Anyone who lives in hot country knows the stock
system is pretty marginal, you can't even run the
A/C without pinging etc.

I know of the LT1 radiator as an upgrade (may be
year -year differences, look for two cores). Are
there other OEM radiators that fit but are fatter?
Who's gone aftermarket and what are the "hot"
options there (performance, price)?

The OE fans seem a bit small for the job and an
upgrade there is likely to help especially with the
A/C on, get more air past the condenser at less
temp rise. Seen people advocate a bigger fan with
the shroud gone (not like it would accommodate
a big fan anyway). Pusher? Puller? Any big'uns
that are street-reliable yet spectacularly effective?

Control schemes - you can program the fans to an
ECT level you want, but seems to me this misses
the point somewhat; Mr. Thermostat needs a
credit line, and turning on the fans is always a
reaction, too late, to the ECT running up. I want
to go radiator-thermostatic and run a single fat-
*** fan to keep tank temp maybe 10 degrees below
thermostat pivot point. Or maybe 20. Who knows
the maximum motor outlet-inlet temp rise with the
'stat cracked full open, full motor load?

Pumps - are there "high flow" LSx pumps on the
aftermarket? Or OE variants that work as a dead
swap on the LS1 F-body, but push more water?
And does pushing more water help in any way,
or just add accessory load?

Airflow - cold air induction setups and tranny coolers
on the F-body tend to shroud the radiator stack.
Different trans cooler mounting schemes (e.g. "Dope"
style) help; lowering the air dam can give more of
a scoop to the cooling air (more hot-pavement air,
oh yeah). Front-breather modifications are pretty
involved from what I gather. Space fore of the
radiator is pretty limited to fit pusher fans. What
kinds of cooling air path mods are worthwhile?

 

I'm interested in this same info. Texas does get hot and it'll start causing the car to ping sometimes on 93.

 

Mine seems to run OK with a manual fan switch and 100* temps with the AC on. I have a 1998, so I have an accurate ECT sensor. With the A/C on and 100* temps(60-70% humiditiy), the car runs at about 190-195*.

What would be wrong with just plugging an upgraded electric fan into the stock fan locations? At least wire the ground and hot to the same stock locations.(I am not well versed in F body PCM/electronics)

I am sure you have probably read about the Meziere Electric WP and how they do not flow as much as stock. I would guess that taking apart the stock WP and "blueprinting" it would be the best bet.

Buy a manual tranny and you won't have to worry about tranny coolers

 

im running the stock 91 camaro radiator (its a little bigger and thicker then the 4thgen ones).. and my stock RS single fan.

it sits at the thermostat with the fan on... even in 110+* heat in traffic....

now obviously it goes higher then the thermostat before the fan kicks on, but as soon as it comes on, temps drop.

before you think about upgrading your coolent system, you should look at what your temps are, then what everything is set for it to be... just because it isnt as cool as you want it, doesnt mean its not capable of cooling it as cool as you want it.

 

I am also interested in this. I have debated if it is worth it or not to go with a 160* t-stat, but I'm not sure if it would help the overall max temp the engine sees. I have my fans programmed to come on earlier, and because mine is an 01 I can't tell my looking at the gauge how much that helps, but I would imagine it helps somewhat. I also run waterwetter, which, from testing in computer water cooling setups....really does improve cooling.

 

Here is my experience. I have a 1989 Trans Am with the L98 motor and quite a few mods. I live in Southern California and it can get quite warm here in the summer. With the stock water pump and radiator the temperature would rise to the 220+ degree area sitting at a traffic light and the A/C on. Sometimes I would have to shut off the A/C to keep from over heating.

Well in my quest for more horsepower one of the things I did was install a Miezerre electric water pump of the 55gph variety. Well low and behold my tempature does not go above 180 degree mark now. It was a side benefit that was totally unexpected.

 

Ah! The fan shroud ensures you are pulling air though the radiator. Removing this means you lost most of the possible airflow. I guess you could seal up any areas between the evap and the radiator so the airflow can't leak out. Thus making it more like a 'solid pipe' from the front of the car into the engine bay.

I live in the South and have had good luck with just the 160 degree stat and stock fan temps. Most of my trips are short enough and opening the thermostat 'early' seems to give enough of a margin to allow me to get where I am going before seeing any cooling problems.

As for increasing the flow rate of the coolant I believe that the radiator's heat transfer to the enviroment is a bigger limiting factor.


Do you think that mods like a 160 thermo stat and modified fan temp could help you OR do you drive too far for a small fix to cover this problem?

 

In general my car runs OK, because it's usually top
down and no A/C. But when I run the A/C my radiator
& fans cannot hold down the temp to support the 160
'stat that's in there. Presently it's stock fans, shroud
and rad with fans on high by 180F. Still not good
enough for summertime with the A/C blowing.
But I have a LT1 rad up on the shelves, some
electric thermostats and a big ~16" fan to apply to
an improved setup.

The other year up to Atlanta, it got to cooking really
bad and last month to JAX I also found a lot of ping.
This after having already added some ECT pullout of
spark advance following the Atlanta trip.

 

Has anyone ever tried getting a B+M tranny cooler kit (mini cooler+fan) and using the stock radiator for only cooling the engine coolant? Possibily, with less heat to dissipate the stock radiator could do a better job.

Are the hose locations in the same place for the LT1 unit?

 

Thats not completly true. While the shroud does ensure you are pulling air over the radiator, it only helps while you standing still. At freeway speeds it acually hinders cooling ability because more air is trying to go through the radiaotr than what the shroud is allowing. Some have "swiss cheesed" the radiator and have seen some gains.

 

You are 100% correct. Let's also note that GM decided to cut the fans after a certain vehicle speed.

I admit I was assuming jimmyblue was having cooling problems at a standstill and not moving down the road as most people don't have problems on the freeway where you would see the fan shrould as a hinderance.

I noticed that the LS1 shrould was flat and against the radiator in many places. I swear I remember older cars (1970's) where the shrould only touched on the outside rim and was shaped like a funnel to allow more useable area!

 

http://www.hotrod.com/techarticles/c...ech/index.html


I know this is meant for old-school SBCs, but look at the pic at the very bottom.

 

jimmyblue

What about what Quickin noticed on his car? I think he has a 98', and basically after 8 years his radiator and ac condenser were clogged with little stones etc.

Now this year it got to be 95+ in Cleveland, and I can't run the A/C either in stop and go traffic, it overheats. I attempted to blow it out with a 125psi air compressor, to no avail (from the engine side out). I'm thinking of trying it again over the winter but removing the radiator. Mine's a 99, and after this many years on the road, it's packed with tiny stones. I have an FTRA but I've never had a problem with it before. But as you mentioned, it does block some flow on the radiator much like a tranny cooler for A4's.

Another thought is the LG radiator, check out opinions on frrax.com. I like the guy's thought above about a 3rd gen radiator, hadn't heard that one yet. Also the link from hotrodmag is neat with the spring loaded flap doors in the shroud.

One last thought; do you have an underdrive pulley? I do for the first time. That can contribute right as the pump won't be flowing as much fluid as a regular pulley?

 

I am digging this flapper idea.



It's nothing radical but really a good idea.

 

Evans NPG+ coolant is always an option, though pricey. Also, if it ever leaks or your water pump goes south, you'd be losing expensive coolant.

I say do a very very thorough flush n fill, with the right mixture of anti freeze to water. Might try 40% af and 60 water or so. And top it off with some water wetter or purple ice. Keeping the cooling system as clean as possible, with a good coolant additive like water wetter.

My next mod will be a 160* t-stat, as I think it would help me more than likely, and that would allow me to program my fans to kick on even earlier. I might also try a few holes in the radiator shroud...or try and see how hard it would be to implement some "door flappers" as well?

 

I had this happen to me on an Aurora. The bottom half of the radiator was completely clogged with fine sand, dust, etc. Though the car didn't overheat, the trans ran hotter than it should and it eventually let go. Something to check.

Al

 

Evans makes aftermarket high performance mechanical water pumps that you may want to look into. Here's a link to a vendor for them if you scroll down on the page. http://www.thunderracing.com/catalog...p&vid=3&pcid=5 I don't know how much better they work than stock, but they are out there FWIW.

Personally, I believe that if you can fit them, the stock shroud and fans are hard to beat. Maybe you could play with some high-performance Spal 12"s but it might be hard/impossible to fit them in the stock shroud since I think the stock fans are kind of integrated into the shroud rather than bolted to it but I can't really remember...the point I want to make is I believe the stock shroud is excellent & designed by the GM engineers who really know what they are doing...maybe they put fans in there that could be possibly (maybe) be improved upon but would just be noiser (which you probably wouldn't mind but the general public might not want a car from the factory w/ real loud fans).

Heat extractors in your hood may help.

From what I remember reading about your setup in various threads it seems your car cools very well...you are just setting the bar very high and looking for it to be able to maintain ~160 or so on real hot days w/ a/c on...point being is you are in a good spot right now...don't forget that. There are a lot of people here who struggle to keep from overheating in those circumstances, sometimes even without a/c. Just something to keep in mind.

Good luck w/ it!

 

FWIW I run straight distilled water w/water wetter in the summer and a 50/50 mix in the winter.

 

It comes down to the heat-exchanger size and surface area for shedding heat, so in theory a larger radiator increases capacity.

There are some ways to get more cooling from the factory system.
A large single fan does a better job of cooling than the dual fans.
Having the fan activate and deactivate based on vehicle speed is great in combination with having it activate at a lower temperature.
It's much easier to always stay at a cool temperature than it is to get hot and then try to cool down again.

Increasing the fluid flow through the radiator will also increase capacity.

Removing a restriction like the thermostat from the path will increase flow and capacity and result in lower operating temps. Two important notes to this is that the bypass valve is attached to the tstat so if the tstat is removed you absolutely must block the bypass path or you will run hotter than before due to 30% of the fluid bypassing the radiator. The other thing is that temperature fluctuates more without a tstat, so a little more work is required on the tune.

Distilled water does cool better than antifreeze, and I normally use it in summer.

 

My 94 fans had rubber flapper doors in the shroud from the factory,LS1's don't, the factory fans are actually pretty good. Griffin, Howe and one other I cant remember make a bigger radiator for a 4th gen, Evans is about to. Cars with some miles on them collect sediment in the lower center of the flues in the radiator which hurts their ability to exchange heat. Clogged fins is the biggest problem, in the condenser and radiator.

And oh yeh make SURE your rubber air deflector under the radiator is on the car DO NOT take it off.


David