testing: aluminum crank pulleys???

[Nunook]

ok, I told my boss that im purchasing some aluminum pulleys off of ebay minus the crank pulley. And he asked if i want one made?

So after talking a while he said if I can get about 10 people that want to buy aluminum crank pulley(undampened) then he will do it for about $100 each.

These will be solid billet aluminum, and either stock size

OR If someone has a suggestion on overdrive or underdrive Im listening.

I was thinking of (slightly) overdriving the waterpump/alt and underdrive ps and a/c

[mbmbmb23]

ok, I told my boss that im purchasing some aluminum pulleys off of ebay minus the crank pulley. And he asked if i want one made?

So after talking a while he said if I can get about 10 people that want to buy aluminum crank pulley(undampened) then he will do it for about $100 each.

These will be solid billet aluminum, and either stock size

OR If someone has a suggestion on overdrive or underdrive Im listening.

I was thinking of (slightly) overdriving the waterpump/alt and underdrive ps and a/c

Overdrive would be cool if we could line up belts to use.

-m

[driftin8ez]

Overdrivng the waterpump wouldn't be a good idea for someone drifting or constantly at high rpms. You will get cavitation in the water pump having a negative effect on flow. For high rpm enigne application it would be advisable to underdrive waterpump to put less wear on it. However if you still have these in a month or so i would def. consider one. Stock size for me.

[Nunook]

Overdrivng the waterpump wouldn't be a good idea for someone drifting or constantly at high rpms. You will get cavitation in the water pump having a negative effect on flow. For high rpm enigne application it would be advisable to underdrive waterpump to put less wear on it. However if you still have these in a month or so i would def. consider one. Stock size for me.

Thats a good point. And since i drift myself, I'll leave the waterpump section stock size and underdrive the a/c and ps. Sound Good???

I would need about 10ppl inorder for my boss to do this. Sort of like a group buy.

[float_6969]

Are these going to have the appropriate timing marks? Can we make sure the back of the crank pully is pretty flat? With the SDS I'll have to get new magnets and drill new holes for them and I'd want the pully to be pretty flat on the backside.

If he's making it with timing marks, flat on the back of the pully, and underdriving, I'd be down for one.

[Nunook]

ok so that makes 2 ppl, any body else?

[teddy]

So this is $100 for just the crank pulley, or 100 for all the pulleys?

Also, what would be the effect of undampened pulleys on our engine? And could we expect a decent gain out of this, or will it be a very minimal gain?

[Nunook]

if I see enough interest in the crank pulley, then Ill do a before and after dyno.

some ppl say the downside of having a solid(undampened) pulley is that the rod bearings wear out little faster due to extra vibrations. I dont know to what degree this may or may not happen. But i know alot of ppl buy unorthodox pulleys and those are undampened.

[Kouks]

If the quality is good, Im definitely down, Id like to see one made first however.

[tyrannix]

with the timing marks and everythings all good? (and able to hold magnets like Ryan asked) then im down for one

CJ

[NeedCAforS13]

some ppl say the downside of having a solid(undampened) pulley is that the rod bearings wear out little faster due to extra vibrations.

I'm not interested in the pullies, but I'm a cheap basturd. ca18's (and alot of nissan's) crank pullies aren't harmonic dampeners. the rubber isolator on the crank pulley is there to reduce shock on the belts when the a/c compressor turns on and off, not to dampen the rotating assembly. so replacing it with a solid pulley will have no effect on bearing life, but possibly could have a slight effect on a/c comressor life. I think the main purpose however is to reduce the feeling of the compressor turning on and off to the driver, not to actually protect any parts.

[Kouks]

Thank you, same goes for ka24's, since I dont even run A/C, I definitely would be interested in a w/p, and crank pulley stock sized.

[1fast200]

ok, I told my boss that im purchasing some aluminum pulleys off of ebay minus the crank pulley. And he asked if i want one made?

So after talking a while he said if I can get about 10 people that want to buy aluminum crank pulley(undampened) then he will do it for about $100 each.

These will be solid billet aluminum, and either stock size

OR If someone has a suggestion on overdrive or underdrive Im listening.

I was thinking of (slightly) overdriving the waterpump/alt and underdrive ps and a/c

I'm in for a factory size billet alum. crank pulley, but make sure if you don't need to rebalance your rotating assembly, because I don't know.

What will the approx. weight difference be?

RYSO.

[boost_boy]

To all of you who think this is your magic answer to higher/faster rpms. you're sadly mistaken. If you're interested in removing mass from your rotational assembly, focus on your flywheel's weight and not the crank's pulley. And for float_6969, you should know better. The biggest benefit of your stock pulley is the fact that it is steel and your magnets are attracted to it. With aluminum, your magnets are totally dependent upon epoxy and they will come out eventually (been there).

Why don't one of you be a guinnea pig first before everyone goes bezerko on something that hasn't been tested. The thread starter is the perfect candidate and should dyno his car before installation write a report and then dyno the car again with the pulley(s) installed and write a report and then you guys can base your decisions off his findings.

If you guys are looking for rpm/hp or faster spool-up, work on the head, turbocharger, fuel system and don't be cheap about it.

Dee

[Kouks]

Good point

To all of you who think this is your magic answer to higher/faster rpms. you're sadly mistaken. If you're interested in removing mass from your rotational assembly, focus on your flywheel's weight and not the crank's pulley. And for float_6969, you should know better. The biggest benefit of your stock pulley is the fact that it is steel and your magnets are attracted to it. With aluminum, your magnets are totally dependent upon epoxy and they will come out eventually (been there).

Why don't one of you be a guinnea pig first before everyone goes bezerko on something that hasn't been tested. The thread starter is the perfect candidate and should dyno his car before installation write a report and then dyno the car again with the pulley(s) installed and write a report and then you guys can base your decisions off his findings.

If you guys are looking for rpm/hp or faster spool-up, work on the head, turbocharger, fuel system and don't be cheap about it.

Dee

.

I am not looking for anyone of those things to happen. 100 isnt that expensive(for me) and if it takes off 4-5lbs, then Im down with it. Little weight here and there will come up to something. I dont care if it gives me any power.

I agree though it should be dynoed. Pics taken to see quality as well...

[1fast200]

To all of you who think this is your magic answer to higher/faster rpms. you're sadly mistaken. If you're interested in removing mass from your rotational assembly, focus on your flywheel's weight and not the crank's pulley. And for float_6969, you should know better. The biggest benefit of your stock pulley is the fact that it is steel and your magnets are attracted to it. With aluminum, your magnets are totally dependent upon epoxy and they will come out eventually (been there).

Why don't one of you be a guinnea pig first before everyone goes bezerko on something that hasn't been tested. The thread starter is the perfect candidate and should dyno his car before installation write a report and then dyno the car again with the pulley(s) installed and write a report and then you guys can base your decisions off his findings.

If you guys are looking for rpm/hp or faster spool-up, work on the head, turbocharger, fuel system and don't be cheap about it.

Dee

Ok, I must agree with boost_boy.

But in my case, we have a CA18DET swapped in a 1983 Toyota Starlet, no A/C, no pwr steering.Can I let a machine shop take of the extra grooves of the fan belts of the accessories that we dont use? (in a lathe).

Will it affect balance of the rotating assembly?

RYSO.