Hey everyone, the only thing I've changed on my car recently is the addition of a UAS front bar. I have an FMIC and the bar is very tight around the front mount and isn't letting much air in. Has anyone here got a restrictive front bar with an FMIC and still managing nice temps? Keep in mind the weather was really hot on the way up. I've just driven back from Sydney to Brisbane and the only way I was able to maintain a temp of 90*c was to remove the nose panel. With the old hacked up front bar, I'd maintain high a high 80 or just on 90 on the highway. I've checked the fan clutch, it doesn't spin freely, it spins a bit and then slows itself down, when cranking the engine it will push cardboard and rubber hose out of the way, etc. The problem I'm having is most definitely air flow, so what can I do to improve it without sacrificing my front bar? I have no undertray on the car at the moment, so any air that gets through the FMIC gap I suppose could escape underneath the radiator instead of going through it. Will putting the stock undertray thing back on improve it any? I'm thinking about running flexi pipe from the side mount ducts up to the radiator to direct some more air into the radiator. I also have an old dirty nose panel here that I'm considering cutting up to allow some more air into it. Have you guys got any other suggestions on helping it stay a bit cooler? I don't have a thermo fan hooked up, but there's one in the garage. The radiator is fine, I've had it out and it's been flushed. With the nose panel off the temp was nice at 90, as soon as I put it back on it soared to 97-98 and held there, but I wasn't comfortable with it, so I took the panel off and it dropped instantly. Obligatory road trip shot: Thanks in advance!!
There were a few tips about cooling in another thread about bonnet vents. The best/easiest idea was to run with a couple of washers under the bonnet hinges. But looking at your pic, maybe you should use some heavy gauge stainless mesh across the nose panel hole, until you get a vented nose panel.
Cheers mate. I think sticking the under tray back on, getting a vented nose panel and doing some other tricks to direct air to the rad will fix the problem. Fingers crossed, anyway... Don't know how I'll fit the under tray though, it wasn't put back on because it fouls on the FMIC. Zip ties should do it
Without the undertray the air will take the path of least resistance which is out the large hole below the radiator rather than through it. What you want to achieve is a high pressure zone in front of the radiator. Fitting ducting similar to the smic ducts in front of the FMIC and between the it and the radiator will help do this.
An undertray will help, Anti did this and temps dropped 5°c from memory, take a look through his threads.
Hi, temps up around 100 indicate you have a bigger problem than the front bar. That design has huge openings, you should be getting much more air through (albeit through the core of the front mount) than you were with a fatory bar. Refit the lower tray, or speak to UAS about getting one of these trays which runs from the intercooler to the radiator cross member. Just FYI I have recently switched from vented to standard nose panel and found it has improved cooling. Sounds like you need to take a long hard look at your fan and clutch.
My cooling mods: 56mm Radiator FMIC Ducting Vented stock nose panel DIY sheet metal radiator air guide and undertray Vented bonnet Bonnet spacers This setup would not go above 90 degrees during the 42 degree day we had recently, and usually sits on 78 degrees (16psi boost). Ducting air to your radiator will help but you all need to be wary of the air dam created after the radiator - you need to provide an avenue for air to escape so that your radiator can work effectively. Hope this helps!
Start with an ally undertray, then a vented nose. In the meantime, space your bonnet hinges with a couple of washers, or pull the rubber seal off the back
Thanks everyone. I'm going to put the stock undertray and the wheel arch inserts back in today and test it. I took the wheel arch inserts out when I put the new bar on and the air is obviously just escaping under the radiator and either side of it. Rob, I tested my fan clutch, it was working fine. The UAS Bar cut down a ton of airflow over my stock bar because it was hacked to the shithouse: Plus it had the wheel arch liners and air wasn't escaping out the sides. Removing the nose panel was the only way I could get air into the radiator itself. It dropped temps by 10c. I tested my fan clutch using the methods on here and prior to the bar, my car wouldn't go above 90, so it's a question of air escaping instead of going through the rad. In my mind, anyway. I can't find the stock nose panel I've got around here for the life of me. I hope I didn't chuck it out :/
the warm ash filled hot air wuoldnt have helped either. but yes, put the wheel liners back in and the undertray, it will push the air up into your radiator instead of escaping
yup, the airs going everywhere EXCEPT through the radiator. reinstall all the gaurds, and you should be seeing much btter temps.
I had a hard time installing an OEM front under tray with a FMIC, the one I made that dropped my running temps 5* was out of a sheet of plastic from bunnings. check my thread. Fan clutch is shagged. Your description of the "tests" match what mine was doing. replace it, at worst it's preventative maintenance, forget the vented nose panel and all that brouhaha front bar has nothing to do with it, check this thread for additional info http://www.aus300zx.com/forum/showthread.php?t=317354&highlight=stop+overheating
Well my car doesn't get hot whilst idling for extended periods and all of the tech articles I've read have said that a rooted clutch fan will see temps climbing whilst idling for long periods. Was yours fine until you were in motion?
Also forgot to mention, I had a similar idea to you Anti, but I'm going to cut up a plastic garbage bin because icbf going to bunnings, lol.
Well I put all of the air guides back on the car and modded them so there are scoops underneath the bar picking air up. Took the car for a thrash, it's 32 in Brisbane at the moment and couldn't get it over 90. I'm sure wih a new fan clutch it will probably come down, as the fan makes a shonky sorta noise, as if it's wobbly? So the plan now is to fit a new clutch fan and enjoy the temps
High temps on the highway are one of the major symptons of a faulty fan clutch. The flick test is a waste of time as i have heard that many people say it tests o.k only to replace the viscous hub as a last resort to find it was the major problem. You need to start with making a point of checking the following. Wheel arch liners in place. Fan shroud including lower piece. Thermostat condition although a faulty thermostat will usually show up at any speed. Under tray will help air flow. As will raising the rear of the bonnet and pulling the rear seal out or a vented bonnet. Start with a new viscous hub if you are positive the radiator is in good condition. Cheers Dave
