miwitte

hey guys I picked up a 07 with a ECS blower and like most here have cooling issues. I drove it home 500 miles from the DC area a month ago and got stuck for hours in traffic the temps were getting up to 240 so had to shut AC off.

So first thing I tried was to clean out the crap between condenser and radiator that every has. Also tried to mock up so side panels to direct the air better to the radiator. Neither one helped.


Next I tried flushing, purging and adding water wetter nothing.

One thing that did help was to pull off the cowl weatherstriping by the back of hood. Where my car was 210 on the hgwy at 80 and AC on its now 195-200. Drove it 300 miles up into the blue ridge 2 weeks ago worked great.

But still around town it get hot so I figured it was time to try the fan module bypass trick. I am doing this a little different as the controller will still be working as usual when you need full power hit the switch.


So basically cut the red and black wires going from the controller to the fans. I am using 2 SPDT relays one to control the black side one for the red side. the red and black fan side get wired to the common side of the relay, the red and black side from the controller connect to the NC(Normally closed) side of the relays. At this point with nothing else the fans operate as stock. now the NO(Normally open) side of the black relay goes to a good ground, the NO of the red side goes to the hot terminal stud on the side of the fuse block using a fuse inline with the wiring.

If you are looking to do this be cautious on relay selection. Most have 2 specifications in amps you will see something like 30A/20A. This means in normally closed they will hold 30 A but when energized to the NO contacts it only 20A. This is because the spring that holds them NC is stronger than the coil.

I found some killer 80A relays on Amazon for $9 then even came with the heavy duty 3/8" spade lugs. I ordered the spade sperately they are hard to find and the damn relay came with them! Just have to figure out where to mount all this tomorrow.


Ill let you know how much this helps I have a pretty good baseline as to where I am.

M M Alexander

That's almost exactly how I have mine - except is used a pair if SPDT 30 amp relays in parallel (biggest I had so I was forced to use a pair on each leg to carry the amperage) on the ground and positive. My car generally stays around 200 - 205 with the switch activated - in 100 degree HOUSTON afternoon traffic. If it's at a crawl/standstill temps get to about 220 - 226 but that's the highest I've seen with the temps outside hitting 105* and there was a traffic accident that halted traffic flow. Outside of that type of situation, I generally have the switch off. Nice to be able to over ride the computer PWM when needed. i see all the post about the high dollar fan gizmo of the month not working and I know I made the better choice of wiring in the relays to command the fan 100% at any time I choose.

5 Liter Eater

I guess I don't understand what this relay doohickey accomplishes. Why not just run a relay using something like the fuel pump for the trigger. Car on = fan(s) on full tilt.

M M Alexander

Why would you want your Fan @ "full tilt" anytime the car is running?
The SPDT Relay allows for the computer to PWM control the fan as it normally would. Tripping the installed switch energizes the relay and swings the motor winding's to the N.O. side of the relay and runs them "full tilt" until the user says other wise.
I drive my car to/from work whenever it's not rain in the forecast. Rarely (if ever) have I had a temperature related need for the fan switch to be triggered on the commute in to the office. I also use the same cooling fan switch - to over ride the temp switch of my Transmission cooler fan. At a steady cruise or even with a few throttle romps - I rarely need to engage the transmission fan.

5 Liter Eater

Because my **** runs hot! I certainly don't have a problem with it warming up.

DOUG @ ECS

If I could make a suggestion, I would recommend using a higher amperage relay then what was pictured there. Those fans draw a lot of amps, which is why the factory set up burns up so commonly.

M M Alexander

The one pictured is an 80 Amp relay on a circuit protected by a 60 amp fuse ... The relay is far from being an issue.

VetteArts

How long you have this fitting? would this have potential damage to the controller/computer?

If it does not pick up the need to run while stock, does this mean something is not right in stock standard?

miwitte

So to answer some questions yes the relays are 80 AMP, and 8 guage wire and special 3/8 spade lugs on realys. Also a word of caution on relays. Most are specified with current capacity of NC(normally closed) with spring tension holding contacts. Some have a rating of 30/20 which mean 30A NC and 20A NO. If I used that relay in my circuit it would only have 20A capacity since the bypass is NO(normally open). I looked around for a good relay got these off amazon for like 9 with the lugs and they are 80A.

2nd question about the controller and what if running it bypassed. In a previous life I was a electrical engineer and when they design components they design for failure in every part of a circuit(or they should). Not saying its 100% true but my thinking is they designed the PWM controller module to handle the fact that the fan may have went bad or circuit opened. How long you can run like that I don't know. Over winter I will probably go back to the controller

Hey just wanted to give some feedback and observations. Haven't been able to do too much driving but here is what I have noticed.
1) Before doing this I pulled off the weatherstrip from cowl and that helped highway driving temps by 10 degrees or more. I can cruise on highway 80 mph in 90 degree heat at around 198-210. Before it was probably around 220-225.
2) I added the fan relay and did the thermostat. A little pissed as the one that was in there was already 160(probably put in there when Doug did the blower in 2010) In hindsight Doug I should have asked if you possibly had records of doing that. It was a little bit of a pain under the blower and all but I did replace the "old" 160 stat with the "new" 160 stat. So it would appear that it has reduced temps when sitting in traffic. When it would go up to 230 its now 220-225. This is in 90+ heat. So one thing I noticed, that when temps are 80's and AC on temps wont go near 225. My thinking I that when it gets really hot, the condenser is dumping huge amounts of heat right in front of radiator. If I turn AC off temps are not a issue so the AC system is definitely throwing an extra 10,15,20 degrees more in front of radiator and that heat has no where to go when stopped.

I saw a pic on here somewhere where someone had added a aux fan in front of condenser by intercooler to help cool that or possible blow more air through radiator? Thoughts on that?

More than likely ill have to bite the bullet on a better radiator and fan setup since more radiator surface area will help.

Unfortunately what I really need to do to test this is sit in rush hour traffic going 5mph with AC on when its 90. If that test still pushes temps to 235-240 this was all for nothing and a bigger radiator will be needed. Its supposed to be hot tomorrow so ill see if I can get out.

There is nothing worse that having a 600HP car you just bought and cant drive your wife with the AC on. Having to open the window and turn AC off in traffic when its 95+ was not a good conversation.

5 Liter Eater

Yep, turning the AC off is the worst. LOL. A bigger radiator isn't a bad idea, especially in your situation because your cruising temps seem high as well. But the main problem is airflow when not moving. But I have dual spals and a dewitts with the fans on full blast whenever the car is running and I still can't pull enough air through the IC, condenser and radiator to keep it from overheating in traffic. It's possible dropping a grand on the D3 brushless setup would help. But I'd hate to drop that much cash and have it still be an issue. I've been debating something similar to the Pat G mod to tilt my IC more upright and get more air gap in between the IC and rad.

M M Alexander

My original set-up was with 30/40 Bosch SPDT units, I used a pair, in parallel on the ground and power. I now have just a single Temco 60/80 on each - no issues thus far and I've had this set-up for close to 2 years (though the car was not on the road for about 8 months).


I've done it - in higher temps/humidity level. August in Houston afternoon traffic at a dead stop or crawling, waiting for an accident to clear - hit 226 max - after sitting still for 15 minutes - crawling at 10mph it leveled off at 220 - rolling along at 45 got it back to 212.
That was on a 105* day @ 5:30 in the evening. Stock radiator, stock fan, ERL 416 with Paxton 1500.

I literally shot a video on the drive home yesterday evening (I originally intended it for another thread - but it got deleted after an ego driven crap fest started) ...


A/C on ice - 95* outside in afternoon traffic

I did that "mod" of the cut out and side panels as well ...





All seems to work pretty well for now. I have been looking at adding the SPAL dual fan set-up (same thing Ragin Racin is selling) since it can be had for $250. I may do that if/when the stock fan fails.

realcanuk

Lots of great info in this thread. That "cut out" must help a ton by letting so much more air through. I might get ambitious and do that one day myself. I don't have a great pic of it by you can see in this one that I tilted the intercooler as 5 Liter Eater is saying. It does let more air through and I believe helps, but not as much as that cut out.

M M Alexander

Okay, kinda unrelated and random but Canuk ... How in the fork does your radiator cradle look freakin new?! When i took my car apart for the motor swap - my cradle came out in 3 pieces ... I had to reinforce or re-weld every spot on that damn thing



I added in some 1/4" "skids" on the bottom because that area scrapes on everything!



I think I put enough support on it to hold - time will tell though.

realcanuk

LOL... it looks new because I took it off, lowered the rad brackets, and repainted it. By lowering the brackets you can get the rad itself lower, without the cradle being lower and hitting everything in town.






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M M Alexander

If it breaks/cracks again - I'm purchasing a new 1 with plans to mirror your approach.

schpenxel

lol, one of the mounts on mine was broke when I did the SC install. Guess it's not too uncommon given its location

realcanuk

I can't take credit. Copied the idea from someone else but it just made sense. Spacing the cradle down makes it so low. I still used spacers, but very small ones. It is maybe 1/4 inch lower than stock.

miwitte

I think a major part of the reason is the removal of the radiator shrouds as this directs outside air up to the condenser/radiator. Without that, all of the heat trapped in engine compartment is whats being fed to the radiator. Its going to cool better with 95 degree outside air vs god knows what temp trapped under hood. That's why the cutout works its allowing more cool air in. Need a better way to isolate the front of condenser/radiator from hot underhood air or add cutout to supply more outside air. The stock baffle does a good job of that I don't think its that the intercooler is blocking airflow.

realcanuk

Bingo....

That's why I retained the shroud with modifications, and have no heat issues.

5 Liter Eater

Actually mine is tilted like that now and that's what I don't like. I will be modding the frame and tilting it more upright so there is a straighter path for the air to pass through everything and a bigger air gap overall.