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-   -   Lightweight Crank Pulley? (http://legacygt.com/forums/showthread.php?t=202625)

TC207 02-28-2013 09:41 PM

Lightweight Crank Pulley?
 
Just trying to get some advice... I have a '98 LGT 2.5 5 speed with a few engine mods. It's got 8mm plug wires, ported/polished intake manifold and heads, Borla headers, 2.25 stainless exhaust w/a Flowmaster Super 10 and a stage 2 clutch. I'm thinking about putting a lightweight crank pulley, NOT an underdrive pulley on, but I've read that most don't have a harmonic balancer and could cause premature wear and potentiall failure of my crank bearings but IDK because I've never had one on any of my cars... My other question is is it even worth the $130 for the pulley because idk what kind of power gains I would get.

spooln30 02-28-2013 10:41 PM

From what I understand our engines can run a lightweight pulley due to the engine design and they only run a dampened pulley to help stop vibrations in the cabin. Now my Toyota 2jz would get destroyed running such a pulley.

pleaidestar 02-28-2013 11:14 PM

The boxer motor is balanced very very well, it is perfectly good to run a lightweight crank pulleywith side effects or codes.

You will get lower rpm responsiveness and acceleration will be a little better, I have a kartboy lightweight pulley and have had zero problems in the five months its been on my 2.2.

I'm sure since you discredited the underdrive pulley you understand the problem that piece contains?

How do those 8mm wires work out for you?

welcome by the way...

monkeyposeur 02-28-2013 11:23 PM

From what I have gathered our stock pulleys are not a true harmonic balancer. The rubber bit between the two halves of the pulley are there to join the two bits and because of different varying manufacturing conditions.

DOHCEJ22E1 03-01-2013 09:22 AM

Quote:

Originally Posted by TC207 (Post 4317861)
Just trying to get some advice... I have a '98 LGT 2.5 5 speed with a few engine mods. It's got 8mm plug wires, ported/polished intake manifold and heads, Borla headers, 2.25 stainless exhaust w/a Flowmaster Super 10 and a stage 2 clutch. I'm thinking about putting a lightweight crank pulley, NOT an underdrive pulley on, but I've read that most don't have a harmonic balancer and could cause premature wear and potentiall failure of my crank bearings but IDK because I've never had one on any of my cars... My other question is is it even worth the $130 for the pulley because idk what kind of power gains I would get.

Our engines do not have harmonic balancers.
You will also not gain any power from a lightweight crank pulley but it does help relieve stress on the engine & causes it to be more willing to turn over & spin, which is not harmful for the internals.
Basically, you will be able to get on/in & off/out of the power much easier & sooner.
For what the lightweight pulley does, I spent $75 on a Kartboy Lightweight Pulley & have been very satisfied.

pleaidestar 03-01-2013 10:19 AM

+1 on that kartboy pulley, that one is cheaper and its not the lightest one available for ej.
If you go with the lightest there is a chance you could get a misfire or a crank trigger code. Probably more so if you have a lightweight flywheel...I haven't had any issue either, I have heard of people running all the different types of lightweight pullies that are out there without issue as well.I think it was a good buy.

TC207 03-01-2013 05:03 PM

Ok thank you all for the input I'm definitely gonna go with the Kartboy pulley... And those 8mm wires are very nice I got them off EBay for $40 plus shipping and they give a noticeable increase to low end acceleration.

Kiyo1990 03-01-2013 05:54 PM

Hmm, please put up your feed back on the pulley. I would love to do that, plugs, wires, and a coil pack soon

Hemingway 03-01-2013 06:25 PM

What brand and/or part # are those 8 mm spark plug wires? I was considering getting a set of NGK wires that are 7 mm ...

TC207 03-01-2013 10:52 PM

They are B&B 8mm spark plug wires

http://www.ebay.com/itm/330523403574...84.m1497.l2649

K2e2vin 03-02-2013 02:47 AM

Quote:

Originally Posted by pleaidestar (Post 4317940)
The boxer motor is balanced very very well, it is perfectly good to run a lightweight crank pulleywith side effects or codes.

Just thought I'd chime in even though I'm a little late.

It's not actually balance that causes issues it's torsional vibration that comes from the the power stroke flexing the crank. Engines with longer strokes are more susceptible to vibration than shorter-stroke engines.

This is not an issue on Subarus because they have a relatively short stroke(even the 2.5l motors have a 79mm stroke). Though, the problem may come up with higher output cars that still run an oil pump turned directly by the crankshaft.

A great example is some of the older Honda engines(which are very reliabe, and rev pretty high). They have a 79mm-stroke B16B engine that can run without a dampened pulley just fine(you can order a lightweight one-piece "N1" pulley straight from Honda for this engine). On the other hand, it's a huge risk to run this pulley on their B18/B20 engines which have a 87.2mm or 89mm stroke; there's plenty of people who've destroyed their oil pumps with lightweight pulleys on these engines. Also, from the factory, their D15s come with a solid pulley while the D16s are dampened(84.5mm vs. 90mm stroke); even for variants with the same amount of power(D15B vs. D16Z6).

Cliffs: perfectly OK to run a lightweight pulley on our Subarus.

pleaidestar 03-02-2013 09:07 AM

Thanks for that, k2e.., what I mean by balance in the Subaru motor is the flat design pushes thrust back to the center of the motor, the reason why we don't have dampers or balancers...honda snapped to that with the k series motor, all of the pulleys on that design are lightweight. I built a few b18c's, and I have used l/w pulleys on one...it blew up on the track (but I had a good quarter time the first run) :)

Of course your absolutely correct about torsional vibration is a by product high horsepower motors. I'm saying that vibration is less prevalent in a boxer motor.

I know very little about the d series motors, when I had my civics I took the d16's out of the car tied it to my boat and used them as an anchors or counterweights.

pleaidestar 03-02-2013 09:34 AM

Quote:

Originally Posted by TC207 (Post 4319856)

28382 is the part number you have installed? What is the resistance on those wires? Reason I'm asking is because there is a thread that has been going for a minute about a plasma ignition setup that is being researched by a member...the thread is very informative. I like my ignition setup but I want a low to no resistance wire for the cold plugs that I'm using.

TC207 03-14-2013 09:52 PM

IDK the resistance to be honest because i never thought to check


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