Caliber308 Posted July 16, 2011 Report Share Posted July 16, 2011 I have my MBC set to 17PSI on my 16g turbo. However...at highway...I'm running between -15 and -10 vacuum. No boosting involved whatsoever. The car only overheats on the freeway, at freeway speeds. When I slow down, it cools off, actually. If your trying to tell me that I never even tried to fit the radiator and fan in my car, your wrong. With the increased thickness of the SR20 3 Row radiator, a 14'' cooling fan will not fit between the A/C compressor and the radiator. It hits. Therefore, I have to move the cooling fan more "centered" to the radiator, to clear the compressor. Once I've done this....I've taken away any space I would have had, to mount a second fan. Here's proof I had the radiator in the car, all mounted and fabb'ed in. http://a4.sphotos.ak.fbcdn.net/hphotos-ak-ash4/263933_10150292441976672_505891671_8974705_85127_n.jpg http://a6.sphotos.ak.fbcdn.net/hphotos-ak-snc6/269571_10150293354456672_505891671_8987196_163940_n.jpg They do make thinner Dual Electric fan set ups. I've seen them down to 2 3/8". Bill Link to comment Share on other sites More sharing options...
Coke Posted July 16, 2011 Author Report Share Posted July 16, 2011 They do make thinner Dual Electric fan set ups. I've seen them down to 2 3/8". Bill I doubt they flow very much, and if they do, they are likely to be very expensive. Link to comment Share on other sites More sharing options...
UlrichWolf Posted July 16, 2011 Report Share Posted July 16, 2011 (edited) Let me put some logic to this. First, let's look at my car. Rodded out stock radiator, all 3 stock (full shroud, automatic transmission style) fans wired to fly at 180, 160 thermostat. Zerex coolant, no water wetter, nothing fancy. My car runs a very consistent 180-183 degrees as measured by my SKF contact probe. This car runs this temperature regardless of ambient temperature, or whether or not the air conditioning is on (at least it did when it worked). And before you chide me for the 160 stat, just remember that Mitsubishi's ECI strategy considers the engine fully warmed at 161 degrees, AND that a turbo car does work better cooler. It may not be as good for emissions, but it does work better, especially if you are running higher than stock boost. (Who is anymore?) Oh, and I have no underpans. My car never had them, but I would like them back. Still, never caused an issue. So, we have a car with a healthy cooling system, doing as it should. Now, let's look at cooling system troubles a little deeper. Let's start with overheating while going slow. This is almost always a fan issue, be it electrics not coming on, or tired clutch fan. If the radiator is flowing water as it should, it will cool the car without fans, as long as it gets airflow from the car moving. If you don't run the air conditioning, you can watch the voltage gauge for proof of this. The fans won't kick on and make the gauge dip...at least until you boost it hard. Come to a stop or a crawl, the gauge goes down, and you hear them start churning air. Now, on the other hand, a car that runs cool in traffic, but heats up as you drive it faster...this is normally a coolant flow issue. Consider....the water is going through at a rate metered by the sediment in the radiator rather than the thermostat, and soon enough, the water cannot flow through quickly enough to rid itself of heat, and is recirculated back into the system partially cooled. However, this can also be an airflow issue, if the air is not reaching the radiator in the first place. In a Conquest, this is a likely scenario if you have several issues stack up. OK, so knowing these two tidbits, let's apply this to Coke's car. It gets trickier here, because he has done a lot. We can rule out coolant flow, because we know the new radiator is clean. At least it should be. I'm still sticking with my original diagnosis of airflow, because several factors have changed. With the SR radiator, we don't know what new gaps have opened up that are not sealed, and diverting air past the radiator. The way the hood is shaped, and the tape seal alonside the radiator are all there to force air through the radiator, as well as the underbody diverter panel. My car, and lots of yours prove that it will work without it, but when you change radiators, you may be creating new areas for the air to flow that were not there before. Something else to consider as well is that an aftermarket fan may have a different pitch, different enough to where if it is running, and the car is moving, it may actually impede air flow through the radiator by acting as a windblock. A stock Conquest fan is only 4 or 5 blades, and some of these aftermarkets are pretty finely bladed, with a big center hub. All of this will play a role in how things flow through the radiator. Stop and consider the laminar flow of air through the front of the car, and other factors, and it may very well be that his car has NO cooling system problems, per se, rather the application just needs some engineering to make it work right, just as Mitsubishi's engineers did with the stock setup. Tim Edited July 16, 2011 by UlrichWolf Link to comment Share on other sites More sharing options...
Shelby Posted July 16, 2011 Report Share Posted July 16, 2011 lots of things can cause over heating , slow or late ign timeing,, overly lean mixture,, plug'd or restrict'd eh pipeing , huge air leak an exh that whisles is a dead gve away to a plug'd cat Link to comment Share on other sites More sharing options...
Indiana Posted July 16, 2011 Report Share Posted July 16, 2011 I didn't know this issue you had was on the highway. This is an air flow issue and not about the fan or the radiator so what has changed from stock. There's enough surface area not covered by the fan but yes if the fan can't turn fast enough to let the air flow through then its a restriction. There are shrouds made that the fans are not up next to the core they are in a box and the box is sealed providing the fan is pulling more air then the air is flowing and when the air flow increases from vehicle speed then it blows out baffles that have flaps. How much area is blocked by your intercooler. The airdam, license plate holder, bumper, intercooler all those are working against you getting the air to blow in that opening and be diverted UP to reach the core. A pre88, but I still like 87 style best, airdam has no scoop lower lip. The angle of the intercooler can divert air wrong sending what doesn't pass through your intercooler into only the lower portion of your radiator core. The core being thicker would seem to be an improvement but not if it takes a greater volume of air flowing through it to work and it would seem you can't get enough volume through it on the highway. Take the header panel and grill out and drive it down the highway and see what difference it makes. I know an oil cooler stays cool you can lay your hand on it and its cool if you drive with the header panel off. Link to comment Share on other sites More sharing options...
Coke Posted July 16, 2011 Author Report Share Posted July 16, 2011 lots of things can cause over heating , slow or late ign timeing,, overly lean mixture,, plug'd or restrict'd eh pipeing , huge air leak an exh that whisles is a dead gve away to a plug'd cat Timing is dead nuts on, at 10BTDC. My Air/Fuel Wideband bounces between 14.2 and 15.2(give or take) while cruising. Exhaust is 3inch straight thru. No cats. Muffler is a straight thru style. Not plugged. Link to comment Share on other sites More sharing options...
Komeuppance Posted July 16, 2011 Report Share Posted July 16, 2011 How's your cam timing?? -Robert Link to comment Share on other sites More sharing options...
Coke Posted July 17, 2011 Author Report Share Posted July 17, 2011 How's your cam timing?? -Robert Fine. It was checked after I put the engine in the car, after the accident. Link to comment Share on other sites More sharing options...
Starfighterpilot Posted July 18, 2011 Report Share Posted July 18, 2011 Justin, have you checked the oil temperature thermostat, in the oil filter adapter body, which controls oil flow to the oil cooler yet? It may be stuck in one position. For What It's Worth. KEN Link to comment Share on other sites More sharing options...
Coke Posted July 18, 2011 Author Report Share Posted July 18, 2011 Justin, have you checked the oil temperature thermostat, in the oil filter adapter body, which controls oil flow to the oil cooler yet? It may be stuck in one position. For What It's Worth. KEN I have not. I never knew exactly how to check that, or if it was even serviceable. Link to comment Share on other sites More sharing options...
Indiana Posted July 18, 2011 Report Share Posted July 18, 2011 (edited) It just unscrews, that big brass part. http://www.b2600turbo.com/images/IM001788.JPG I still think you should drive with the header panel off and see what happens. You're trying to funnel air to pass up through an opening in the air dam and some hits the intercooler and the rest your a/c condensor then it has to pass through fins three rows deep that are designed to cause the air flow to not free flow as to cause greater heat transfer by hitting as much surface area of the fins possible. I think you have too much back pressure by the time the air flow reaches the radiator because its not all that good to begin with and it just goes some place else, like it never all comes up behind the bumper to blow into the core. You may have to put a full shroud on and a mechanical fan and leave the electric fan inside the shroud if its thin enough or use two stock type fans with the full shrouds. As mentioned automatics secondary fan has a full shroud plug its all the same larger size as the primary. That's an SR radiator, don't they sell fans with shrouds to fit that already? Edited July 18, 2011 by Indiana Link to comment Share on other sites More sharing options...
Starfighterpilot Posted July 18, 2011 Report Share Posted July 18, 2011 (edited) I have not. I never knew exactly how to check that, or if it was even serviceable. See my reply to this post where I originally brought the oil thermostat up. It's #17 on page 1. It has a link to i-x.net where PQ shows you where it is, what it looks like fully extended and retracted and the temp set point. When is the last time you cleaned out the oil cooler internals? For What It's Worth. KEN Edited July 18, 2011 by Starfighterpilot Link to comment Share on other sites More sharing options...
Indiana Posted July 18, 2011 Report Share Posted July 18, 2011 http://a7.sphotos.ak.fbcdn.net/hphotos-ak-snc6/284211_1456031298953_1778479606_712610_6235829_n.jpg Link to comment Share on other sites More sharing options...
Starfighterpilot Posted July 18, 2011 Report Share Posted July 18, 2011 Indy, Thanks for your above reply showing the heat transfer rates of the rad and the oil cooler. Interesting info - about 14.4% of the G54B T's engine heat is removed by the oil going through the oil cooler, provided the oil cooler is clean and the engine oil thermostat is working properly. Based upon how many Starquest Factory OEM engine coolant thermostats have failed over the years, I wonder how many Starquests are driving around with a FUBAR engine oil thermostat, especially those that have a dirty engine oil system? For What It's Worth. KEN Link to comment Share on other sites More sharing options...
Coke Posted July 18, 2011 Author Report Share Posted July 18, 2011 (edited) You may have to put a full shroud on and a mechanical fan and leave the electric fan inside the shroud if its thin enough or use two stock type fans with the full shrouds. As mentioned automatics secondary fan has a full shroud plug its all the same larger size as the primary. That's an SR radiator, don't they sell fans with shrouds to fit that already? I'm going to change the fluid in my clutch fan to a heavier (10,000wt silicone) oil when I get some time. I've been so busy lately I haven't had any time to do anything for myself. I've reverted back to the stock radiator with full shroud. If I had a lower air diverter panel that fit, I'd be running one. Unfortunately, when you run an intercooler on a flatty that was not intercooled from the beginning, the air diverter panel no longer fits. The non-IC airdam is designed a little bit differently, so even a TSi or even an 85.5 diverter panel will not fit. And yes they sell fans and shrouds to fit the SR20 radiator...I just don't know if they'd fit on the car. Edited July 18, 2011 by Coke Link to comment Share on other sites More sharing options...
Shelby Posted July 20, 2011 Report Share Posted July 20, 2011 once you drive a car enought you can tell if the engine is a qt low on oil just by watching the engine temps Link to comment Share on other sites More sharing options...
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