Zefy Posted April 19, 2006 Share Posted April 19, 2006 i'm posting this because a handfull of you have/going to/are doing the ej22 swap... we've just gone through the first day of CNC machining at school today... and it seems like i'll have access to the machine a fair amount... first thing that came to mind when learning to use it is lightened crank pulleys!!! since i wanna put the ej22 into my brat i think making my very own crank pulley would be awesome... (a personall touch if you will) i need to know the EXACT dimensions of this thing... if somebody could take some accurate measurements or if you're up to it draw it in autoCAD that'd be fantasic... (perhaps a quick drawing just so i know the dimesions properly) i don't have easy access to my ej22 so help would be appreciated! at the very least if i can't make a couple sets i could save the CAD file and the G-code file so it could be used in any compatable CNC machine and i'd be more then happy to share... could also do the alt pulley! (same as above... measurements and drawings) thanks everybody! sorry mods if i can't put this here... Quote Link to comment Share on other sites More sharing options...
970subaru Posted April 19, 2006 Share Posted April 19, 2006 cnc lathe? a mill isnt going to be the best thing to make a pulley. the chunk of aluminum needed for a pulley isnt going to be cheap either. I would draw a pulley up on CAD for you but I dont have access to a pulley that is off the car for the critical measurements like keyway, crank diameter, offset, etc. I do have a micrometer set and taking a cad class right now so if someone near here wants to loan me a pulley... I'm all about handbuilt parts, and if their CNC'd all the better. maybe you could make them underdrive and silly light! Quote Link to comment Share on other sites More sharing options...
Zefy Posted April 19, 2006 Author Share Posted April 19, 2006 i have access to both a mill and a lathe... thanks:) Quote Link to comment Share on other sites More sharing options...
subaru_styles Posted April 19, 2006 Share Posted April 19, 2006 there's a allready a ton of random companys that make crank pulleys for the EJ engine..and most can be had pretty cheap. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 19, 2006 Share Posted April 19, 2006 most of the lower priced versions are underdrive pulleys. i was looking a few months ago and found nothing for stock sized pulleys on the cheap. i'd price stuff out before cutting your own. if you can come up with low priced stock dimension pulleys (and not the under-drive ones that saturate the market now), i'm in. if you're interested in under-drive pulleys (smaller than stock), they are indeed a dime a dozen. Quote Link to comment Share on other sites More sharing options...
bgd73 Posted April 19, 2006 Share Posted April 19, 2006 What is purpose of lighter one? If to gain something, what is it? The stubborness of the steel one, or other oem pulley is quite strong if it seems heavy.The subaru short crank is really sending some heat through it, and no forgiveness ("snappy torque" correct wording?) I spun one off on a 90hp EA82! I'm glad it was a steel pulley that got thrashed around to be bolted right back up.I saw this interest happen on v8's it was almost embarrasing. Wouldn't want any danger there if I seem pessimistic. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 19, 2006 Share Posted April 19, 2006 i don't like the stock design. it incorporates two pieces of metal separated by a thin rubber ring. this rubber deteriorates and will fail at some point. the stock OEM pulley can separate and is a reliability concern. people have run aluminum pulleys with no issues for a long time. a properly torqued pulley will not spin off. it's a cast iron crank and bolt, torque the nuts out of them and they will not budge. What is purpose of lighter one? If to gain something, what is it? they claim small percentage HP and mileage, that's fine but i like the reliability of a one piece design more. if they made a one-piece cast iron pulley i'd favor that over the stock POS. incorporating possible failure modes for little to no gain in funcionality is stupidity to me, but i am an engineer prone to focus on minute details noone else cares about! Quote Link to comment Share on other sites More sharing options...
bgd73 Posted April 19, 2006 Share Posted April 19, 2006 The rubber ring certainly acknowledges what I was trying to say... If aluminum was a good alternative, you would think the experts at subaru with the aluminum engine block would be quite aware of it.I heard the word "resonance" and that ring buffers it. (I used to say "it************z" or other retarded analogy) I would trust OEM till it fell apart, realize a decade or more went by and silently replace it. Note, there is nothing aluminum spinning on a subaru, It is always casing for something that does. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 19, 2006 Share Posted April 19, 2006 If aluminum was a good alternative, you would think the experts at subaru with the aluminum engine block we can banter all day long but aluminum parts for this application are perfectly acceptable. cast iron is cheaper than aluminum and the use of more expensive material for that part doesn't fit in their design philosophy for whatever reason. just because subaru didn't use it doesn't mean it's not acceptable. that's horrible logic. subaru, or any other car manufacturer does not make decisions solely on reliability or performance. many cars get better gas mileage, performance and reliabilty out of non-OEM parts or designs. why...well i could speculate but that's the manufacturers call, not mine. the OEM design is good (in subaru's case, can't say that about them all....ha ha...) and not a bad thing and i wouldn't fault anyone for sticking with it. but to say everything else is inferior is not valid. Quote Link to comment Share on other sites More sharing options...
Zefy Posted April 19, 2006 Author Share Posted April 19, 2006 alright now that the debate is over... (yes it is over!:-p) i still need measurements! i'll look into cost of materials... i'd assume i need high grade aluminium for this... (we make small aircraft landing gear parts and boat props so i think that stuff should do dandily) and yes i don't want underdrive... slowing down my accessories would suck... i use WAY to much power for that! so if anybody could get me some #'s that'd be fantastic... Quote Link to comment Share on other sites More sharing options...
blitz Posted April 19, 2006 Share Posted April 19, 2006 i don't like the stock design. it incorporates two pieces of metal separated by a thin rubber ring.a.k.a. "Harmonic Damper", a fairly standardized part throughout the auto industy for the last 60 years or so. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 20, 2006 Share Posted April 20, 2006 a.k.a. "Harmonic Damper" i was explaining it for those that don't know and the possible failure mode associated with the design. crank pulley, harmonic balancer, harmonic damper are frequently used to describe each other without much thought. Quote Link to comment Share on other sites More sharing options...
blitz Posted April 20, 2006 Share Posted April 20, 2006 i was explaining it for those that don't know and the possible failure mode associated with the design. crank pulley, harmonic balancer, harmonic damper are frequently used to describe each other without much thought.It's exactly that lack of though that gives rise to mis-information. I'm all for well thought-out explanations, so allow me to finish my thoughts. 1. Harmonic dampers are not pulleys. 2. Pulleys are not harmonic dampers. 3. Sometimes the components and functions of a harmonic damper and pulley are combined together, ala Subaru. The harmonic damper is sometimes incorrectly referred to as a harmonic balancer. It performs absolutely no balancing function whatsoever. The harmonic damper is sometimes incorrectly referred to as a vibration damper. It performs absolutely no vibration damping. The harmonic damper does one thing and one thing only: It damps the peak fundamental torsional resonance of the crankshaft. The crank rings like a bell, to wit: it has a fundamental frequency and a harmonic series. If you tapped on the rod journal with a brass hammer, you would hear a distict note. When the engine's speed matches-up with the crank's fundamental frequency, phase-coherence develops and the crank begins to torsionally ring (essentially twisting and un-twisting). Not good ...it forms stress-nodes on the crank and also feeds harmonic energy back into the rods in a direction that opposses their direction of travel. It's no secret that Subaru seems to put a lot of thought into engine longevity and apparently thinks the damper should be there. Understandably, if the damper/pulley unit isn't robust enough to last the life of the rest of the engine, it should probably be replaced before it fails. IMO, it shouldn't be removed from the equation by replacing it with a pulley. **** ******! Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 20, 2006 Share Posted April 20, 2006 It's exactly that lack of though that gives rise to mis-information. i agree. you're addressing off-topic items i was trying to stay on topic for this persons interest, so i felt the lengthy definitions were not necessary. your input on the subaru design being necessary is on-topic, he may be interested in that. alright now that the debate is over... (yes it is over!:-p) i do have the EJ22 item you're looknig for that i could pull off and send you, but i would want it back soon. can you ship it back to me? Quote Link to comment Share on other sites More sharing options...
Zefy Posted April 20, 2006 Author Share Posted April 20, 2006 i do have the EJ22 item you're looknig for that i could pull off and send you, but i would want it back soon. can you ship it back to me? no thats ok... i have access to my own but its 40 minutes away and i can't go out there all the time... it would be easier for me to go get mine then for you to send it to me... thanks for the offer though! perhaps it would be easier if i just went and got it... then i'll be sure my measurements are accurate... Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 20, 2006 Share Posted April 20, 2006 perhaps it would be easier if i just went and got it... then i'll be sure my measurements are accurate... mine is on a good engine so i don't want to get rid of it. nor would i trust my abilities to measure it. i got tape measures, nothing fancy in that department. Quote Link to comment Share on other sites More sharing options...
blitz Posted April 20, 2006 Share Posted April 20, 2006 i agree. you're addressing off-topic items i was trying to stay on topic for this persons interest, so i felt the lengthy definitions were not necessary. your input on the subaru design being necessary is on-topic, he may be interested in that.My posts are for everyone Gary not just you. The choice to read or not to read remains an individual one so nix the "straw man". It ain't flying. :-\ Here's the condensed (retard) version of my completely on-topic previous post. Ready? Here goes: DON'T REMOVE THE DAMPER. (Why? Read the previous full-version of my completely on-topic post.) **** ******! Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 20, 2006 Share Posted April 20, 2006 My posts are for everyone Gary not just you. i never said they were? that's what PM's are for. Here's the condensed (retard) version of my completely on-topic previous post. Ready? Here goes: DON'T REMOVE THE DAMPER. (Why? Read the previous full-version of my completely on-topic post.) not sure why you're patronizing. you've mentioned your stance, i don't see a need to use derogatory remarks. i'm not trying to argue or say you're wrong? it wasn't completely on-topic, but that is a matter of oppinion. topic is about interest in a lightened crank pulley. if someone posted "anyone interested in some EA82 lifters?", i would not post a diatribe every time about the difference in lifters and hydraulic valve lash adjusters. frankly i wouldn't read it because i'm not interested in any EA82 lifters at this time. now for aluminum crank pulleys i'm interested in those. Quote Link to comment Share on other sites More sharing options...
Legacy777 Posted April 20, 2006 Share Posted April 20, 2006 The debate between whether using the stock pulley w/ damper or aftermarket aside......you'll spend way more money & time doing it yourself then just buying one, or for that matter a complete set. I'm going to re-open this thread so Greg can try and get the answer's he's looking for regarding the pulley dimensions, etc. Please do NOT post arguing about the damper or other issues. If you can help Greg out, please do so, otherwise don't post. Thanks Josh Quote Link to comment Share on other sites More sharing options...
blitz Posted April 21, 2006 Share Posted April 21, 2006 Alright, apologies ..kissy, kissy. :-p **** ****! Quote Link to comment Share on other sites More sharing options...
ballitch Posted April 21, 2006 Share Posted April 21, 2006 if your going to make an alternator version, make it smaller than stock, so it spins the alt. faster at lower engine speed ( aka idle) that way your volts wont go down as much at a stop sign or light with radio, headlights, brake lights, and all the other stuff sucking juice out of the battery. but as for crank pulleys, i think your wasting your time, they are so cheap already, it would suck to spend money on a part that you can get cheaper, however, if you could source a perrin crank pulley like mine that isnt underdriven you could copy it and sell it for alot cheaper than $120 like i paid for mine. ~Josh~ Quote Link to comment Share on other sites More sharing options...
Zefy Posted April 21, 2006 Author Share Posted April 21, 2006 if you could source a perrin crank pulley like mine that isnt underdriven you could copy it and sell it for alot cheaper than $120 like i paid for mine. that'd also be illegal...:-p however, i like the idea about making the alt pulley smaller... i've been looking at different pulleys on the net to see what i'd be able to do about the middle section... i need to keep it balanced but still maintain strength... (it'd really suck if the think busted in half while driving...) i'll most likely keep the stock pulley in the car with me while i'm driving so i could swap it out if it were to break... i'm not running A/C or power steering so i don't have to worry about those... (might even delete the second pulley because i won't need it) i'll see if i can get out to my engine sometime this week and begin taking measurements... Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 21, 2006 Share Posted April 21, 2006 that's also what i wanted, a one belt pulley instead of two. i have A/C, but i have electric power steering so i don't have a belt driven pump. since i'm running electric p/s i probably want to maintain alt speed as well, so that would be nice to address with the alt pulley. could you undredrive the water pump pulley to or is that likely not necessary? that's so small i'll get another cut out of steel if need be. my ideal set up would be a one piece pulley with only one belt like you're talking about. that would rock as i don't think i need two belts. Quote Link to comment Share on other sites More sharing options...
cookie Posted April 21, 2006 Share Posted April 21, 2006 Just for interest, when I used to race it was considered that a water pump took about 10 hp to drive, a power steering pump about the same. If you disconnected the field on your alternator you were supposed to be able to save 35 hp. This was on big American V8s so I imagine the Subaru stuff is smaller and more efficient. Quote Link to comment Share on other sites More sharing options...
Legacy777 Posted April 22, 2006 Share Posted April 22, 2006 Go Fast Bits have a smaller diameter alternator pulley. I am running one. Ended up buying just that pulley since I had the others. It wasn't overly expensive.....but probably more then if you made it in the states. You wouldn't be able to mess with the water pump. it's run by the timing belt, and the pulley is integrated with the pump itself. Quote Link to comment Share on other sites More sharing options...
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