when driving on traffic on a 110 degree F day the oil temp reaches 210-215 degrees F and the coolant temp is 230-235 degrees F.

when driving on the free way it is okay, oil temp is 188 and coolant is 203.

i thought about installing a vented hood if it will help extracting the heat from the engine bay. anyone has installed a vented hood? does it help reducing the oil/coolant temps on stop/go traffic?

how effective installing a vented hood would be? shall i go for it or just save the money for a dewitts radiator and dual fan upgrade?

car is H/C Z06 with 160 T-stat.

 

for whats it worth...

a BONE STOCK standard C6 (no oil cooler)
Stop and Go in 110* (Phoenix az)
Engine temp 200*
Oil 230 -245 (romping will bring it up to 258)

Gm has stated that the Oil can handel 290 all day long and be fine.
In looking at your numbers the 200 engine temp would be your goal.

If its ok when driving, and making sure your system is in 100% working order (no crap in the schroud, no air bubbles, clean connectors on the fan). Then your 'problem' is not enough air flow/cooling capaticy at low speeds.

That means a Dewitts Radiator would benifit you greately.

To go with a dual fan on that unit is a tough call. The newer fans are progressive in speeds and communicate back to the PCM, while the Dual Fans (C5 circa) are a simple on/on, off/off, or one on and one off. A little bit of redneck wiring has to be done to use Dual fans. Not all bad per say just not plug in play.

In my C5 I had a problem with High Oil/Engine temps during the summer months and I did a trick of removeing the rubber seal near the windshild. The air flowing across the hood and up the glass created a vaccume and 'pulled' out heat from teh engine bay.
My point in telling you this is the engine temps were only affected a little, but the Oil temps dropped by 10*-12*.
assuming the same with the C6 I bet the vented hood helps the oil more than the engine temps.


..but this is just my opnion

cheers
cahd

 

Someone on the forum not to far back cut a hole in the top of there hood to help with the same problem you are having. I believe he claimed a few degree decrease but I will try and locate the post.

If I were in a very hot climate like you I would install a new radiator and then a 160* thermostat and you will see a huge difference.

 

A really big radiator like Dewitt has. When you do that turn the fan temp down also.

 

if i go with Dewitts radiator, does it mean that i don't have to bother about replacing the stock hood with vented one? or shall i do both, radiator and vented hood?

will the MTI style hood (has louvers on each side) be a good hood for this purpose?

 

I replaced my stock radiator on my Z06 with a Dewitt's, and it made no difference in the temps during stop and go traffic in the hot summer months in Phoenix. I believe there is just not enough air flowing through the radiator in traffic. I looked at adding the Dewitt's C6 Dual fan upgrade, but basically all it is; is just a dual Spal fan with brackets fabricated by Dewitt's. All they supply is a generic Spal wiring diagram. So like a previous poster said....not plug and play and you will have to splice into the factory wiring. Highway driving and on the track, the radiator does make a difference. And yes, I do have my fan programmed to come on sooner than the OEM program.

 

I'd do a tune and set the fan to come on much sooner. When my non- ZO6 2006 LS2 was tuned, my fan was set to come on at 196, and I have a 180 thermostat installed. So my coolant temps stay under 200 all the time even in inland So CA where 90+ summer temps are common. My oil temps will get to 210 max usually.

 

Setting the fans to come on lower will help. Vents will let more air flow thru the radiator by lowering air pressure behind the radiator. Be sure to choose vent locations where there is not high pressure above it as that will push air in instead of extracting during times when car is moving.

You can also remove the panels that block the front fender vents.

 

I ran the MTI (Hi-tech) hood all last year with no heating issues. Back to stock hood and now it gets hotter but not overheating. For your oil temps you need an oil cooler. Hood will not help in this dept that much. I saw a 20-30deg drop in oil temps by just adding a stock Z oil cooler; great mod.


I have a Vararam, Z oil cooler, stock a/c condenser and C6Z radiator up front so airflow is a challenge in traffic. Once rolling temps drop quickly. A vented hood like the Hi-tech will definitely keep the bay from getting stuffed with hot air. I'm running about 15deg hotter this year than last BUT its been much hotter and more humid this year.


Hope this helps.

 

Do think about this.

Most of the race cars would like to see 180-200 degree coolant temps (although I have seen them run 220-230 for short periods), oil temps are fine in the 250-265 range. It can run all day like that at race pace. A few moments of oil temps hitting 290+ is ok as long as it is a good quality synthetic but you need to change it after that weekend's event.

Street cars are going to see hotter normal coolant temps because you have things like emissions and clean burn cylinders to deal with not to mention cats, so in general things are going to run hotter. 235+ water temps start to make me nervous but I have seen them go past that.

In traffic and there is little to no air flow, a vented hood is not going to do much, it will allow some of the air under the hood to get out, but you will see it's biggest benefits when the car is moving. Not only to help draw air through the radiator but also to help reduce front end lift. Again, a good thing.


If you already have the thermostat in the car, has the fan settings been changed? This can also greatly help if it has not been done as it does need air flow to cool.

If that has still not worked, then a larger radiator with more physical cooling will also help bring down the temperatures, again combined with the thermostat and fan settings.

Oil temps may go down slightly by taking some heat out of the engine, but if you see extreme oil temps then a oil cooler, either built into the radiator or separate would be the way to go. For the oil temps you are seeing, I would not worry about it.

 

I have a base c6, not Z06. I think you will see good results with an electric water pump.. it'll keep coolant flowing well at low RPM.

 

I would agree with it moving water at low RPM's but they have a hard time at higher RPM levels as the pump moves at one constant RPM all of the time, and does not change like a belt driven unit. Not as good for a road race car, but it depends on the use.

 

Exactly what I learned first hand at Little Talladega a month back. Temps steadily climbed in 100deg weather just 2 laps in. Had to pit and call it a day as there was no hope. Went back to a mechanical pump since track days are at the top of my to do list.