schpenxel

What kind of ambient temps are you seeing?

Blackonblacksls

High 80s

schpenxel

Nice, sounds like it's doing good then. Wonder why so many people have temp issues if the smaller radiator you're using works fine.

Blackonblacksls

No clue, I wonder the same thing.

But my last car was an iron lsx block with a stock radiator and I ran a completely stock cooling system and never had issues with that one either..

I had the car out at the local Quaker steak meet tonight. On the quick stop and go drive there and back, I don't think it ever even got to 190..

ajrothm

Congrats man!

Have you tested it on a 90*+ day with AC on? If not, post back when you do.

I was at the Quaker steak meet and saw you pulling out. For comparison, driving my car all evening last night, I never went above 180*. However, it was only 83* outside and I wasn't running the AC.. 90* and AC on is a whole different ball game..

Yesterday during the day, it was 86-87*, I was running my AC all morning and into the afternoon, also made some highway pulls, I was idling at 212* in traffic...no doubt it would climb the longer I sat there... (More then 15 mins), and no doubt on a 92-95* day, it would run at least 10* hotter...minimum..


BTW everyone loved your oil cap.....lol

Blackonblacksls

Yeah it got a lot of attention, I think I'll probably end up leaving it there for a while just so everyone knows it's mine

neverstop

I think it helps on your turbo setup that there is basically nothing behind the radiator obstructing air on the back too. On most vettes of course the radiator angled back with abs box, etc behind it I think really impedes air flow and is even worse on the C5s. Seems like opening that up on your setup made a huge difference.

fun looking setup though!

ajrothm

OK, here comes round 1000 with my cooling system war...

I decided to try the 12" Spal EXTREME fans, I have not been able to find anyone running them besides the 11" versions that D3 uses...so I figured I'd crash dummy it for the class as usual...

Here they are:


Comparison to the 12" Spal HP fans (Dewitts fans)




Mounted them up and soldered the C5 pig tails on them


They are a tight fit... I did have to trim the shroud some on the passenger fan to clear the blower.


Clearance to the sway bar....



Initial test seems very promising...but I won't brag much until I get a better test in... First it was only 91* today, so not that hot, but very humid.

Second, about 30 mins into the drive, my alternator started glitching out and dropping voltage so I had to turn around and limp home.... That being said, I ran the car for over an hour in city streets, lots of idling, AC on blowing 40*..... When the alternator was maintaining voltage, it never went over 210* (normally it would have been 220+ on the same drive)... and even after the voltage dropped to 11.6v, the highest temp I saw was 214*(but I did turn the ac off because I knew I was limping it home)...

Back home, idling in the driveway with the AC on, it SAT at 210* and would not climb...(while I was messing with the alternator)..

This is definitely the best it has ever done temp wise... I think/hope once I get the alternator issue resolved and get constant voltage to the fans, there is a CHANCE it may actually stay under 220* idling in traffic on a 95* day with the AC....which is a freakin miracle for this car if it happens.


I will say these fans pull a lot of air, make a lot of noise and pull a LOT of amps...they are about 30 amps each while running.... So you better have a bad *** alternator, big cables etc etc...

I'm optimistic.... We'll see....

schpenxel

That is awesome. I think someone brought it up earlier, I wouldn't hesitate to bump idle timing up a bit too, can't hurt to see if it helps at all

Hopefully these fans will finally get your temps under control

95wht6spd

I hope that fixes it.
Did you have the same oil cooler before the 402, or did you install at the same time?

ajrothm

I added the oil cooler later on....but it's been on for the last couple summers. It knocked 20* off of the oil temps on average, but made no difference in coolant temps...nor did a LOT of stuff that people recommended..

These fans are the ONLY thing that made any measurable improvement in temps.

I tried another test yesterday, 91*, city driving, stop light to stop light, temp stayed 205-208*, then about 30 mins in, my alternator started glitching out at idle again...so the temps came up pretty quick with only 11.6-12.0v running the whole car.

I'm gonna send the alternator in this week for repair so I won't be testing the fans/temps again for a couple weeks. The jury is out on if they will "solve" my heating problem, but they DEFINITELY made a noticeable inprovement... I'd guess 8-10* on average at idle.. At a couple stop lights, it would actually cool down at idle...

We'll see tho. I'll do a good comprehensive test in a couple weeks. They definitely pull some serious amps though, roughly 30 amps each in their restricted state(high static pressure)..FYI..

Turbo-Geist

Glad to see you are making some progress Alan and really appreciate you testing these out.

I'll put my recent experience out there after some tuning today.

Cooling related modifications:
427 sleeved LS2 with 9.75:1 compression
TTiX Turbo Kit with no oil cooler
Full size Dewitts radiator and SPAL HP Fans
75/25 water/coolant mix with purple ice
TrackSpec T1 hood vents

Ambient temps outside today at 1:00pm were 100F

Just cruising around:

IATs: 120F
Coolant: 207 to 214F
Oil 255 to 260F

Made some WOT pulls to 4,000rpm plus stop and go traffic:

IATs: 104F due to meth injection cooling
Coolant: 220F
Oil: 265 to 270F

Pulled in the garage and let the car idle plus revved it up a few times and right before I cut the car off:

IATs: 135F
Coolant: 230F
Oil: 270F

This is without A/C; I still need to charge the system.

I just wanted to let you know my experience with some true street driving in the Texas heat at 1pm. The total run time was about 1 hour worth of driving. I was doing drive-ability tuning plus lower rpm WOT pulls. The car spent some time sitting while reviewing logs and using real time tuning plus turning it on and off to flash new tunes.

Turbo-Geist

More data from the same day, but at night with 86 degree ambient temps.

Low speed city driving with stationary idling and speed less than 30mph:

IATs: 130F
ECT: 218F max
Oil: 260F max

Cruising at highway speeds:

IATs: 95F
ECT: 194F
Oil: 244F

I just put a new coolant cap on the car and plan to re-test to see if there is any difference.

ajrothm

Those temps don't sound too bad.. However, AC on is another ball game.

Better start shopping for fans and a big alternator.

I'll be testing more next week as well. My alternator is on the way back.

One tip, make sure to run a 2/0 ga charge cable from the alternator to the battery. If your charge cable is too small for the amps you are pulling, it will smoke the diodes... (Ask me how I know).

zrtman1

Any progress?

Similar problem here. LS3 Alum block, dewitts cutdown and spal fans. No problem cooling until AC is on. Without AC on temp creep up to 210 in traffic and pretty much stays there (96deg days high humidity). With AC on in traffic or sitting in parking lot temp will slowly creep up. At 225 I shut AC off. Temps will drop surprisingly fast.. right about the time its gets down to 210 the inside of car is getting hot and I turn AC back on. Temps will drop much quicker than they will rise.

I have been working on sealing the fan shroud to radiator. Any small openings I could feel it pulling air (hot air from engine compartment). I also have radiator sealed to frame and top of A&A shroud sealed somewhat to radiator. It is a work in progress and seems to be helping. I think the key is to be sure all air is from front and not recirculating any hot air under hood.

I have the stock alternator also - so when it is heat soaked the voltage is not that great. I know this would help me to increase volts at idle.

I was also thinking of adding a spal pusher on the ac condenser (worse case).

ajrothm

Not yet. I have my alternator back and my 2/0 welding lead cable here and ready to make the charge cable...I just need some time. I'll probably tackle this on Monday morning and be road testing Monday afternoon.

Yes, AC is the deal breaker for sure.... Pretty crazy how much heat it generates and how it cripples the cooling system.. When I had the 12" HP spals, without AC I would never go over 210* on a 95* day, usually never over 205*...but man when that AC is on...look out.

I'm cautiously optimistic that the new 12" Extreme Spals made a significant improvement, more so then any other cooling system mod...

StuntHeavy

Right there along side you guys. This heat in houston is killin me.

My car seems to be fine at idle, but the longest I've ever idled it with the new build, without moving was 20 minutes. My heat troubles come actually moving down the road.

Working on shrouds tonight, hope to test them tomorrow.

YoungRedZ

Just want to chime in with my numbers. I have an A&A kit installed with no other cooling mods done. Completely stock radiator and fans. I live in Phoenix, so we get some pretty brutal summer temps to deal with. Yesterday it was about 112 outside on my drive home from work. My drive home is about 12 miles, all city. While traffic was moving, my car was running right at 215-217. I did catch a few lengthy red lights and my temps raised ten degrees to 227. Once I got moving again things would settle back down to about 217-220. Mind you, this is with the AC on full blast.

I'm not too worried about these temps during the summer. Considering the air temp was over 110, the temp near the asphalt where our cars breathe has to be higher. During the other seasons, my car does perfectly fine rarely getting above 205. However, I do want to get a DeWitts cut-down with fans and an integrated oil cooler. Even though I'm not too worried about my temps in the summer, I do think there is room for improvement.

ajrothm

I would not change a damn thing on your car. Your coolant temps are great for that ambient temp.

You put a big thick Dewitts in there, and watch your temps climb at idle...

Most fans are not strong enough to pull good air flow through the thick core on aftermarket radiators when there is an intercooler sitting in front.

Leave it alone!

Lots of people people here running stock radiator and fans and not having nearly the issues many of us have... At least not at idle.

Big thick radiators and aftermarket fans may not be much of an "upgrade" honestly...

schpenxel

I've wondered about that a lot.. Whether an "upgraded' radiator is really a better upgrade vs. stronger fans.