I am contemplating investment in my 97 200sx SE-R vs finding a new car. I absolutely love the SR20DE engine, but I have read that they have cooling issue when running above 6,000RPM for extended periods. Underdrive pulleys are recommended, but are then essential for HPDE type of activity? It won't be an IT car out for hours at a time. I know the GRM crowd has experience with these motors, is the stock setup a mistake for track days?
What exactly are underdrive pulleys supposed to do for you?
Just out of curiousity, this is one Japanese engine that i really don't know much about for whatever reason.
Yes, you want to get either the unorthodox waterpump pulley or some other brand. Greg V sells pulleys at G Spec. The stock water pump cavitates at high rpm. Plan on getting a Koyo or Mishimoto replacement radiator as well. The Mishimoto is a the cheaper option. I think a couple vendors are selling them for $275 shipped. If you do these two things, you will not have to worry about overheating.
http://www.motoiq.com/MagazineArticles/tabid/59/articleType/ArticleView/articleId/919/Project-Racer--Part-6-The-Sweet-Scent-of-Coolant.aspx
a remote oil cooler will help too - theres only about 3.5qt oil capacity, so the added oil in the system plus the cooling action will help remove heat efficiently as well. Ive had luck with under hood venting too - a little work with the under-trays to add more airflow will cool the entire engine bay rather well.
ccrelan wrote: Yes, you want to get either the unorthodox waterpump pulley or some other brand. Greg V sells pulleys at G Spec. The stock water pump cavitates at high rpm. Plan on getting a Koyo or Mishimoto replacement radiator as well. The Mishimoto is a the cheaper option. I think a couple vendors are selling them for $275 shipped. If you do these two things, you will not have to worry about overheating. http://www.motoiq.com/MagazineArticles/tabid/59/articleType/ArticleView/articleId/919/Project-Racer--Part-6-The-Sweet-Scent-of-Coolant.aspx
+1. My friend regularly tracks his '91 SE-R and he has a Koyo, UD pulleys, and has some Water Wetter in the system, as well. No overheating issues with full hour long sessions.
93celicaGT2 wrote: What exactly are underdrive pulleys supposed to do for you?
Over 6,000 RPMs the water pump is supposedly useless due to 'captivation.' So the under drive pulley slows down the water pump and keeps it in a RPM range that is still effective.
The UD pulleys are $200 - 250 then more for a radiator.... I think I am going to keep looking for a new ride.
Would you like to sell me the 200sx for cheap? 
Um, how long are you at 6000rpm on the track? Any idea?
Seems like you could just keep an eye on the gauges at the end of the longer straight sections and slow down a little if the engine is getting a little warm.
I would say an oil cooler isn't a bad idea anyway, but might help stave off problems caused by the water pump failing to pump. RX7 oil coolers can be found pretty cheap $20-50 have it cleaned out and checked by your local radiator shop, add a oil filter sandwich adapter and some lines and you're done for maybe half what an underdrive pulley costs.
I'm not sure of the design of the SR20DE pump impeller, but some have simply snipped every other blade off the impeller to reduce cavitation at high RPM (at the expense of low speed cooling flow, just like an underdrive pulley)
BTW, here's a shot of the pump: (I believe it is anyway, I don't have one nor have I ever worked on one):
I'll second the ideas to improve airflow through the radiator and engine bay using paneling to help direct the air into and and out of the radiator and engine bay.
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