Live in New York and winter can get real cold. Question - my son has a 350. Team G rised intake, 750 DPump Edelbrook, 10.5 compresion, 3500 stall, turbo400 with a 350 tail and a manual valve body, and a 411 posi rear. Using a 4 core rad and tranny cooler feeding back into Rad.I looked in the archievs and found a couple of posts regarding a 20 to 25% mixture of coolant to distilled water and water wetter. What would be a safe mixture for cold weather? Should he use a higher coolant to water ratio in winter and drop it down in summer?

due to his set up, engine runs on the high side to begin. He uses it as a daily which entails local streets and highways.

any dvice would be appreciated.

Kevin

IIRC, a 50/50 mix is good to -34 degrees F.

Yeah, if your worried about cold, then 50/50 is a good mixture. Only run less coolant if you are having some overheating problems like in the summer. I was having overheating problems and I used water wetter and didn't even notice the difference, so that is up to you.

-Yellow 69 chevelle

buddy is right a 50/50 mixture is a good start. But make sure you get the dextron II (orange stuff) because it is more compatible to aluminum i.e your intake and it lasts longer. However, anti-freeze has a higher boiling temp. than water so I don't know what he is talking about when he says to add water to the mixture to prevent over heating. WHAT THE HELL ARE YOU DOING DRIVING THE CAR IN THE WINTER FOR ANY WAY?

WAIT.......DON'T DO IT!!! Add dexcool that is! I have to take exception with the last poster that recommended the "orange" or red stuff. This is also called "dex" and is NOT compatible with any green or yellow antifreezes and will give you maintenance fits. You cannot run this in any percentages other than 50/50%!

Unless you are starting with a completely fresh fill (like new system) or are already using dex do NOT switch. And the ethylene glycol (green or yellow) today is just as good at protecting aluminum parts as the red is.

Read here for more information... http://www.inccn.net/jscooling.htm

To answer you other question, yes you can run less % of antifreeze to distilled water in the summer and put just enough antifreeze back in during the winter to cover the minimum temperatures that the car will see.

Thanks HOTRODSRJ....see new topic i just posted.

HOTROD, never mind the new topic.....just mixed screwed that up, anyway, put a wuart fo green in w/ red in my 2002 Caddy...yesterday, saw your note...Caddy's in garage...the 2 don't mix...gettting a $109 flush/fill! Better than screwing up enginge!

Orange coolant DOES NOT last longer than green coolant!!!! This is true for older cars that don't have a sealed cooling system or in other words a vented overflow or no overflow at all. What happens is the constant mixing of the orange coolant with air breaks it down quickly and turns it into a nasty slime that it tough to get out of your radiator. Just ask anyone with a newer jimmy,blazer,sonoma etc and they will tell you what a mess this stuff creates when it is not flushed and changed reg. ie: every 30k miles. There is no benefit to changing from green to orange coolant and in fact it is more of a headache. Many of the newer cars in our shop that have this slimeing occur have been flushed and changed over to green, end of problem.

I learned alot the past week on a personal level. The Dex is for newer cars only, the viscosity is less and that's why they use it because the fluid tubes are smaller nowadays.....better flow. They definitely don't mix. You can use dex in an older car but there's no advantage. Onthe other hand, depending on make/model/year....Dex is a must for newer models. 50/50 is generally a good rule of thumb, however, it will run hotter than 100% water....water dissapates heat better than the anitifreeze.....so yes run less antifreeze in the summer if you overheat at long idle, like I do. Of course, here in Ohio....you'll want some freeze protection if you want to keep the block you have so 50/50 is essential....I'm guessing 25% antifreeze may be the best way to go in hotter states.

And finally, I'm considering trashing the "clutch fan" on my 67 Chevelle 396.....I've come to realize it serves no purpose but to let the car heat up quicker....since I don't drive it in the winter, what the hell do I care? It's probably the biggest problem with my over heating at idle as opposed to no problem overheating when moving....there just no way to tell how well the damn thing is working but it can't give you more air flow than a straight fan. While I'm at it, I'll probably switch to a 6 or 7 blade set-up from the 5 I have now. Driving through long lines at cruises can be probelmatic and you'll need all the air you can get. Too cool and you'll take away performance from a big block which should run around 200 degrees. Took a week nut I actually think I know what I'm talking about!

dafr3333, A heavy duty fan clutch and a seven blade fan is the ticket for stop and go cooling. Don't believe it stick your head in the engine compartment with one of these and again with anything else. Feel the difference?? Just don't stick your head in there too far. Will agree if one is after pure brute force and ignorance that an electric setup is the way to go if one wants to put the greenbacks to it. Just another opinion!

Alot of the guys here run clutched fans successfully and like them alot. I for one do not. The reason is that you can never tell whether you are getting the full engagement or not until it's too late? And, the aftermarket clutches that are made today are kind of a "universal" replacement. GM had over 60 varients of the clutch mechanism depending on application. So, many new clutches today DO NOT conform to the original specifications for most applications.

I am now a converted flex-fan guy. Yes, I said flex fan. I never used one and was absolutely against them due to the shoddy attachment designs and ineffectiveness. That is until Derale came along with a great new technology design. Derale has a heavy duty series that is made as well as the standard fans and uses much improved connections and moreover high quality stainless steel blades that allow higher attack angles at idle and slow speeds, yet give up their angles at high RPMS. I run a 17" Derale #17217 on my 69 Camaro, 400hp+/air/traffic/heat..and still flog it to 6500 rpms on a regular basis. They are not noisy either and my temperature gauge stays on 180 all day long.

My friends 69 Chevelle SS396 w/air would not cool here in Atlanta. We dumped the clutched fan and also went to a 68 shroud and added a 18" Derale heavy duty and he's a happy camper today!

Just another alternative to meantion...that's all.