kenny's 370z

i will try and keep this as simple as possible and what works for me may not work for you.so here it is.ever since i bought this car used at 58k it had bogging associated with heat and it kept getting worse until i decided to check the whole coolant system.everything except the radiator needed to be replaced.so i proceeded to get a thermostat replacement from orielly's which was a motorad thermo and it had a different design.(wasnt expected) and change my coolant to the blue stuff and also got a rad cap.

at the time i had my fang vents open to air and the car was still trying to get hot on me so then i proceeded to take out the thermo for testing purposes.oil temps only jumped up to 185 on the interstate however the coolant temps were staying too cold and threw a cel in 71 ambient i think it was.

still frustrated i started doing some research online about drilling holes in the thermostat.to my surprise,there is quite a bit of info on the subject.i then proceeded to cut the jiggle valve out of this motorad thermo and drill another hole exactly the same size.after doing this,i noticed the car was starting to run a little better but would still show the same bogging problems after getting on it with oil temps at 220..

so i took it back out and then cut the valve disc(what controls the coolant flow)to almost nothing as a last resort and installed it back on the engine.car was running too cold again and throwing a cel.frustrated still.so i then put the fang covers back in and took out the splash shield as to limit the flow over the radiator with my modified thermo.

reset ecu,took it for a 47 mile ride including interstate and a rural country hwy at 55 mph in 57 ambient with lots of cloud cover and cold.water dots stayed on normal on the interstate doing 80-100 and the oil was 185 where it stayed.on the rural hwy,water dot would drop to 5 but for the most part,the dot stayed on 6 and 7, on a steady cruise without stop an go.

car had good power and the oil was fluctuating between 175-180 and the best part about this is NO CEL this time.i know the coolant temp will fluctuate between 20-30 degrees,maybe higher,on this car when doing spirited runs or fast take off's.i will say that running without the fang blockers,there was too much air getting blasted on the inlet side on the side of the radiator.

i would also go and venture to say that there was so much air being blasted on the rad that it was keeping the thermo closed too much also causing heat related bog.all this before i finally figured this out was related to pedal delay,hesitation,bogging,or whatever you want to call it.of course come summer,i will have to have a bigger radiator and will try the mishimoto stat.as of now,im satisfied that the car is running excellent with no oil cooler.i will be installing a water temp gauge this weekend to start monitoring my temps instead of going blind at it.

the ecu is happy and so am i with the performance that is imo,in between too cold and too hot.im sure i will have to put some cardboard over the rad when the temps get down in the 20's.thats a no brainer and will bolt right to the two bolts holding the rad bracket.i would only do this to keep the engine at an acceptable range with no racing or driving hard.

for the most part,im sharing my info so that others can get the idea of how to keep the engine cool for spirited driving on the street and some light track duty.keeping the coolant from getting hot as hell is one of the key factors on this car with out a doubt !.take it for what its worth.and btw,i was asked to post my findings so dont hate lol.

edit; 1 more thing.car will require a 5 minute warm up period from a cold start in 50-60 degree ambient or you may or may not get a cel.