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Discussion Starter · #1 ·
I noticed why the engine was pulled out of the TSX that i bought finllay. Turns out that it had front end damage and the frame must have been pushed up against the Crank pulley, damaging the outer most lip of the Pulley. Im not going to reuse this crank pulley, so what would my options be.

K24a2
Keeping AC
Keeping PS
(if it matters on either of those)
Running a K20a2 oil pump.

What crank pulley can i use and how would it affect using the stock crank pulley?
kris
 

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Discussion Starter · #3 ·
H2nr said:
get one for an Accord K24. Its the same and it should be the cheapest.
Coolness. Is there a crank pulley that might be lighter that is factory. Im not big on the aftermarket units that are not SFI approved
kris
 

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isn't the k20a2 crank pulley slightly underdrive?
 

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There are 3 different Harmonic Vibration Dampeners for these engines. That which you're calling a crank pulley is much more than just a pulley, in fact that's very much it's secondary function. As the name implies the primary function is to dampen out destructive harmonic vibrations that happen in all crankshafts at certain rpm.
The K20A Type R unit is the smallest in diameter at 5.115", same diameter as the S2000 engines
The K20A2 is in the middle at 5.465"
The K24's use the largest diameter unit at 5.980"
The overall weight of each of them is just about the same, but the important part is the mass of the inertia ring, that part of the dampener that has the pulley grooves machined into it. It's separated from the hub section by a vulcanized rubber ring which is how the whole thing works, the vibrations in the crank are dampened out by the inertia ring through the rubber.
There are other designs as well, but this one is the most cost effective for production engines so it's the design used by all OEM's except Chevrolet, and then only on the new Z06 Corvette. It uses the Fluidamper design. Much better but also a LOT more expensive.
As the relative diameter of the crank pulley gets smaller it reduces the speed of all the pulleys driven by it, resulting in lower parasitic HP loss. The smaller diameter also allows the engine to rev quicker because the moment of inertia is lower, much the same as a light-weight flywheel.
I use the Type R unit on every engine I build.
 

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The crankshaft snout is the same on all of the K-series engines, so yes it's a direct bolt-on. You'll need a shorter belt however.
 

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Joe McCarthy said:
There are 3 different Harmonic Vibration Dampeners for these engines. That which you're calling a crank pulley is much more than just a pulley, in fact that's very much it's secondary function. As the name implies the primary function is to dampen out destructive harmonic vibrations that happen in all crankshafts at certain rpm.
The K20A Type R unit is the smallest in diameter at 5.115", same diameter as the S2000 engines
The K20A2 is in the middle at 5.465"
The K24's use the largest diameter unit at 5.980"
The overall weight of each of them is just about the same, but the important part is the mass of the inertia ring, that part of the dampener that has the pulley grooves machined into it. It's separated from the hub section by a vulcanized rubber ring which is how the whole thing works, the vibrations in the crank are dampened out by the inertia ring through the rubber.
There are other designs as well, but this one is the most cost effective for production engines so it's the design used by all OEM's except Chevrolet, and then only on the new Z06 Corvette. It uses the Fluidamper design. Much better but also a LOT more expensive.
As the relative diameter of the crank pulley gets smaller it reduces the speed of all the pulleys driven by it, resulting in lower parasitic HP loss. The smaller diameter also allows the engine to rev quicker because the moment of inertia is lower, much the same as a light-weight flywheel.
I use the Type R unit on every engine I build.
there are actually two different crank pullies for the K24 engines.

there was some info on it in a thread i made a while ago about crank pulleys. i cant remember if it was chad or hotwheelz that was talking about it with me, and im too lazy to look up the thread. but yea, do a quick search and there is some info about how the crank pullies on k24s are not all the same size.
 

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Joe McCarthy said:
As the relative diameter of the crank pulley gets smaller it reduces the speed of all the pulleys driven by it, resulting in lower parasitic HP loss. The smaller diameter also allows the engine to rev quicker because the moment of inertia is lower, much the same as a light-weight flywheel.
I use the Type R unit on every engine I build.
would slowing down all of the other pulley's PS, AC, and most importantly alternator pulley have any effect on any of there functions? Would slowing down the alt pulley result in a loss of any type of charging power or anything?

any possible negative effects?
 

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I doubt there would be major side effects if it is being used by the same engine in another car. The only issue I could see is slightly more warm AC (never use it anyway), charging issues if you had a huge stereo and idled ALOT, and slightly harder steering. Worst case, you bump your idle 100 rpm and problem solved.

IMO, the smaller pulley will fee up power and extend the life of the accessories because they are spinning less.
 

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well i dont see how it would affect the charging system since they are on the same type of motor. Now if u got a huge system or crazy light setup u might wanna get a higher output alternator
 

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outersquare said:
Is this the same as the K20A Type R / 5.115" diameter unit mentioned above?
Yes, it is. I took some pics of the crank pulleys today. The smaller (new) one is the PRC pulley (see the part # in the box) from a JDM EP3 Civic Type-R. The larger (used) one is the K20A2 pulley taken from a european EP3 Civic Type-R.



 

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btw, is there any reason why the K24 ones are so big?
 

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good info... subscribed
 
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