Best way to get rid of water cavitation? Need helpppp

[Jared12]

Im about to get a sr20det soon and it seems they're designed for faliure. The water pump cavatates over 6000 rpm, using an underdrive water pump pulley isnt enough and you have to also use an underdrive crank pulley with the water pump pulley, which messes with the harmonic balancer, causes enough vibration to back out bolts from connecting rods and throws them through blocks. Pics of that http://www.sr20forum.com/turbo/115706-d ... ation.html Electric water pump systems are a pain to hook up i hear. It just doesnt make sense, why would companys make pulleys that kill engines. It seems that i either have to deal water cavitation and have no fun or risk throwing a rod. Whats everyone elses thoughts on this dilema

[Jared12]

Anyone? now im hearing electric water pumps are only for drag setups only. Can anyone shed some light on this

[CSUPUEBLOTIM]

I think the stance overdrive pulley is a solution. Slows down the rotation.

http://www.ebay.com/itm/Stance-Engine-O ... 96&vxp=mtr

[Jared12]

Yea i might just go with it along with a koyo radiator but some people were saying to use an underdrive crank pully too cuz just the bigger water pump pully wouldnt underdrive it enough but i think there overthinking

[TheRoadShark]

The bigger pump pulley will make the pump spin slower and reduce cavitation. A smaller pump pulley would make the pump spin faster and make the cavitation worse. A smaller pump AND crank pulley would cancel out and put you where you already are. A bigger pump pulley and smaller crank pulley would slow the pump down even more than just a bigger pump pulley, but I don't know that that's a good thing.

Feel free to correct me if I'm mistaken

[CSUPUEBLOTIM]

Ya i think the underdrive crank pulley would put you back in the same situation if used with the larger wp pulley. Nice thing to is you can use the same belt still it says. Thinking about an electric setup you would almost have to wire in a variable resistor to be able to adjust the pump speed to an extent. For all you know throwing on a generic electric pump setup it will rotate as fast as the oem belt driven pump. My vote would be to give the pulley a shot and the price isn't horrible if it works.

[Jared12]

If i were to use a bigger crank pulley and a bigger water pump pulley then they would cancel each other out(if im correct) but thats when i would got to the issue of the harmonic balancer. Idk if the SR20s have harmonic balancers i think i read somewhere that they dont have one, and idk if they were talking about the sr20de or det. I just wanna know if i could get away with just the oversized water pump pulley and if anyone else had success with it.

[TheRoadShark]

Leave the crank pulley / balancer alone, and try the larger pump pulley. Out of curiosity, how do you know you're having cavitation problems in the first place?

[Jared12]

I dont. Im about to get an sr soon but im just researching ALOT cuz i wanna build it right. I hear alot of people having this issue so i figured most SRs have this problem so im trying to figure out the cheapest way of solving this unless the cheapest is the crappiest

[TheRoadShark]

Fair enough. From what I'm seeing the cavitation happens when the RPMs are kept above 6500 rpm for extended periods of time. It's not the revving past 6K that does it, it's the staying past 6K that causes it. Not something a street car has to deal with, so not really a flaw in design. Odds are you could rev up to redline for a minute or two at a time and be fine. STAYING up there for like 10-20 minutes straight is what would be bad. As long as your temps don't climb you're fine, from what Ive read. Having said that...

Most people seem to say they ran a bigger water pump pulley and it made it go away. There's also an OEM nissan N-1 water pump that fits the SR20DE that reduces cavitation, but I can't say for sure whether it fits on the DET. http://www.frsport.com/Genuine-OEM-Sent ... 4AodYBEApA

Best I got.

[compactfean]

I spin my engine to 8k daily ....

[TheRoadShark]

I spin my engine to 8k daily ....

And there you have it. The "cavitation problem" could be something like the RB "oil problem". Not as bad or as common as it seems or people make it out to be

2 other things I seem to remember reading while looking up cavitation - one is that "having cavitation" isn't what's bad so much as engine temps climbing as a result. Thats what temp gauges are for. The other being that most stock engines at stock redline can run for about 10 minutes straight before cavitation begins to occur. So unless you're sitting at redline all day long in every gear, probably won't be a problem.

Again, someone feel to correct me if I am misinformed...