Why I don't use Lightweight crank pulleys on Subarus

[@stephencruse9065]

Thank you for the info. Def not gonna install a light weight crank pulley now.

[@RobertoPerez-bg1dm]

Thanks Subaru’s . Yes Your Correct . I work on cars for years . Rob in Chicago 👍

[@raiuwu]

Very informational! Please speak louder for the idiots in the back, Dom!

[@06wrxRAR]

been using one in mine for couple years now, no problems. good pick up speed, little bit lower mpg

[@willis23jm1]

Don't listen to his crap!

[@jameswerline8742]

Dude you just literally described EVERY god damn problem I'm having and guess what's on my motor.... Freaking Perrin lightweight crank pulley..... 🤦🏻 Bought the motor with it on it

[@t.regnerus301]

And this is why I had Dom tune my wrx. Guy knows his stuff. Wish you still worked at TurnInConcepts.

[@marcelocuadrado6955]

Very interesant. Sound crazy but it´s true... good video!

[@btvaalburg]

How about using a lighter flywheel?

[@ampersandmcvinegar5681]

Thanks. Since I've started watching your channel I've switched back to the OEM dampener, replaced the recirc tube on my bov, and installed your cooling mod. Next is the oil mod. Thank you for your candor.

[@EJL2004]

hmmm, and I just recieved my Grimspeed light weight pulley yesterday... heavier than other light weight pulleys but still much lighter than the stock and no rubber ring insert.

[@Carlos.Rivera]

How is holding up?

[@EJL2004]

@@Carlos.Rivera So far so good! Very pleased with the better rev matching. Wouldn't do this on a high horse power application mind you, but my mild bolt on power mods (grimspeed top mounted intercooler, Cobb Turbo back exhaust,) seems fine.

[@Carlos.Rivera]

@@EJL2004 asking for my BRZ, 190hp at wheels

[@flat_life750]

So Don pairing a ATI crank damper pulley and a lighten flywheel? Would that be a good match or just keeping my flywheel stock with the damper upgrade?

[@GetaDomTune]

Yes that's a good combo

[@bradleehill9662]

You know I have a cessna 172. I have never thought to translate my airplane knowledge over to my automotive racing hobby. Thanks for awakening me to this

[@landman424]

So whats with Subaru's letter to Grimmspeed talking about the crank pulley not being a harmonic balancer?

[@GetaDomTune]

It's not a balancer

[@landman424]

@@GetaDomTune or dampener?

[@GetaDomTune]

@@landman424 there's a big difference between the two and it is surely a damper

[@GetaDomTune]

@@landman424 and for the record, grimmspeed does some shitty things and some great things. They do shitty things even knowing they're shitty. Like their AOS, for example. It actually hurts not helps. I told them back in 2009 when they sent me a prototype to test. They argued that it was just a copy of another product and were going to do it anyway because it was easy money.

[@landman424]

@@GetaDomTune What about IAG AOS?

[@marcelocuadrado6955]

The ATI fluid damper comes balanced to zero? o it´s necessary balance all engine?

[@willis23jm1]

Thts it ..even with a oem pulley a rebuild engine thats not balance going to be a serious issue

[@esoterikk1]

Is a lightweight flywheel with the stock damper okay? It's a street lightweight flywheel so it's not too light

[@GetaDomTune]

That's fine

[@angelleiva36]

So the same thing with light weight flywheels?

[@adibz959]

That's why Toyota design thier engine to have piston and connecting rod that slightly not straight up on top of the crankshaft when the piston is actually at the top dead centre. This is to prevent bearing damage

[@bensiok]

good explanations, thank you good sir!

[@swansmeister]

I wanna install gruven parts one piece billet lightweifht pulleys on my audi tt mk1 vr6. Its a kit which contains 4 pulleys. My car is already heavely tuned (NA). Are they worth the money you think? They claim 5-7 hp gains and a much more free an faster revving engine and red and heard a lot of good things about these particular pulleys from people who have em. Would you recommend them?

[@markcontreras3141]

One odd day I hear a loud bang pop out my exhaust. A happy man until I look and my smile was lost. Engine light which was usually on began blinking, I can feel my gains sinking . Such an odd day indeed but it got me to thinking . Several weeks latter I stumble upon this KZbin video, For I have a complete lightweight pulley kit on my brz , I quickly realized what I had done , my worries have only begun . Will I change my crank pulley ? It would have to be done soon . Or can I get away with simply a tune. These are the questions that I have , please respond so that I can be glad

[@cf8960]

A pro tune would fix the timing and give her some pep but driving in the long term will beat your baring's to death:)

[@dzinchenko7811]

Honestly this is great information, Very informative. Thanks for the video Dom!

[@seandavis884]

Watching this again... would you recommend the fluid dampers then, seems like this would be best for absorbing those vibrations. Also, just to clarify, if the compression slows, wouldn't another cylinder be in ignition phase compensating for this, or are they timed far enough apart to make this still happen like your sine wave illustration?

[@willis23jm1]

Absorb vibration...bro if the engine internal are vibrating its just gonna vibrate regurdless... fix the issue ... that expensive marketed product is like buying better engine mount so as not to get vibration in cabin while the engine is still vibrating... he explained option to smooth out the frequency .. heavy flywheel as well as increase in idle rpm. .. well those are easy fix without rebuilding

[@boppernostopper8598]

@@willis23jm1 lmao you're actually being arrogant as shit, you dont need to rebuild an engine to put a fucking fluidampr on, and DOM himself says below that he runs them and likes them, hes even making his own better version!

[@willis23jm1]

@@boppernostopper8598 better arrogant than ignorant, atleast I won't be fool by this crap because lack of ability to think/reason. I at no point state that engine has to be rebuild. Best way to balance and get rid of hormonics is simple to do it from internal building of engine! Not a dam external fluid damper... we are not all dealing with America old engine that where poorly balanced and needs to be balance after engines are assembled. Just use your brain and you would realise that this 1 product to balance various engine built is just ridiculous... every engine built wil be different (hormonics) best to just carry long block and get it balance with crank pulley on it.

[@6466_Scoobaru]

I was referring to this video with your reference at 7:57 in. As far as ignition timing goes. Also being that the engine is self balancing based on ignition timing that is. The counter weight of the crankshaft shouldn't matter. Because the rotation is dependent on the tuners ignition timing.

[@willis23jm1]

1 of the few people I have seen commented that have sense .... his information is so misleading.. .. most issue with these vehicle are that they are heavily modify and then claims that the pulley was at fault.... I laugh when he try to justify a light flywheel and attributing the flywheel duty to the pulley. Dwl

[@honglin5143]

Would a protune resolve the mistakes fire on the lightweight pulley?

[@GetaDomTune]

Sometimes, not usually.

[@willis23jm1]

There's no way on earth adding these pulley can affect timing... its in no way apart of the timing system... smaller diameter pulley might lessing spinning rate of alternator however this isn't enough to affect voltage or power steering (if hydraulic)

[@grandtheftauto1233]

Can’t wait for your “just light enough pulley”

[@GetaDomTune]

Hahaha. It's got a bolt on weight system to make it heavier. That's just behind in the production a little

[@grandtheftauto1233]

@@GetaDomTune oh maybe I misunderstood. I thought you had created an entirely new crank pulley

[@grandtheftauto1233]

@@GetaDomTune I’m dense nvm you’re making a new pulley that has the ability to add weights to it right

[@alberta3157]

well thats a very interesting explanation, thank you for sharing . A little question though, if i have an unbаlanced mass spinning at 2k rpm, replacing that unbalanced mass to a much lighter weight(but same dimensions) it wouldn't increase the vibration it will decrease it , no ? I mean when im working with my dremel and attaching different discs to cut stuff; at all cases the ligher wheels vibrate much less then the hevier ones. i must say its a pretty cheap dremel so even without any attachments it does vibrate a little. but those vibrations only increase with heavier attachements

[@GetaDomTune]

You're not replacing an unbalanced mass when you change pulleys. You're reducing the weight of the balanced mass. You're increasing the ratio of unbalanced to balanced making vibrations worse

[@alberta3157]

​ @Dominic Acia as i mentioned before when using a dremel ( is a pretty cheap one ) it has a "fairly" ok balanced shaft as if i use it withouth any attachements, it does vibrate a little, but when using some attachements on it, most of the cases when adding a heavier attachmenent you can clearly feel increase in the vibration and it does get far more noticable when using a hevier mass attachements . if i understood you correcly, the blanced heavier mass is used to balance the light shaft ? ( but it doesn't work like that with a dremel example i mentioned, what i'm comparing it too ) I understand that those vibration might cause resonation and cause execive bearing fatige, escpecailly in airplane motors as they spin at much higher rpm and holding a steady rpm which can even more increase the resonations, but does it actually translated as well to engine motors? car RPM is almost never steady, it is always adjusting, even at idle

[@GetaDomTune]

@@alberta3157 I'm sorry you don't understand this at all. First off, the Dremel is a terrible analogy because I'm not talking about balance, I'm talking about torsional vibrations. Using your Dremel analogy correctly would be this way: you have an unbalanced disc and you make the Dremel lighter. You would feel more of the vibrations. The weight of the Dremel damps the vibrations. Again it's a terrible and inaccurate analogy you're using that proves you have no understanding of torsional vibrations. I tried to dumb it down as much as possible, but apparently not well enough. I suggest you look up torsional vibrations and mass damping on your own at this point because I am unable to make it any simpler.

[@alberta3157]

@@GetaDomTune Well i rewatched your video as i clearly didn't pay enough attention at the first time, at 7:00 you showing a change in the amplitude, lighter mass will cause a change in frequency ( if you a looking at the torsional foces in the shaft, as it will be quicker to redirect with a ligher mass then a heavier one, a heavier one will have bigger amplitudes due to bigger force because of the mass and frequency will be slower as well, so a longer wave length) not an amilitude change if the force is constant . and at 7:35 your explaining how a lighter mass will cause a delay/early detonation causing in an unbalacned forces redirection due to bad ignition timing, but it all depends on ignition timing , doesn't the ecu adjusts it automatically accordingly to the scenario ?

[@GetaDomTune]

@@alberta3157 when idle RPM is low, ECU adds timing to increase idle speed. So no.

[@Mikey6048]

So, if I get a protune when doing other parts that require it, can the tune compensate and make a the lite pulley viable? Or is it just a bad idea, period?

[@GetaDomTune]

It can help. But you're still losing the stability of having the weight on the front of the crank, keeping it in line.

[@Mikey6048]

@@GetaDomTune I actually just came across the Fluidampr Pulley. That seems like a more logical choice regarding the longevity of my motor. Also, I have a GetaDomTune Mod on order with RSD. Any lead times on these? I am an very anxious to get it installed for the protection of my EJ. Thank you kindly for the reply.

[@GetaDomTune]

@@Mikey6048 fluidampr is a good choice. That's what I run on mine. I have over 300 backorders right now due to issues with my suppliers. I have 400 SS Ts stuck in customs and Ideal-Tridon screwed up my clamp order months ago and hasn't fixed it.

[@Mikey6048]

@@GetaDomTune Oh wow. I hope it gets sorted out for you. Those like me appreciate the time you've spent on this mod and sharing your Subaru knowledge. Not kissing your ass, but genuinely appreciate it when someone with actual experience and knowledge is willing to share. Thanks for the heads up on the parts. I'll just drive my car relaxed until I get it done. Have a great day.

[@Afos3]

Thank you for the detailed explanation. What about a lightweight drive shaft? Would that affect the balance of the engine?

[@GetaDomTune]

No. The shaft would not be hard coupled to the crankshaft

[@salspec3381]

This is the best explanation I've heard on the LW pulley debate.

[@markthompson8397]

You're overthinking this. I've ran them on a bunch of different engines over long periods of time with zero issues, including the two JDM EJ20's ive daily driven the last four years. Maybe those gimped USDM EJ25's can't cope but they're junk anyhow. They do have a ton of known flaws.

[@GetaDomTune]

wow, that sample size is amazing and your comment has zero useful data. When you hook accelerometers and crank angle sensors on an engine and see drastic increases in vibration, it isn't "overthinking"; it's evidence. You are free to do whatever you want, I don't expect you to live life by my rules or explanations. But this video is titled "Why I don't use...." not "OMG, DON'T FREAKIN' DO THIS!". Thanks for the comment.

[@bradleehill9662]

What are your thoughts on fluid dampers and when should you consider running them

[@GetaDomTune]

I like them. I run them

[@BJPr12]

Opposed forces! Your videos are awesome, learning a lot. Subscribed

[@travisshrey6720]

You state the crankshaft speeds up and slows down based on where the piston is in its stroke. That makes sense if only one piston is attached, but with four pistons for every one that would be in slowing the crankshaft down there should be another one that is speeding it up. Doesn't this cancel out the delta in crankshaft speeds you are talking about?

[@GetaDomTune]

It helps, but it is far from sufficient. When we were building airplane propulsion systems, we did extensive testing with speed and g sensors (accelerometers). The testing was done to quantify the torsional vibration frequencies the engine was producing so we could use the correct weight flywheel and durometer bushings. Since it was an airplane, keeping everything as light as possible was a priority. However, even with a big propeller on the back of the engine, we had to use a heavy flywheel and crankshaft pulley to keep the engines vibrations from tearing the prop and gear box to shreds.

[@GetaDomTune]

Also if that were the case, lightweight flywheels wouldn't trip the misfire threshold in the ECU... Which they do quite frequently on the ej205s

[@GetaDomTune]

@@jeanpaulngpingching3435 I don't have enough experience testing lightweight components on the fa to be able to give you a conclusive answer.

[@willis23jm1]

That the whole dam purpose of the flywheel to cancel out and correct errors by inertia....get that momentum going at that dead spots.. .. but you trying to drag the pulley into the mix

[@2slofouru]

Seems like you're stating the ignition timing isn't being slowed to compensate for the decrease in speed, yet the ecu should theoretically be receiving the sensor signal slower as well and effectively adjusting the ignition signal to compensate. Or does the ecu receive the signal before the crank speed slows and still sends the ignition signal too advanced? Two reasons I mention this are I ran a bored ej257 on an apexi powerfc for years with pump gas, making 340wtq. The apexi is very primitive and yet the only problem I had was eventually with they typical cylinder liner crack...which was caused by a plug oil fouling over time from a build flaw. I ran a grimmspeed pulley which is pretty light, and it was tuned with that. Now I've a sleeved block with haltech elite and lots of goodies and am debating which pulley to use...for the same reasons most of us worry over it. There is constant back and forth online on this subject and still a lot to learn obviously. For example, when we run light flywheels we also drop the effective engine system weight. By the same token, you could also say that when the transmission is engaged with the crank pulley, it is effecting its damping as well. I do like your explanation of why to keep the pulley heavy for preventing the front end loading up the bearings.

[@GetaDomTune]

That's exactly what I'm stating and you're 100 percent incorrect about the ECU getting slower signal compensating for anything. Ignition isn't time based, it's position based.

[@jack073]

What are your thoughts on ATI crank dampener? From what I understand its just a more heavy version of the stock pully

[@GetaDomTune]

Love it.

[@metaframe2k]

02:52 After the phrase "the four-cylinder Subaru engine has no counterweights on the crankshaft", then you don't have to listen. Author GENIUS ....

[@GetaDomTune]

You ever balanced a Subaru engine or any engine for that matter?

[@turbosupra2jzdragracingtob249]

Lol...Boxer engines don't have counter balance weights is why they are lighter. They use the opposing Rod/piston.

[@GetaDomTune]

Correct. Nowhere in this did I say anything about counterweight. You should look up the difference between damping and balancing. You clearly have a knowledge deficit.

[@turbosupra2jzdragracingtob249]

Dominic Acia WOW...I wasn’t correcting you or stating you were wrong. Thanks for disclosing you are complete asshole.

[@GetaDomTune]

@@turbosupra2jzdragracingtob249 I thought everyone knew already that I was an asshole. My bad. Sorry you had to learn this way. If you weren't arguing, why the lol?

[@willis23jm1]

@@GetaDomTune you know you remind me of that one individual that at university..that i just keep wondering how did this idea got here.... but I guess they do slip by now and then ... so much misleading information and to think so many took your word as gospel!

[@GetaDomTune]

@@willis23jm1 is that English?

[@michaelhite1433]

Are air~cooled VW’s cranks similar?

[@GetaDomTune]

kinda. The VW only has 3 main bearings vs the Subaru's 5. The VW Crank weighs in at 19-23lbs depending on stroke.

[@michaelhite1433]

@@GetaDomTune I was just curious if they were similar. I’ve never messed with them. I’m now having to learn about VW VR6s because my youngest son bought a Jetta.

[@jaredbawden6707]

Very useful & informative video. Thankyou

[@ryanlund1742]

This guy knows his shit an proves alot of points with Subaru's really with there was more people out here like that! Honestly I'd like this guy to set up my subaru no joke

[@dennisvanderben2719]

crap no I have no idea how to improve engine response lol, I suppose all still apply to the ef20?

[@GetaDomTune]

What's the ef?

[@Ryder-636]

Dominic Acia probably meant the FA20 but I can’t confirm since I’m not him lol

[@Ryder-636]

Dennis Vanderben try getting a tune

[@tonyregalado7281]

What's a good lightweight flywheel, Dom?

[@willis23jm1]

None ....unless its a strictly race car and high reving

[@derrickgarcia303]

Dom, so stay with stock or go heavier?

[@GetaDomTune]

I use heavier pulley with stock or a couple pounds lighter flywheel.

[@Iftrades]

I was thinking of buying one on my 370z , I have a lightweight flywheel already but scared of doing damage if I get a lighter pulley . What's ur opinion

[@GetaDomTune]

They have way more rotating mass than the Subaru. I wouldn't worry too much

[@escargod]

Thanks Dom for all your videos. Love the attitude.

[@slohachi6433]

I think a type 1 Air Cooled VW crankshaft would be, by far, the lightest 4 cylinder crankshaft in existence. Flat 4, no counterweights, less main journals, and the biggest type 1 engine was 1.6L. Edit I love your videos, btw. I was doing some research on phenolic spacers and I found your videos. Thanks for the useful info. I won't be using a phenolic spacers.

[@GetaDomTune]

No counterweights in the Subaru crank either. What does one of those weigh? Subaru crank is 18 to 20 pounds depending on model. B

[@slohachi6433]

@@GetaDomTune I have a couple stock crankshafts I'll weigh them tomorrow. I'll weigh an aftermarket crank that has the counterweights added also. On VWs there is no main bearing journal between the 1-3 and 2-4 rod journals, so high rpm engines experience crank flexing without the added counterweights.

[@GetaDomTune]

@@slohachi6433 yeah I've seen them and often thought the flexing would be significant

[@slohachi6433]

Dominic Acia Interesting results: Mexico OEM VW (cast) - 16.8 lbs German OEM VW (Forged) - 20 lbs CB Performance Aftermarket 74mm stroker with counterweights (Forged) - 20.7 lbs

[@Questchaun]

This should be why you don't use lightweight crankshaft pully on any car.

[@GetaDomTune]

Questchaun Subaru is a bit more sensitive due to their lightweight crankshafts. But yes, I agree that it isn't a good idea on other platforms

[@comonerleon]

Dominic Acia do you recommend a light weight pulley on a Mk7 Gti

[@michaelhite1433]

I believe my son and I just experienced this a few months ago on his ej22 he built with Buick L67 pistons. His plan was to run a supercharger. It never got that far. Not long after getting it running it started running rough and then had rod knock. He had an aluminum crank pulley on it. It worked out though, he swapped an ez30 into his Forester instead. After watching this, I getting a fluid dampener for my ej20 I’m building for my Forester. I have to also get one of your cooling mod kits for my motor. I’m also glad I didn’t get a lightweight flywheel now. Mine is just lighter than stock.

[@GetaDomTune]

I've never heard of someone using l76 pistons, when there are so many 22T piston options already. What were his bearing clearances?

[@michaelhite1433]

@@GetaDomTune he followed a guy on one of the Subaru pages who did it. The block had to be bored over. These pistons are from the series 2 supercharged 3.8(L67). They have anodized crowns and are cheap and easily available. Most of the 2.2 pistons were either expensive, or not in stock when he was looking. Rod and mains were perfect and the bottom end was all rebuilt. When we pulled the motor apart after this happened,the bearings had unusual wear. The knocking sounded like rod knock, only softer and the motor was stumbling. Having trouble idling. This all happened in a few minutes. We couldn’t figure out why it did this. After seeing this, it made sense. And I’ve seen several videos of people saying don’t ever use these crank pulleys, but they don’t really explain why. I never thought about how much lighter ej cranks are until this video. My VW tdi crank is noticeably heavier.

[@Sirfox_alot]

What are you thoughts on water pump pulley?

[@GetaDomTune]

What application?

[@Sirfox_alot]

@@GetaDomTune 05 wrx

[@GetaDomTune]

@@Sirfox_alot there are no options for water pump pulleys. They are not removable or changeable. Changing the size would be wrong because they are part of the cam timing system

[@Sirfox_alot]

@@GetaDomTune I beg to differ Perrin has a piece which is called the water pump pulley...just wondering what is the purpose of it? Beneficial or not what else does it does beside making a sale for the company.

[@GetaDomTune]

@@Sirfox_alot no they don't. You said 2005 WRX. That is not the same engine as a 2015 WRX. Not even close.

[@allenolivieri1773]

wat can i do to a na 2.5 ?? make that video

[@GetaDomTune]

It would just be a clip of a car crusher

[@nicholasraymond5867]

What’s wrong with the N/As? Not everyone is looking for 300+ HP, but still love Subaru’s and boxer engines. I have ‘14 Legacy limited and it’s an excellent car, just eliminating the restrictive stock intake for the Injen stage 2 made a huge difference

[@GetaDomTune]

@@nicholasraymond5867 it's an engine with screwed up geometry that's not reliable and rarely goes as many miles as almost any other engine on the market. They don't make good power for their size or weight, they burn very dirty (emissions) and they don't get good economy. So lots of things.

[@garyandreas5732]

Cool video. Have you ever had ( or could you see) a subaru motor stumbling to start and backfiring after a lightweight flywheel AND pulley, with no tune? Thanks

[@GetaDomTune]

Yes. A tune isn't going to fix the problem, it's only going to erase the check engine lights.

[@garya5257]

Actually it wasn’t a flywheel or pulley issue. It was ignition wires that were accidentally switched. The car was tuned and runs great now.

[@ronkrill2038]

full of it

[@TheCarBro]

Max volume is still not loud enough for me, I have to turn on subtitles and it doesn’t even show the right words at times

[@GetaDomTune]

Interesting. It's actually a pretty loud recording

[@whiskeyweekly7533]

Same here, it was very quiet for me.

[@bensiok]

It was perfectly fine. I think you have a problem with your internals ;)

[@roimatatamihana5681]

What if you just want it to give it the berries and don’t care about longevity

[@GetaDomTune]

Then do what you want

[@austinconey4913]

Lmao my thoughts exactly, I didn't buy a Subaru to not have fun with it

[@Sultyboy]

subscribed!

[@VenturiLife]

Or just tune your car accordingly for the crank pulley, and still enjoy the fast response.

[@GetaDomTune]

Not how that works

[@flyboynextdoor]

As a pilot and a Subaru driver I’d love to see a video on EJs in an airplane!

[@GetaDomTune]

I've left that life behind, but you can find pictures and articles I've written about it online

[@jose15238]

min 00:55 false, vw beetle and porsche ( boxer engines) have lighter cranks... And without data logs and physics/Math (free body diagrams) this video is pointless.... your graphical representation is exaggerated. Math proves theories...

[@GetaDomTune]

obviously it's exaggerated, dummy. It's a fucking white board. yes, I should have said Horizontally opposed 4 cylinders use the lightest cranks. But the boxster crank is not lighter. VW is, but it isn't even produced any longer. This whole channel is about basics. I'm not doing a free body diagram on a rotating crankshaft. GTFOH