonder if they're correct. Thus, why I came here to see if a solid aluminum structure is equivalent to a death sentence of an engine.

TDR doesn't build race cars/engines.

That may be true, but I highly doubt that they would sell a product without first testing their product. I could be wrong though! And I'm not assuming anything. I'm just looking for people who have tried this pulley themselves and I want to hear their experience. If I don't hear anything maybe I'll test it and report back so other people can learn of my success/failure. For science!!!!

Nobody here has tried it, because we have brains. It would behoove you to trust and not test it yourself.

I've seen firsthand some work that TDR has done. I wouldn't doubt in the slightest they would sell a product they've never truly tested.

What is it exactly that you have seen from TDR that would lessen their reputability?

A 1993 Miata that they did many thousands of dollars "worth" of work on that i owned briefly before i decided they had messed it up too badly to bother resurrecting. They don't know how to wire things properly, how to tune, or how to install a PNP megasquirt without butchering a harness.

Oh, and the motor that they/their farmed out machine shop built lasted less than 1000 miles before breaking a rod. Then they spent a long thread arguing with me that setting up a target AFR map that commanded 14.5:1 under load was perfectly fine and normal.

I'm good, fam.

Think of it this way. Tdr is in how many race cars across the country? now ask the same question about ati. Just a guess but ati is probably going to have a few hundred thousand more units in the market

The product you linked to.

Damn. That was way less work than my posts.

I wouldn't run that pulley on my engine if you paid me. Modern engines not needing a balancer.. had my chuckle for the day.

For some history... search unorthodox racing. Those pulleys destroyed countless miata engines.

They are wrong. Incredibly, hilariously wrong.

Because TDR is stupid and most people are not.

Yes.

14 days ago:
https://www.miataturbo.net/engine-pe...ageable-98282/

Hey @poormxdad , TDR owes you a bottom end.

10 years ago, a common eBay mod was to replace the OEM harmonic damper with a solid aluminum unit to save weight. Oil pump failure was virtually assured within 1000 miles of installation. History repeats itself.

e: ^^Yep, it was Unorthodox. I didn't remember the brand name. Search for "unorthodox racing oil pump failure" for some great reading.

https://forum.miata.net/vb/showthread.php?t=173225

I'd run it on mine for about $2000. That's what i need to finish my new motor i think. Give or take.

I'm confused, Concealer. If you spent thousands of dollars of work on an engine and decided to run said engine despite knowing it was improperly wired and improperly tuned I have to question your credibility. Please understand that I'm not to talk shit here. It is just that if I spent thousands of dollars building an engine I would make damn sure that everything was wired and built properly to my knowledge despite the information anyone else let me on to believe. I would never blame anyone else for my shortcomings.

I think he bought it used when he was less knowledgeable, that's how I read it.

Could be true. But my point still stands, I would still do the research amongst the Miata community and come to my OWN conclusions. This forum and useful information has been here for over a decade; Definitely long enough to gather reputable information.

...What?

I didn't wire the car. I didn't tune the car. I didn't build the motor.

I have no shortcomings. I am perfect.

I acquired the car after it exploded. I came to my own conclusions after seeing the work that was done. No further research required. I'm not sure what you're trying to teach me, i don't have any questions in this thread. :)

I'm not trying to teach anybody anything. I am just here to learn from the people here who are more knowledgable than me.

My bad. I didn't mean to assume that you were the reason the car failed. It just seemed from this quote that you were the one in control on the engine.

Sometimes, bad things happen to people who aren't Ben. Not often, though.

I think Savington's proof is easily enough to show they are talking crap.
However, it may be a good idea to read the product details again in the "on the topic of vibrations, harmonics and safety" section.

Do lightweight aluminum crank pulleys lead to premature engine failure?
They don't actually answer this question. They state that it still discussed because of previous engines requiring dampers.

Modern (1980s and up) Mazda and other Japanese engines are NOT equipped with external balancers.
They immediately contradict themselves with "The crank pulley found on 1990-2005 Miata engines is typically called a harmonic damper. This damper is a thin rubber band, less than (1/8 inch) 2mm, built into the crank pulley. This rubber is supposed to absorb something called NVH, noise/vibration/harshness."

These engines are internally balanced and this process has improved even further since the 90s.
ALL engines are internally balanced but the accuracy of the balance is what has changed. Engines are balanced better with modern machinery but the accuracy is no where near perfect requiring a damper.
Almost everyone has had a wheel weight come off and generally this alters the balance only fractionally and the car become a total sod.
Imagine that but being spun at several hundred times faster.
No imagine its held together by a quite floppy forged crank.
Pop goes the weasel.

Everything in building an engine is to survive. Balancing the rotating assembly will be very helpful as the will be less vibrations but you will still not want to risk the engine without a damper.

I wouldn't trust TDR to tune a weedwhacker let alone give me advice on it.

Dammit, dammit, dammit.

Here's my situation. My Kraftwerks Rotrex bracket broke, and I purchased the TDR bracket to replace it. It does appear to be a much better unit. Unfortunately, it requires a slightly longer belt, a 458 rather than the 457. The only four-rib 458 belt I could find was from Continental (Contitech) and it seems to be just a large rubber band. I never had any problems with belt slippage before using this belt. At the track the first time with the Contitech belt, I must have tightened the belt five times and still had slippage. I've used four-rib Gates and Daycos of various lengths after changing pulley sizes and when I deleted the a/c without issue. The 458 belt is readily available in the six-rib version from Gates and Dayco, so I decided to go with the TDR pulley. I'll put the OEM damper back on and run the four-rib belt.

Sav, I'll send you beer money. I'm getting the car ready for four days at VIR and you may have just saved me another motor.

Thanks!

Can I clear something up... Whilst a crank is balanced in terms of rotational mass and the weight hanging off the crank (rods and pistons) is symmetrical and equal, the crank still deflects under the load from the force delivered down the rod due to the explosion happening above it. Just like soldiers marching on a bridge, if those force pulses align to any of the harmonic frequencies due to the lengths of metal in the crank, then they will be additive over time and deflect the crank more and more. These pulses are less of an issue on engines that are constantly changing revs (drag cars, sort of track cars)... more so on engines that sit at static rpms (Nascar).

You don't actually need a lot of dampening to reduce additive harmonic deflection. Try bouncing on a trampoline with someone else sitting on it (they must be floppy and not rigid) and you won't be able to keep jumping higher and higher as their floppy body will absorb some energy every jump. Reduce the dampening weight and you can jump a bit higher. Remove the weight entirely and in theory you should be able to bounce infinitely high as long as there is no energy loss in the system.

- The OEM harmonic balancer uses the rubber to act like a damper to stop most of the harmonics from getting too large. The outer ring of metal is like that floppy weight on the trampoline. Rubber though can have it's own frequency but this still works fairly well, especially on street cars.
- An ATI damper is supposedly tuned to specific frequencies in the engine and it will be more effective on those, but still dampen the rest with a similar mechanism to the stock rubber damper. These work great on Nascars as the can be tuned to specifically dampen a target RPM range. They are heavy though.
- A Supermiata damper is lighter than stock, uses rubber so should act like a stock damper with more or less effectiveness. Hopefully more!
- A Fluidampr damper uses a floating fluid to reduce frequencies and supposedly works on a large range of harmonics. They used to be used in F1.
- A lightweight aluminium crank pulley does none of that. It just acts like it is part of the crank.

If the crank deflects enough a few bad things can happen. The bearing surfaces miss-align and leak oil out the sides enough so that they touch, get very hot and fuse... or the crank end where the oil pump is driven deflects enough that the oil pump gears intersect and fail.... or the crank breaks itself in two.

A couple of things to note:
1. We all typically change the rotational harmonics when we hang different rods and pistons off our cranks. This only results in minor changes to the harmonic frequencies moving them up and down the rev range. Most dampers will still work with different rods and pistons but with slightly more or less effect depending on where the harmonics fall. This is the reason why tuned dampers like the ATI damper can be less effective on highly modified engines.
2. Some of us run our engines way past stock rev ranges and that adds a whole stack of new harmonic frequencies. The higher the revs, the frequency ranges of the harmonics narrow and so tend to have less impact, but the crank is more stressed at the same time.

Some crazy people (me) have played with different mods to dampers and cranks. I run an oem stock damper with the front half cut off, spin my engine to 9k and nothing has gone boom... yet. I have also cut down a crank but have yet to spin that at speed (I have a Supermiata pulley on the shelf for that crank). Others have run the SOHC cast cranks with half the counterweights missing with success. Most of those people know what works for them, run race bearings, rebuild frequently and are willing to blow up engines to get any slight gain or for science! I don't think any serious engine builder would run an aluminium lightweight crank pulley instead of a damper.

Having a website doesn't make you a reputable vendor, sweetie. Neither does shipping parts on time when they're paid for. There's an inherent responsibility with developing a new part and some aren't willing to hire actual Engineers or experts or to even learn it themselves.

Madjak gets a :likecat:
TDR gets every :hatecat: imagineable for selling utter dumpster fire trash to unsuspecting n00bs

Like me, who bought their intercooler kit that fits like shit, and when asked about it 'it's designed like that' and 'I don't know what I'm talking about'.
​​

Thats insane that they get away with selling this stuff and saying its perfectly safe.

Too Dumb to Research?

Thanks Madjak for amazing visual! And thanks for everyone who has contributed to this thread. At this point it seems very clear on the necessity of having those vibrations dampened.
Just playing devil's advocate here, Is it possible that the timing belt, accessory belt and water pump/ alternator belt apply a dampening effect to the vibrations on the crankshaft?

If they don't have dampers, then they don't damp.

Well the idea I have in my head in that timing belt has the crankshaft "fixed" from the 6 o'clock position, the accessory belt has the crankshaft "fixed" from the 8 o'clock position, and lastly the water pump belt has the crankshaft "fixed" from the 4 o'clock position. "fixed" meaning a place of contact that the crankshaft's vibrations might be able to dampen through. What do these dampers and belts have in common? Rubber.
Like I said, just playing devil's advocate and would love to hear people's opinion. By no means am I saying that this is the way it does operate, I'm just looking for thoughts on that idea.

My opinion is that it's a fact that if things don't have dampers, then they don't damp.

Empirically speaking, no. They don't damp the vibrations of the crankshaft to any meaningful degree, which is why engines with those three belts on them but no crank damper still shatter oil pump gears.

Here's a post on it the miata.net forum from 2006 (discussing events of a few years previous to that): https://forum.miata.net/vb/showthread.php?t=173225

--Ian

Just playing devil's advocate here, "Sure! Blow your engine up! Nobody knows you or gives a fuck if it costs you $2000. Have a fucking party! Woohooooo!"

Keeping it real...

First, when I saw that pulley the first time I threw up in my mouth a little. I was so disappointed in TDR. I even talked with them about it, and the tone I used was "what the f are guys doing?"

I do feel somewhat obligated to say that some TDR parts are well designed and of good quality. I used the belt tensioner, and the A/C P/S delete solutions and found them to be good.

OP, why do you seem so intent on trying to prove that your original assertion was correct in the face of evidence. You can't just use the data and Co opt it to blame everything but the common element.

If you really want more data then you should get the pulley and run it at high rpms. Let us know how it goes!

The trampoline example is a good way of visualising a simple system but the harmonics that apply to a crank shaft are very complex. More like a swimming pool with waves of harmonics all interacting and bouncing off things. If you could slow down time and see the crank at full load you'd see it wobbling around like jelly with waves of displacement from each firing sequence moving up and down the crank, bouncing off the end and returning. The crank will also be twisting back and forth along the rotational axis changing the timing of various cylinders a little each way. Actually some of that movement goes into the timing belt and affects the timing of the valves etc. Whether or not the accessory and timing belts affect damping depends on how rigid vs elastic vs energy absorbent they are. They may even make the harmonics worse if they are elastic.

There is an awesome video of the early F1 v10 engines shifting on the dyno. They used to get this amazing warble sound as they changed gears which was caused from the crank flexing rotationally.

Holy shit thats a cool job

I've seen enough developmental engines pop due to crank damper failure or improperly spec'd dampers.
It's not like you're going to rev the tits off it driving to the Miata club meetings.
Have at it son. What do we know?

I think that I have done enough research and read enough advice from you guys to decide to go with using a damper and not fragging my engine. Thanks guys!
Now, the next question I have is going with ATI or Fluidampr? I've read from both sides who each swear by their life to their respected side. Do we have anyone here who has tried both of these dampeners?

I have experience with both. I used to resell the Supermiata/BHJ damper, but when that left the market I was stuck with suggesting the ATI to customers who were having me build them engines. So, while I have never sold an ATI, I have installed a few of them.

I am not a fan of the ATI for several reasons. Their QC is poor at best. Earlier this year they had to RMA several dozen dampers due to misaligned crank gear teeth, an issue which I brought to their attention. They apparently have had this same issue in the past as well, since I've seen at least one post from an ATI owner with a misaligned crank gear from a damper made in ~2015 IIRC. They also hold poor tolerances to the ID of the crank hub, so pressing them onto the crank nose ranges from "easy" to "impossible". Because they integrate the crank gear to the damper, you also have to install the timing belt at the same time, which is annoying, especially when you are trying to ensure that the damper isn't drawing the woodruff key up its keyway and jamming the whole thing together.

The Fluidampr is the newcomer to the market, and IMO it is the superior product. They do not integrate the crank gear, which means you can install and remove the damper without disturbing the timing belt, and it doesn't have any of the press-fit or other QC issues that the ATI has.

I only sell products which I like/use, and I only sell the Fluidampr.

Bumping this. Just saw another confirmed oil pump failure on the Trackable Miatas FB group from a guy using a TDR pulley. 500 miles and the oil pump let go.

If you are using a TDR pulley, have your car towed to a mechanic and reinstall the stock damper

...and probably replace the oil pump while you're at it.

--Ian

Wow, TDR needs to get their head screwed on straight and take that trash off the market.

Hanging my head in shame....

Gary from TDR found out about my misfortune and called me yesterday. I give him credit for the customer service part. He explained his opinions on dampers and how the pulley didn't cause the issue. I asked if he would back his claims up and warranty my next motor, after a little hesitation he said yes.

I'm too old to deal with pulling motors like this, going with the fluidampr and a 4 rib setup. Good luck to me for finding the right sized belt.

His 'warranty' ain't gonna mean shit if he's not willing to admit his product is to blame.

You'll be fine on finding a belt, they offer them in tons of different lengths, just measure the belt path with string or a longer, cut belt and order the appropriate length.

Opinions are great like that, aren't they?

I think I found the problem...
 

I finally had time to pull apart the engine that died at Summit Point while running the TDR crank pulley. I assume this isn't what the oil pump is supposed to look like.
There is quite a bit of metal flakes at the bottom of the pan and on the pickup screen.

https://cimg5.ibsrv.net/gimg/www.mia...7f05a6fa5d.jpg
https://cimg7.ibsrv.net/gimg/www.mia...fe9591516b.jpg

Merry Christmas to everyone here, and have a safe and Happy New Year,

Andddd that's why BE pumps are a thing and also why folks don't trust TDR.

Congratulations on your purchase, lol. That sucks.

There's going to be metal flakes in all of the block and crank passages, too.

It is not.

As Sixshooter said, plan on a full teardown. Tiny bits of that gear are now surrounding the lifters (if this were an NA, they'd also be inside the lifters), in between the main and rod bearings / journals, floating around in the various oil passages, and so on.

And, in all seriousness, thank you for posting evidence of why removing the crankshaft damper is a bad thing.

Alrighty then... I have two motors in the garage for rebuild. This one, which was unexpected although it only has about ~80,000 miles on it, and one with about 143,000 miles but no big issues. Should I just abandon the motor with the explodificated oil pump?

Thanks,

Yeah, it's hard to say in situations like this.

Maybe the cam & lifter bores are fine. Maybe they're not.

Based on experiance, it's a toss up. How much is your time worth, and what, if any, special parts are in this motor that you'd really like to reuse?

I would 100% use a new motor simply for peace of mind. It sucks to have to rebuild a motor right after you blow one because of something stupid. Been there done that.