04+ what size radiator core do you have? And what's this about bevel springs and nuts

[J57ltr]

I am noticing higher than average temperatures when driving at highway speed. In fact the temp increases as I cruise, all the way to 215*, I am wondering if the GTP's came with 1" from the factory. I know mine was replaced at some point and it is only 5/8" thick. I don't think that this thing is thick enough for use down here where the temps are in the 100+ range and very high humidity. I am just wondering what the normal is for these cars. I am going to get a 1" thick cored one this weekend and change it out.

I have looked at the ducting and don't have anything broken missing or out of place so I should have more than enough airflow to keep the engine cycling off of the thermostat without issue. When I am in traffic the temp runs pretty low in the 197-206 range with the AC running. I also noticed that when I shut the AC off that the temp dropped a few degrees due to not having the heat load from the condenser to deal with but wasn't able to remain at speed long enough to see if it would drop in temp.

Jeff

[Bronco Boy]

.....I am wondering if the GTP's came with 1" from the factory. I know mine was replaced at some point and it is only 5/8" thick.....

When I look up an '04 GTP rad in my parts book, it does show as being 1", and '04 GT is .625". Looks like somebody put a GT rad in your GTP.

[J57ltr]

Figures, I was looking at all the parts stores and it shows both 5/8" and 1" for the GTP, so that's where the confusion started to come in. Then there was an issue where it was mentioning clips for the trans cooler or screw in. I forgot to look at that but I'll look tonight.

Jeff

[Bronco Boy]

Here is a link to the mfg's page if it helps: http://ecat.spectrapremium.com/prod/CU2862
And here is the 5/8" rad: http://ecat.spectrapremium.com/prod/CU2710

I just noticed that different years, the 1" rad shows for the GT also.

[J57ltr]

It was 99* today and I think it got so hot it turned on the fans even though I was still at speed. It got to 217 where the fans turn on then started to drop.

[J57ltr]

The peak temp was 176 on the IAT as I sat in a parking lot to go to the store and left the engine running. Later you can see where the temp is climbing as I maintain speed until it got to 217 which I think the fans came on as it cooled to 212* as I was exiting. The sample rate is every 5 seconds.

[J57ltr]

I keep reading about this specific Bevel washer and nut attachment to the radiator. I also saw, I thought was a flare fitting. Is there a difference on the GP's does this mean if I get a 1" thick core radiator I need to get hoses that attach as well? What's the dealeo on this two fitting business?

Jeff

[99GT2dr]

Do you run the 50/50 premix stuff, or do your own with just pure antifreeze? In my cars, I run mostly water with just enough antifreeze to give it a green tint, no issues with cooling at all.

[bandook]

It was 99* today and I think it got so hot it turned on the fans even though I was still at speed. It got to 217 where the fans turn on then started to drop.

Because there is no "at speed". You will always benefit by fans unless you are going 145, which is the only speed at which the fans shut off.

[Scottydoggs]

im running a 5/8 rad in my GS, its supposed to have a 1 inch. truth is, my temps are the same before and after. your 04 fan settings suck. and they need to be tuned lower.

other than that, your temps are normal up @ 215 ish and all.

[bandook]

Yeah I don't think a rad will do much. I installed the 1" and saw NO difference until I tuned my fans lower. It may now get down to temp a little faster AFTER the fans come on, but that is all.

[J57ltr]

Because there is no "at speed". You will always benefit by fans unless you are going 145, which is the only speed at which the fans shut off.

I have to wholeheartedly disagree with just about everything in that statement. A car moving at 45 mph should have sufficient airflow to cool the radiator and condensor. At 65 there is more than enough airflow and th engine should actually run off the thermostat. Meaning that the temp should rise above the level of the thermostat and open allowing coolant to pass into the engine when the coolant has cooled the engine below the thermostat temp it will close and allow the engine to beat back up. This cools the coolant in the rad well below stat temp and when the engine gets warm enough again then stat opens and allows coolant in. This is the way a cooling system is supposed to work. It doesn't matter the make, model, type of engine, supercharged, turbocharged or whatever.

let me tell you one of my boring ass stories. Back when I had my 78' Diablo (El Camino SS) I had to drive between Houston and Austin, which is a 4 hour drive each way. I had a crack in the front spoiler and removed it. I had replaced the mechanical fan with an electric fan and adjustable thermostat to turn it on. That drive to and from Austin it stayed with the fan running the whole time and ran hotter than normal. Keep in mind I had digital gauges and as you can probably tell I'm pretty good at making sure they stay where they are supposed to be, well because I have always had crap cars. I got home talked to my dad and he said to put the spoiler or one of the front air dams off of another G-body. Well I said he was crazy that thing didn't stick down enough to make a difference. But being my dad and knowing he knew things that sometimes I didn't I went ahead and installed the spoiler back on. A few weeks later I took the same drive in hotter weather and the temp stayed 20* cooler and the fan didn't run at all. All that extra cooling from a barely 2" lower scoop to get air into the radiator. Whodathunkit?

My my point is it should not have to run the fans at all ever when traveling at 65mph there is so much airflow that it shouldn't matter. Ever stuck your hand out of the window as a kid and felt how hard the air pushes on you?

Also i I have been running a minimal amount of antifreeze. About 3/4 th gallon in the system.

So either I have an airflow problem, this rad is too small, or there is a restriction in the system. One thing constantly tells me the radiator is too small and that is the fact that it never gets down below the stat temp even though the fans run full time with the AC, sure it will keep it lower, but it will not cool it below the stat temp at all which tells me it's open all the time.

Also please remember high humidity,very high temps and very close to sea level. What does all that mean? The air holds more heat than it would in other locations.

Jeff

[J57ltr]

Also forgot to add that the cooling system seems sufficient at temps below 90*

[bandook]

I can understand the basic reasoning you are seeing as to why the engine should run cooler at higher speeds. Yes, I have put my hand out the window and noticed that there is more air hitting my hand when i'm moving then when stopped. Sheesh...

My point, the fans do have a large impact on cooling, EVEN WHEN the car is "at speed". I told you I have scan data to prove it, so here you go.


This is my temps when my fans were set to stock values, sorted by ECT.


And here is what my temps looked like after I turned down the fan 1 on temp:


And here are the values I used.



Notice the stock value on the right, which is almost exactly what temp I was seeing in the log. And the modified value on the left, which is almost exactly what I seen after I dropped the fan on temp.

I have had the set temp for fan on even lower, but I chose to drop it about the same as my 195 to 180 thermostat change. I can set the fan to turn on at 180 and my engine will not get any warmer than what I set it to. Even "at speed". Yes, if I keep my rpm's low, the temp will be a little lower, but no where near the temp of the thermostat I'm using. I believe the headers create more heat, and it just gets heat soaked so much faster and just stays hot.

And to further reinforce my point, here is a snip that was sorted by MPH on the stock fan temps. According to what you are telling me, doing 90 mph my engine should be icy cold, right?



But it's just a little cooler than the fan on temp.

So, I rest my case. My only point to you is that lowering your fan on temps WILL see your temps lower, even at speed. I never said that you won't benefit a little from bigger fans or a huge rad, but not nearly as much as lowering your fan on temp will benefit you.

[bandook]

You mentioned that you think the pcm will disable fans when you are going fast. Like I said, only if you are doing 150+ mph.



So GM seemed to realize that fans do effect the cooling capacity of the engine greatly at lower speed, or they would have had them shutting off at 60mph or something.

[J57ltr]

I can understand the basic reasoning you are seeing as to why the engine should run cooler at higher speeds. Yes, I have put my hand out the window and noticed that there is more air hitting my hand when i'm moving then when stopped. Sheesh...

My point, the fans do have a large impact on cooling, EVEN WHEN the car is "at speed". I told you I have scan data to prove it, so here you go.


This is my temps when my fans were set to stock values, sorted by ECT.


And here is what my temps looked like after I turned down the fan 1 on temp:


And here are the values I used.



Notice the stock value on the right, which is almost exactly what temp I was seeing in the log. And the modified value on the left, which is almost exactly what I seen after I dropped the fan on temp.

I have had the set temp for fan on even lower, but I chose to drop it about the same as my 195 to 180 thermostat change. I can set the fan to turn on at 180 and my engine will not get any warmer than what I set it to. Even "at speed". Yes, if I keep my rpm's low, the temp will be a little lower, but no where near the temp of the thermostat I'm using. I believe the headers create more heat, and it just gets heat soaked so much faster and just stays hot.

And to further reinforce my point, here is a snip that was sorted by MPH on the stock fan temps. According to what you are telling me, doing 90 mph my engine should be icy cold, right?



But it's just a little cooler than the fan on temp.

So, I rest my case. My only point to you is that lowering your fan on temps WILL see your temps lower, even at speed. I never said that you won't benefit a little from bigger fans or a huge rad, but not nearly as much as lowering your fan on temp will benefit you.

OK we are not comparing apples to apples here you have a top swapped 01' Impala. I have an 05' GTP and the tunes are totally and completely different. First off the on temp of the low speed fan is 217* and high speed is like 238* I believe. Scotty posted this and backed up what I had said in another thread someone else had problems in. Secondly it is a vehicle that is rated SLEV and to do that they do things like shut your alternator down to 12.5V and other things to keep emissions down. Bill said in another thread that the fans shut down between 35-45 mph while running the AC, after all why do you need fans when you have airflow. Now I am not discounting the fact that the fans will help, my point is I either have an airflow problem or the core is too small or something else I am missing.

The first graph is like halfway through a run I have no idea other than you are running no AC I would venture to guess, and it is a short snippet of your trip

the second one is comparable but your running your fans all the time.

the third graph is a hand picked end of a high speed run where it looks like you are tailing someone going slower than you and holding 3rd gear I would say based on your RPM's

now I am just talking about just driving normally.

The 14' impala I drove was really low on temps and I never logged them. Hell I drove a Jetta TSi and it ran 188 down the freeway. This cannot be what GM intended to have to resort to using fans while traveling down the freeway. I know very well that using fans will keep the temps lower. I just don't think this is the strategy GM intended.

on a side note I went to the junkyard and found that there are 2 pieces that clip to the top of the radiator and cover the space between the rad and condenser. I bought them and added them to the car before I left, the temp went to 200 and stayed there until I exited and went to 203, then dropped back to the mid 190's which is where the thermostat is. Is it the cure all? I don't think so I need to look and see what else is missing. This car was in a front end collision and the the radiator was replaced sometime in the last few years along with the water pump.


And when I say disable I am referring that while running the AC at some point the fans will shut off when it gets to a certain speed not that they will shut off for temp and not come on. I know they will come on while going freeway speeds or my temp would have kept climbing over 217 as it shows in one of the graphs I posted.

[Scottydoggs]

what bandook is showing is before and after fan tuning. your fans are set to turn on higher cause f ing 05 bs.

bottom line, you need a tune.

and it is the same animal. like your sig says a engine is a engine lol im top swapped too. my temps did not change after the engine swap. still the same. and i had the 5/8 th before the engine swap. and even after swapping to a thinner rad while i was running the l67 the temps stayed the same.

[bandook]

he first graph is like halfway through a run I have no idea other than you are running no AC I would venture to guess, and it is a short snippet of your trip

the second one is comparable but your running your fans all the time.

the third graph is a hand picked end of a high speed run where it looks like you are tailing someone going slower than you and holding 3rd gear I would say based on your RPM's

Whatever. Now you are saying I'm being disingenuous to prove some false ascertain you think I'm making? My ac was off in all scans. I keep it off when I'm tuning. I wasn't cherry picking parts of my scans to prove a point. I have dozens of logs that will prove the only point I was making, which I'll say one last time...running the fans at highway speeds will reduce ect's. I know this for a fact because I've logged it and seen it with my own eyes. Before I lowered my fan on temp, my car would NOT go lower than 200°. Cruising, idling, with AC off it would not go lower.

I know they will come on while going freeway speeds or my temp would have kept climbing over 217 as it shows in one of the graphs I posted.

Which adds to the confusion coming through in your posts. Because you just said this:

I have to wholeheartedly disagree with just about everything in that statement.

To me because I said:
"Because there is no "at speed". You will always benefit by fans unless you are going 145, which is the only speed at which the fans shut off. "

Now I'm so confused I can't even make sense of what you disagreed with lol. You "wholeheartedly disagreeing" with my post is the only reason I went through all the trouble proving my claims with data.

Bottom line and I'm out...your car runs hot because you live in a desert and drive a heaton. Tune your fans or go through all the trouble of installing a larger radiator... Like I did...and see no improvement.

[bandook]

And you ARE right about the table to turn fans off because of AC. But it is set at 75 mph and only turns off if ac pressure is high...or low. I don't know exactly what the conditions mean because I don't know a lot about the ac system...so many variables with it.

I would venture a guess that ect tables override this ac condition. Could be wrong but I would imagine keeping the ect's in check takes precedence over the ac fan control table.

[J57ltr]

I have never seen a system that couldn't maintain temp when running down the freeway without using fans. I think you guys are just used to it so you get around it by using the fans all the time. My SC has a horribly small but thick radiator. That car never got over 200 even in the hill country, and the fans never ran, unless I dropped below 35 with the AC on. Now that car and several others I know backwards and forwards I can turn on the high and low speed fans had LED's to moniter them when they were on, so I know that car. My 95 Taurus is very close to the same electrical scheme and still has the digital gauge in it It never had temps that high. My 97' Park Ave always ran under the middle on the freeway. Haven't checked my wife's car but the other 2 cars I mentioned as rentals were very low as well on the freeway. Hell I drove the Impala 6 hours to Shreeveport Louisiana. I'll have to find the pics but I drove that car and logged voltage because no one believed that the voltage fluctuated and the guy ended up putting in another alternator for no reason. I have pics of the phone during that trip. I'll review them and see what temp it ran at. All I'm saying is if GM did this on purpose, then it is piss poor engineering.

Jeff