hey all, still learning, so i don't post much and some patience would be appreciated, but after a fair bit of reading, i wanted to get some opinions on a new radiator. currently got a stock radiator that was bought new about 3 years about (before i got the car). i've never taken it out to the track and am unlikely to do so. i just want some piece of mind like everyone else. Some days it gets pretty hot here in adelaide and the missus likes some airconditioning!! twin pass seems to be the go and i've been looking at the GB that i missed from ZX2NV. why would i not purchase a 55mm twin pass over a 42mm twin pass? is there a disadvantage to a larger radiator? or is the best option to just get the 55mm? even just for a daily? i've had some overheating issues for a while and so did the last guy and am trying to narrow it down. i've used datascan to see where my temp has been at. i've checked the clutch fan, doesn't spin freely cleaned the aircon condenser (which was really bad) replaced lower rad hose with pipe new upper hoses had it pressure tested - no probs no oil or colouration in coolant water pump was replaced 3-4 years ago and adelaide z cars seemed to think it looked alright will check and probably replace the thermostat when i do the radiator one thought is that i just haven't maintened, checked the coolant level properlly - have been letting the air out lately as per tech article. am still to put on the lower radiator fan shroud (car didn't come with one and just picked one up) and the front splash guard (will do that after replacing radiator - and possibly getting new front bar). that should help the car is fairly stock, stock recon'd/highflow turbo, apexi airpod, james GB FMIC (which lot of people run fine), Mines ECU (which i'm wondering wether is part of the problem), new turbo back exhaust last year. I still have stock front bar - so air flow through may not be great too. Will order an Abflug type 4 bar soon to help airflow. i've got some boost leak issues (clutch booster) and some old hoses, but some of those will be removed when i take out AIV, etc and find a day when i can remove the dash to get the clutch booster out and repaired. This shouldn't affect overheating from what i've read tho. so anyway, i plan to purchase this week, so some thoughts would be great (oh and money isn't too much of an issue for the radiator - what's a coupla hundered extra for rock solid cooling???) any other suggestions welcomed!
FMIC ive found wqith the zeds i have had, that once i chuck a FMIC into the mix it blocks a lot of the air getting the the radiator and having problems... ive counteracted this previously by using i think it was called a "preditor or raptor" radiator... its a BMF of a radiator, takes a bit of effort to get it, but it is worth it... havent seen one on market for a couple years, and they not cheap, but im sure if you find one it will help, if not solve your problem
Take out the mines, and go back to a stock ecu, the mines tune is an aggressive tune! your thinking may not be far from the mark.
You probably should check the blades on the waterpump. When I got my Z the waterpump had been replaced earlier so I didn';t bother with it. I had overheating problems and got new 56mm radiator and flushed the system and still had the problem. One day I decided to pull the waterpump off and found only 2 blades out of 8 were still on the pump! Previous owner hadn't used proper coolant or somethign and they corroded away. Whacked a new one in from nissan for around $90. Never overheated since!
If your workshop tells you they checked out the waterpump then they may only have checked the pully and fan. Because pulling the waterpump off and checking it is really just one step before removing the timing belt (pain in the ass). Therefore its not normally checked out unless you're going to replace it anyway.
pretty sure the radiator test ZX2NV did a while ago showed the KOYO 53mm single pass came out on top.
decided last night to go back to a stock ecu - thanks beaver. Sounds like it will help my fuel consumption too! will change ECU, check thermostat/replace, likely to replace radiator with koyo 53mm after reading a bit. I don't really need a PWR 55mm. Will get the lower shroud and splash guard back on, pressure test and watch it from there. if i'm still having problems, then i'll replace the water pump (don't feel confident on that one yet). thanks for the input guys - appreciated. will post back with results in a few weeks
from the horses mouth a few months ago; "Gotta agree with JP the PWR twin pass is the goods when it comes to radiators and great if you have unlimited funds. I used a koyo for sometime and had great results with it but with the never ending search for more power and more nitrous a further upgrade was needed." http://www.aus300zx.com/forum/showthread.php?t=268594&page=2&highlight=koyo+53mm
One thing you haven't mentioned is the condition of your radiator cap (or the neck of the radiator onto which the cap screws)! Make sure the cap seals properly and is 90 PSI / 1.2 BAR (I think these are the right numbers). If the car has had a recent 100K km service, the water pump should have been replaced with a genuine Nissan item... DO NOT accept an after market pump as a replacement. If all is well, the Nissan system copes quite well with local conditions, FMIC or SMIC notwithstanding!
