SuprJames

by going to an aluminum radiator? Follow up from my previous thread "best place to buy an aluminum radiator." My car has a problem about running below 190 degrees on 85+ degree days (everyday in Flordia). The spals run all the time. Will an aluminum radiator fix this?

AlwaysWave

What temp is the on/off sender? Most I've seen are preset to turn 'em off at 185 or 175. If you're using a t-stat close to the sender rating they are possibly fighting each other.

Going beyond that, the cooling system has many components, any of which will can keep you running hot. Radiator clogged, lower hose collapsing, loose fan belt, etc.

If you can get the fans to turn off automaticly, about a 185-195 running temp is actually a good range for minimal engine wear and fuel efficiency.

The Money Pit

I dropped about 30 degrees with mine.With the stock radiator and a fresh rebuild on the 406 I ran 200-220.Put in the Griffen and now it runs 140-190 max.Last August in 95 degree heat it maintained 190.

0Tom@Dewitt

There are two different temp switches offered by Spal and I don't know which one you have. The settings are 195on175off and 185on/165off, so both of these "off" settings are lower than you can get with the present system. As mentioned, the thermostat can also fight this function. Since you are already over your stat setting, you have max'd out the system and the current radiator can do no more, even with the fans running continuously.

To answer your question, most people tell me they dropped 25-30 degrees with a new aluminum radiator. Some higher, some lower....but 25-30 is very common. Here's what I usually recommend:

First, get the "direct fit" aluminum radiator from us of course, then install a good 170 stat. I know 170 is odd, but 160 is too cold and 185 might not work. Install the Spal 195 switch. This way, the stat opens at 170 and starts to cold, but no fans yet. Temp rises to 195, fans on......Temp drops to 175, fans off and coolant still flowing. Now if it drops any lower, the stat will modulate the temp at 170, if the temp goes up, then the fans come on again at 195 and we start all over.

AlwaysWave

Tom, don't you mean a 180 t-stat? Problem is this. The t-stat has a repeatabilty tolerance of +/- 5 degree and the thermo switch of about +/- 10 degrees. So on the cool end (worst case) the thermo switch may be looking for 165 and the t-stat is closeing at 185. Hence the problem.

Those tolerance and repeatability numbers were given to me by Moroso (T-stat), Painless and Spal (thermo switches).

I'm trying to find a thermo switch that turns the fans on at about 205/210 and off at 195/190. That will avoid overlap of the 180 t-stat.


[Modified by biltogo, 7:27 PM 8/1/2003]

SuprJames

My spals are computer controled. I set my temperatures through a program called Calmap on a laptop. Right now I have the "on" at 200 and the "off" at 190. The fans rarely go off, but the temp never rises above 210. I'd like to be runnning at normal temps. All the hoses, engine, waterpump are all new. Even the radiator is only a couple years old so I doubt there are any problems there. Think my 10.3:1 compression is just going to run hot with that radiator. Two years ago I didn't plan on going to a new engine so an aluninum radiator was not a necessity. I'm certain runnning 20 degrees cooler will eliminate my problem. I'd have to look up what size thermostat I'm running. I have no idea. Thanks for the suggestions and info!

I seriously might get one of your radiators, but I want to konw what makes your radiators better then Summit's cheapos? That's quite a bit of extra dough for a little convenience. That's not a challenge, just a friendly question.

0Tom@Dewitt

You're exactly right! We need that and I am bugging spal to make one. That's why I standardize on the 195 switch because the 185 will NEVER shut off. But in your example it's possible the tolerences could also be in your favor and work fine. The only other thing I can think of is to buy another brand of adjustable switch and set the temps you want. I think painless makes one.

0Tom@Dewitt

It's a good question. The first thing one has to consider in buying a "universal" is how much is their time worth converting. Many of the forum people are making pretty good money and if you spent 3-4 hours making the universal radaitor work in your car, then did you really "save" money? A lot of these conversions require cutting shrouds or welding brackets, and/or custom hoses so the connections line up. Maybe a few years down the road a hose blows up and your hundreds of miles from home. The local parts store has the stock factory hoses that fits your model corvette but guess what, not yours. I find it easier to keep everything as close to stock as possible.

Now for the product differences. Many of the replacement aluminum radiators use "fabricated" end tanks. This means they take a piece of flat sheet metal and by way of bending and welding create a "box" that fits on the end of the core. We invested in tooling (metal dies) that form the tanks into shape. This provides a seamless tank, with ribs for strength, and the factory look.

The upper & lower channels on factory C3 have four bends in them that make the core very strong. We duplicate this pattern for the same reason but it also provides a "standard" when thinking about adding electric fans. You see if everyone used the same channels, then everyones fans would fit everyones radiators. Our dual fan kit is designed to fit the stock copper gm radiators, our direct fits, and griffins. No one else uses the channels, so they are the odd ***** that force you into buying $150 worth of brackets to mount the electric fans because they didn't make the radiator right.

Hinge clearance is an issue on C3's. You will notice that many cars have the upper left (driver) tank with a flat spot. This is so you don't have any trouble closing the hood.

Many "universals" do not include transmission coolers and some of the other guys charge $100 more for automatics. We don't change anything.


[Modified by Tom DeWitt, 9:04 AM 8/2/2003]

Black68Vette

I'm using the good ole fashioned fan and factory radiator, but just connected "straight" (no clutch) and even after hard driving I've never seen it over 160 degrees....

You might want to install a bigger up front spoiler to help funnel more air into the radiator.

SuprJames

[QUOTE]
It's a good question. The first thing one has to consider in buying a "universal" is how much is their time worth converting. Many of the forum people are making pretty good money and if you spent 3-4 hours making the universal radaitor work in your car, then did you really "save" money?[QUOTE]

LOL, I'm a 23 year old guy just out of college so I'm definitely not like any of the people on this forum with money. I'm still trying to pay my parents back for all the money they've loaned me to build this car! Does your upper radiator hose outlet really bend out like that? My upper outlet goes straight into my upper A-arm barely leaving room for my cool flex hose. Do stock 82' radiators do that? That could explain the beating the hose used to take from the altenator. Thanks for taking the time to respond to my posts!

tabbruzz

Can you explain this to me?? I have a problem with my car hitting about 220 in the summer heat. Are you saying you simply removed the fan clutch and mounted the fan to the pulley? What was the temp diff with and without the fan clutch??
Thanks,
Tony

Black68Vette

Theres an adapter that goes in place of the clutch, pretty much just a straight block to maintain the same distance from fan to radiator.. It was like that when I bought it, so I dunno how it was before that. Now I will admit too, that given non working gauges (soon, soon they will work!) I'm measuring temperatire with an infrared sensor setup at both the radiator and thermostat housing. So it could be a little higher than that in water temp, but thats even after an hour of running, so it should be pretty close. Thats even with letting it sit still in the garage running for 20 minutes, not even rolling... I don't have AC or power steering, so theres not much stuff in the way of airflow, and not much parasitic power loss at idle either, so maybe that helps, and I have sidepipes which I also believe helps get rid of some engine compartment heat.

0Tom@Dewitt

The corner picture is from our A66M model (66-68BB) cars. The 77-82 upper neck IS straight. Here is our A77






[Modified by Tom DeWitt, 5:40 PM 8/4/2003]

SuprJames

Thanks again for the response. It occured to me just now that instead of bugging you with all these questions I could've simply checked out your site. I'll probably be giving you guys a call this week as soon as I figure out how much spare change I have :yesnod: .

tabbruzz

Great thanks