Exactly. I'd like to know what tuner felt safe doing it. Why not run less boost and more timing? That should help with iat2 temps.
Upgrading cooling capacity on H/E
- Thread starter buexdreux
- Start date
Exactly. I'd like to know what tuner felt safe doing it. Why not run less boost and more timing? That should help with iat2 temps.
It wouldn't be fair to say the heat exchanger alone is responsible for the cooling. The whole system has to work together as a whole. Plus my intercooler is modified from stock. This is how the inlet / out let looks stock.
I wanted a more direct flow in and out for maximum fluid speed. I also wanted larger capacity so I removed those and centered my inlet / outlets and used 1" ID connections. It looks like this now.
Combined with the dual 10" SPAL fans it's fair to say the heat exchanger sheds heat well. I plan to run a couple temp sensors this summer on the inlet and outlet and data log what sort of temp drop is occurring there.
I am by no means the pioneer here. Others have done the same and are running similar setups including the intercooler mod for flow, trunk mount tank and a very powerful pump.
The impressive thing is IAT 2 temps actually drop during WOT pulls. I've never seen anything like it. Meaning if your IAT2 is say 130 F and you go WOT it'll instantly drop to say 115 and then continue to drop another 4 or 5F through the pull.
Probably one of the more impressive ones I've seen is a guy in Hawaii who's car I tuned. He was running in very hot humid temps around 95F + and his IAT2 temps would be around 130 ~ 134 cruising. He's go WOT and it would instantly drop to mid teens and through the pull it would continue dropping. He'd see around 110 F IAT2 temps. He was on a 2.9 Whipple.
I've seen 3.4 Whipple cars with IAT2 of 88F in 60F ambients with similar setup. On the hit around 94F and by the end of the pull 88F.
So I read the first two threads and then gave up. It was just people's comments or uneducated remarks saying a fan will block the air. Seems no one ever tested it.
I've done plenty testing and I'm telling you with absolute certainty that coolers benefit from a fan even at highway speeds. I don't claim to know 100% why but I have a theory it has to do with how the air splits around a car at speed. Not all the air is forced directly through the opening and through the cooler. It goes up and over the hood and under the car possibly creating low pressure areas that the air doesn't force through?
Not to long ago I ran into this again, tuning an auto swapped Cobra, 4r70w, the trans cooler was put right up by the grill opening for direct air. The owner was playing with this car on the highway racing it hard at triple digit speeds and guess what? that trans was over heating. So bad we had to pull off on the side of the highway. I wired up a fan which takes up the whole entire surface of the cooler which some would say blocks 90% of the air but guess what? Now that cooler was super effective and no matter how hard we beat on it the trans temp stayed nice and cool.
I have many other examples over the years. Time and time again it has been my experience that coolers / heat exchangers are so much more effective with a fan(s) even at highway speeds.
I've always found fans improve cooling, from tiny trans coolers that are barely larger than the size of the fan motor all the way up to the radiator.
Heck I once built a forged motor, turbo'd E85 honda for the hell of it. Those cars have tiny half size radiators and running it hard on the highways in mid summer heat the car's temps would slowly creep till it was getting to over heating and this is doing 70 to 100+ mph. I adjusted the ECU to keep the fan on even at highway speeds and boom problem fixed. Proves right there that even at very fast highway speeds the fan still pulls more air through than what it's been exposed to passing through the grill / bumper openings.
My car was tuned by Dan Desio from Pro Dyno. I’m learning about engine tuning and air/fuel ratio now. What is considered the safest limit when it comes to boost pressure and 93? The max AFR on the last pull was 13.76 at 3780 rpm at approx 18.5 lbs and the max boost was 21.87 psi at 4470 rpm with the AFR at approx 12:1. As far as running on a road course I have a pulley/tune for 15lbs.
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Maximum boost I'd run on 93 is 17-18 lbs. You need to monitor AF ratio through out the rpm range. I hope the 13.76 you see at 3780 rpms drops down very quickly or you'll be doing a engine rebuild sooner than later.
You want the af ratio in the 11.3-11.8 range.
Sorry not arguing that fans on heat exchangers work. I agree 100% that they do work. My argument is will fans on our heat exchanger be more beneficial then just air movement. Aftermarket Fans on our 03-04 Cobra size heat exchanger are in the 6" range and flow just around 350cfm. That is not a lot. You go to a bigger fan, bigger heat exchanger, or higher flowing fan and this changes everything.
The 10" and 11" fans do flow over 1000cfm each and (11" SPAL is ~1300CFM). Each 3x or 4X more than what the 03-04 Aftermarket Cobra fans flow. This would for sure change whether open air or fans are worth it.
So in my original post I asked "Did someone find a fan that was not a hindrance" and the answer is yes people are going to GT500 heat exchangers and/or going to 10" or 11" fans over the 6" fans people have been using in the past which flow 3x-4x the air.
and my response would of been "aw cool I will have to look into this as the amount of boost I am running there will need to be top notch cooling."
The 10" and 11" fans do flow over 1000cfm each and (11" SPAL is ~1300CFM). Each 3x or 4X more than what the 03-04 Aftermarket Cobra fans flow. This would for sure change whether open air or fans are worth it.
So in my original post I asked "Did someone find a fan that was not a hindrance" and the answer is yes people are going to GT500 heat exchangers and/or going to 10" or 11" fans over the 6" fans people have been using in the past which flow 3x-4x the air.
and my response would of been "aw cool I will have to look into this as the amount of boost I am running there will need to be top notch cooling."
I didn't do a lot of testing with the stock heat exchanger and fans because it's so small. However other similar sized coolers such as transmission coolers benefit quite a lot from small fans so I wouldn't think it's a problem on the stock HE.
Malcolm
Both you and GodStang have valid arguments they are just from different perspectives. Adding fans can certainly help in some situations and depending on the location of the cooler it may be mandatory. To an automotive engineer needing fans in a cooling duct only means you screwed-up the cooling duct design. My Gords HE like all the other coolers on my car are fully shrouded and sealed against the opening in the bumper cover. Adding smallish 6" fans really doesn't make a lot of sense for that kind of installation plus I like to keep things simple. The ONLY fan I have on the car is the unshrouded factory fan which will keep the engine from overheating in stop & go traffic which is all that really matters. Your set-up is a different story having such a large cooler behind the grill opening and a large reservoir, fans are probably good idea. As you know, it all depends on the installations.
Both you and GodStang have valid arguments they are just from different perspectives. Adding fans can certainly help in some situations and depending on the location of the cooler it may be mandatory. To an automotive engineer needing fans in a cooling duct only means you screwed-up the cooling duct design. My Gords HE like all the other coolers on my car are fully shrouded and sealed against the opening in the bumper cover. Adding smallish 6" fans really doesn't make a lot of sense for that kind of installation plus I like to keep things simple. The ONLY fan I have on the car is the unshrouded factory fan which will keep the engine from overheating in stop & go traffic which is all that really matters. Your set-up is a different story having such a large cooler behind the grill opening and a large reservoir, fans are probably good idea. As you know, it all depends on the installations.
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