Nismo87SE's link eventually leads here, which is good re-build info: Cold Idle Fix
Your Koyo is the reason you are running cold. It is a well known problem. Get a higher temp thermostat and/or take a piece of sheet metal and block off about half of the radiator so it doesn't get a lot of air flow. Then remove the sheet when you go racing.
Your Koyo is the reason you are running cold. It is a well known problem. Get a higher temp thermostat and/or take a piece of sheet metal and block off about half of the radiator so it doesn't get a lot of air flow. Then remove the sheet when you go racing.