I checked in with a friend in the Miata community who is boosted and has been chasing cooling issues for years and he confirmed the poor quality of Mishimoto rads in their application as well.

It's interesting that Koyo still makes a 52 mm core for the Miata while they only offer a 36 for the S2000 now.

 

Thanks everyone for all the feedback. I've decided to go with the Koyo.

 

I use an ebay special on supercharged car. Even in South Florida heat, I haven't had any issues.

 

Cause IIRC the Koyo isn't a cross flow. It's an up and down flow. The cross from one side to the other and back is the whole advantage in the design. the issue is loosing the upper and lower tanks eliminates the possibility of mounting points for the OEM fans. Believe me I tried. So the question is do you want a good flowing radiator that cools, or do you want stock fans. You can't really have both. I supposed you could hang the mounts up in the air above the radiator but you'd have no good structural point to mount them to. It's doesn't really work very well. Believe me I had a lot of guys ask for the stock fans. When I was first designing it I was trying to save money. The prototype Rad was a 4 digit expense. I wanted badly to save the money and run the stock fans. But without adding a lot of structure to the rad to put mounting points essentially up in the air it wasn't going to work and I nixed it as I figured it would cause more hassle then money it saved. The Fans that I went with work very well with all the factory wiring so it's worked out nicely. On my personal car I run one larger fan and that was to many amps for the stock system. I had to build a relay'd one and off for it. Some pictures of the Radiator I run in my own car. With the Cross flow and N/A I can get away with the smaller radiator (believe it or not actually cooling area size is very similar to OEM). But it gave me space for a Ram air Cold air Intake which is quite effective.

 

Which hood vents are those again please?

 

you ever going to sell that intake combo design?

 

I think a lot of people would like that cold air intake. If there was a way to work that with enough cooling capacity for a 600-800hp turbo that would be a really big deal since most of those cars seem to have the air intake behind the radiator, oil cooler, AC condenser, and intercooler.

One big advantage of yours over the CSF unit for Rockstar are the vents on the back. On a racetrack, the fan should be along for the ride. The extra vent holes on the back reduce the effectiveness of the fan which would be an issue on red flag situations and in NYC and LA traffic. Some shrouds have flaps over the openings. When the fan is providing suction it holds the flaps closed. When it isn't, they blow open.

Have you sealed your radiator so that air doesn't leak past it? I'm guessing most S2000s don't have a sealed duct without sharp edges. Those, I'm told, form vortices which close off some of the effective area.

On big difference of a top down vs cross flow and especially double or triple-pass cross flow is the increased pressure drop. One is pushing the water through lots of short tubes. The others are pushing through an increasingly smaller cross section and for a much longer distance. Sometimes that needs a more powerful water pump. Probably not an issue here.

One interesting think I came across is this a honeycomb radiator protector from Speedway. Don't know if it blocks air significantly (they say not) or how well it protects, But it is interesting.

 

Post a link where you're buying it from.

 

You choose poorly, but you are welcome for the feedback.

 

https://tune2mod.com/

They offered a 5% off discount as I was a new customer.