Hey ive heard of a theory with your crank pulley to where if you have a drill press you can drill holes in the pulley itself to where your taking out weight....I dont kno how big people are talking about but i geuss enough weight to where its suppose to add Throttle response. I'm a little iffy on this so im just wondering what the 3GEE community thinks......
well yeah if you remove metal you are reducing the rotating mass thus giving you a higher RPM range giving you more power
hmm makes sence to me. But would the weight tooken off reduce the strength and risk it gettin busted or something??...hey i see your from auburn...shoot i live right down the street haha
if you mess with the crank pulley, you will mess with the harmonic balancing and you will have extreme vibrations at high rpm. that's why i didn't get a lightweight aluminum pulley for my civic. they are only good for short bursts of runs like on a 1/4 mile track but bad for daily driving or road course race where you run the car for a long time and the vibrations can get very inconvenient. although you can have your stock crank pulley lightened - taking off excess metal like the parts for the a/c and power steering, leaving only the alternator part without messing with the harmonic dampeners. kingmotorsports.com is one such shop that does it for civics. i'm pretty sure they can do the same service for any car's crank pulley. hit them up and ask.
Easy solution to that get it balanced, but really what you should aim for is a single Ally pulley which you could get made if you got the money and contacts and you would have that balanced, but really you should ditch the AC and PS and just run one pulley for the Alternator.
Then after that get the flywheel lightened or an ally one and have that balanced as well with the plate.
honestly i dont see how drilling holes in a crank pulley to reduce weight will give you anything for power with the other components still riding off of it, now if you got a pully that was smaller in diameter, that could make a minor diference.
they are saying that less rotating mass=more performance, and thats true. If your really care, aluminum flywheel > lightened crank pulley by far. What you guys MUST realize is that the stock honda crank pulley is also a harmonic balancer, and if you mess up the balancer portion or eliminate it then the bottom end and bearings will eat itself to metal shavings (seen it happen) so i would highly reccomend not eliminating the harmonic balancer
429whp 362wtq A20 TURBO. A20T>*
flywheel yea i can understand, look how big it is lolOriginally Posted by AccordEpicenter
ive got an aluminum UDP on my beretta, but the stock one wasnt a harmonic balancer. Its about an inch smaller in diameter, also about half the wieght of the OEM peice. I noticed some gains, and was dyno proven for about 5hp at the wheels... and 8-10 at the crank. In your case, i would probably leave it alone, and find a lightened pulley set, or make one work for the other pulleys.
So where do you think i can get a lighter pulley set??
waste of time and money..
thank you!someone on here who said what i was about to. the difference that little bit of metal makes vs the engine damage is not worth it. that tiny bit of weight could be better saved by not supersizing that meal you ate at mc. donalds. or you could throw the stereo and all the cd.s,the interior,the carpet,the pesky heavy back seat,the glass,scrape off the paint,it depends on how much weight you want to save. don't forget the paperclip you left on the floor,it's a whole tenth of a gram. for crying out loud this is not a freaking drag car where you need to save those .001 of a second.
Last edited by lostforawhile; 04-20-2006 at 07:31 PM.
lol however 5whp might be realistic gain for a lightened crank pulley, and thats VERY worthwhile, and every pound lost on rotating parts is FAR MORE beneficial than static weight lost by stripping parts out of the car. its like if you removed 60 lbs of shit from your trunk its not that much, but if you added that 60 lbs to your wheels or your flywheel, ur car would be god damn slow.
if shaving off the PS and AC grooves on teh stock pulley is safe and doesnt mess with the harmonics, I am alllll for losing them to drop 2-3 lbs. because im sure its worth at least 2-3whp, and that is certainly worth the time.
I wouldn't do that, unless you have it proffesionally rebalanced.
You can get a pulley of a JDM or Euro 2G lude that only has a single V belt groove for alternator, yeah you'd have to change your water pump pulley and alternator pulley but can be done, these are very light and as far as i can see do not have any harmonic balancing weights on them, they also have massive drilled holes in the pulley too also great for sticking a crank wheel for ignition.
But as the others said i'd spend money on machining off the ps and ac part ahve it balanced and job done, then get a ally flywheel too and you'll be well away!!
haha maybe your not familiar with my build. everything has been proffesionally everythinged.
it would be done by the machine shop that built my motor, which i DEEEEFFFINITELY trust to do the job right.
rjudgey are those plentiful around your parts? i sure wouldnt mind a good light CP, and alt and wp pulley to go with it.... if those are parts you can find easily enough, let me know what it might set me back. im certainly interested.
Last edited by bobafett; 04-21-2006 at 07:23 AM.
Actually if you have a quality machine shop nearby they should be able to balnce the pulley out if anyone has any fears. I personally had my complete rotating assembly balanced including flywheel, crank, rods, rod pins, pistons, and crank pulley.
Just for the record heres what a good lightened aluminum crank pulley looks like on the a20.
And this ones been going strong for about 5 years and 15,000 miles.
Oh and I also have the power steering, alt (underdriven pulleys) and the water pump in aluminum
Last edited by guaynabo89; 04-21-2006 at 12:56 PM.
did you get those made just for you, or did you luck out and buy them from some weird chance of luck
and more importantly, how did you like the power gains?
Last edited by bobafett; 04-21-2006 at 07:01 PM.
I was under the impression that the inside of the pully had to be coated with somthing to keep the belts from tearing up the aluminum, but it looks like you are just running bare aluminum there?
where did you get the pullys or did you have to take them out and get them done....i want to take off some weight but its a bitch to turn the wheel with no power stering pump when parking. some onder drive pullys would make the car faster right?Actually if you have a quality machine shop nearby they should be able to balnce the pulley out if anyone has any fears. I personally had my complete rotating assembly balanced including flywheel, crank, rods, rod pins, pistons, and crank pulley.
Just for the record heres what a good lightened aluminum crank pulley looks like on the a20.
And this ones been going strong for about 5 years and 15,000 miles.
Oh and I also have the power steering, alt (underdriven pulleys) and the water pump in aluminum
1989 Honda Accord LX-i
B18c1 swap since 7/2011
175whp and 132tq
Redzone tuned
I wrote earlier that this is a waste. I think as far as mass reduction, it is. However, I think that as far as underdriving the p/s and a/c, it isn't. Underdriving your alternator makes no difference, if you understand how electric motors/alternators work, you know why. You shouldn't really underdrive the h20 pump in my opinion for normal driving, but for high rpm, that is a good idea.
The reason why I say it isn't worthwhile as far as mass reduction goes is that the small amount of mass you could remove is too close to the rotational axis to make a difference. Effort would be much better spent on a lighter flywheel. For those of you contemplating an undampened aluminum pulley, there is a long, picture filled thread on h-t about the undampened ctr pullies causing engine destruction by shattering the oil pump (b series oil pump is directly driven by the crankshaft, so the harmonics go right into it, unlike the a20) While I don't see anything like that happening on a low rpm n/a a20, I would say that it is generally accepted that a pulley lacking any dampening will reduce the bottom end bearing life. I think a lighter flywheel and a fluidampr would be the way to go.
mine is running on bare aluminum as well, and has been since the end of October.
underdrives are ok to a point. you need to realize however that the total gain is like 6-15 hp. on my thunderbird by going with aftermakret rods, pistons and such i saved 520g a set. thats 520gx6 so as a recpicating mass thats a total of like 3 lbs. Huge. As far rotational masses thats your low end torque and where its generated. Does everyone remember newtons law os mass in motion? Anyway without the pysics lessons you NEED the rotational masses. cut as far down on the recipricating masses you can and still be strong. Im going to run stock flywheel, yes it wont rev as fast but Ill kepep my torque up which is what the a20a are biult for.
Knife edge the crank, lighter pistons, rods, stuff like that. youd be amazed how effective it was on my bird. I lost.2 compression and was alittle owrried about it but when you hit the gas it goes
Re: Crank Pulley Theory???
i understand mass = lowend torq,,+ mass also means forever to spin up ur rpms. i wanna lighten a stock flywheel and was thinking bout the crankpully also i dont run a/c or p/s so i wouldnt think you would need that part of the pully. some have brought up the concept of harmonic balencer or dampener. i work on cars all day im a mechanic,, i see many harmonic balencers from the inside out this is what i see.usually theres the part that connects to the crank made of some sort of metal, then a rubber,urathane or fluid dampner, and an outer ring made of metal that the v-ribs of your belt ride on.. (on most cars that require dampning) but im sure u guys have looked at our crank pullys,,, its just that a crank pully solid metal. it does not look like there is anything to do any dampning on our crank pully.(it is most likely balenced thou) my question is if u have a machine shop cut the ps and ac parts of our crank pully off ,lighten the rest ,and have them rebalence it would that work, or would someone be rebuilding there bottem end in a few months. if it wouldnt work please explain in detail as to why it would not. ps has anyone tried this and fu**ed there bottem end or tried it and is still running the setup.
http://www.cardomain.com/ride/2158264
" you know what i really want in a girl,,, me! " bloodhound gang
I'd say don't bother with it unless you are also lightening the flywheel and at that point take it all to a shop, have them lighten the flywheel, shave the unnessary stuff off the pully and have the whole thing balanced as one.
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