SR20 Pulleys

[DeXteR]

As KA enthusiasts, we all know how hard it is to find a decent pulley set for a decent price. Aside from the crank pulley, it's hard to find the rest of the ones we need.

You can go on ebay and buy a full set of OBX pulleys (crank, water pump, power steering pump, alternator) for your KA for about $185 shipped. Not a bad deal. Or you can get a set of SR20 pulleys (water pump, power steering pump, alternator) and a crank pulley separately for about $120 shipped. That's a savings of around $65 for cheap parts versus cheap parts. I'm not going to compare name brand parts because not only is it nearly impossible to find name-brand KA accessory pulleys, prices vary between shops.

Great. So what's the point of this?

I've seen a few people run the SR pulleys on their KA. I'm just looking for some guidance on the matter.

What crank pulley do you use? An SR or a KA?What belts did you need to use? Were there any modifications necessary? Did you need to modified bolt patterns, use spacers, or use different bolts?

I know Greg (AZHitman) did this on his ka-t convertible project that's featured on the homepage. Here's a link to Part 7 of the build where they used the SR pulleys. Here's a picture:

It looks to me as though he's running a stock KA crank pulley with a set of SR accessory pulleys. The article says that they just needed to measure belt lengths and head to the parts store to find belts that fit. You'd think he would have written a tech article, but he did not. He's a busy guy, we understand; but it'd be nice to share the knowledge.

So, have any of you done this? Any experiences? If I don't get some solid answers on what exactly this setup is, I'm going to just experiment myself when I get around to that point in my build. Any input is appreciated. Thanks for your time.

[WDRacing]

I have no help here, I used all stock pulleys. If the difference is just a matter of a little underdrive, would the tensioner not be able to take up the slack?

[DeXteR]

You would think so . . . But if you underdrive all the pulleys, that slack adds up quickly. However, I doubt that anything is really underdriven besides the one at the crank. It looks like Greg utilized the stock crank pulley though. This also leads me to believe that the belt type and width are the same between the two.

So this has me wondering: Why the new belt sizes? are the pulley diameters that different between the SR and the KA? Does anyone have a set of stock SR pulleys laying around that could be measured? If there's a difference between the stock pulley diameters, I'd assume a similar difference with the after-market SR pulleys. If the difference is significant, wouldn't this have a negative affect on the accessories that are being driven?

[eazye2000]

The information on what sized belts to use are on the Unorthodox Racing website..Although, it's for only if you use just the crank pulley. So I imagine if you use the stock crank pulley, and underdrive everything else, maybe the belt sizes should be close..?

Just some random babbling. Ignore me.

[DeXteR]

Just some random babbling. Ignore me.

You need to put that at the beginning of your post to warn us - not at the end after we've all ready wasted our time reading your post!

[Jah1mon]

Sorry to dig up a old thread here, but is it possible to use a aftermarket SR20 powersteering pulley on a KA pump?

[EODguy036]

i had wanted to do this, but i really don't want much under drive if any at all, just light weight pulleys and a super damper on the crank. wish i had a set of sr20 pulleys to measure and compare to the ka. but i did find a set of ka under drive's that i've never seen before. Jet Chips Performance Pulleys for ka
Modified by EODguy036 at 11:44 PM 11/25/2009