coolant temp 237
 

thought i would share a concern/experience with my 2007 rx8

I don't have any gauges to confirm what my exact temperature was, but based off a picture in a tread https://www.rx8club.com/series-i-tec...s-move-256838/

2007 GT 60k miles, koyo, samco rad lines, new coolant bottle (all installed @55k miles) under tray functioning properly. (ambient temps around 80-90 with AC, uphill climb)

Did some canyon carving over the weekend. Noticed temp gauge (see pic). Shut off AC, reduced rpms to 3k. Temp gauge moved back to normal position in about 5 mins. Made it to a safe place to pull over. 1 hour cool down, fans stayed on for about 10 mins. Drove the car for about another 200 miles that day, drove it to work today. No driving/starting issues.

237F is technically under the max limit according to Mazda (243F IIRC) but really you should not be seeing temps that high. According to my builder (Rob @Pinapple Racing), the stock coolant seals start to weaken at sustained temps of 220F or higher. I assume you installed new coolant and drained the block when you installed the new radiator, hoses. etc?

Also, when we do canyons runs here we have long sections of switchbacks where you stay in second gear at high RPM's and relatively low speeds so in that scenario you will see really high temps even with upgraded cooling.

cool thanks for the info, yeah new coolant. Do you know if the S2 48mm koyo will fit in the S1 rx8?

Yes it will fit.

one of the two top mounting bolts for the S1 fan shroud won't line up, but I don't think it's really that big of a deal. It will still be locked in by the two lower slide-in mounts and the one bolt up top.

the top mounting point where it meets the frame is different, it will not fit, at least not drop and play.

^^I have one bolted in my S1 using the S1 radiator mounts top & bottom :dunno:

compared them directly here:

https://www.rx8club.com/series-ii-af...1/#post4683238


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Out of curiosity, did you seal the new radiator with foam?

I have an S2 car, so this is not a direct comparison, but this is how my car's cooling system typically performed at the track when it was stock with an ambient temp of 91F. 237F seems really high to me--even for an S1 car.

https://www.rx8club.com/series-ii-af...3/#post4698701

https://cimg1.ibsrv.net/gimg/www.rx8...d4437f5655.png

there are other issues, foam is a band-aid approach