Grille block in Phoneix AZ summers

[alanchap]

Has anyone had any experience with using a grille in the phoenix area? I drive a lot for work in stop and go on the freeway and on surface streets. I am concerned about overheating in the summer. I drive a Scion xB and there is no temp gauge so I cannot monitor the engine temps. I will probably need to install a temp gauge if I do this. I am thinking of blocking the upper grille and partially blocking the lower one.

Has anyone done this to a xB and if so were there any gains?

Thanks
Alan

[GasSavers_BEEF]

here is one that is seeing over 40 mpg.

http://www.gassavers.org/garage/view/23

I think the user name is jangeo but I am not sure.

be careful in pheonix, I think the grill block will definitely help in the winter but keep an eye on your temps during the summer

[korax123]

Yea you might be able to get away with a very small grill block in the summertime. But I would make an easily removable one to put on for the winter time.

[GasSavers_Mr_C]

If you do decide to do something, get a scangauge and monitor your temps first before you make the change so you have a good baseline, then watch really carefully when you start blocking it. I highly recommend monitoring it with a digital gauge so you can see small changes easily.

I blocked my entire grill, but since I am in MN, I didn't think it would be an issue. I made it 5 miles down the interstate before the temp gauge was climbing FAST. I pulled a lot of it off and it was better. Then I put the scangauge in and realized it was still getting warm enough were the fan would go on low frequently and high occationally. I have continued to remove more of the block to reduce the fan requirements.

You definately want to figure out how warm it is running. If you have a way to monitor your electric fan (I can with a scangauge on my ford) you might want to check that first, because if the fan is already running frequently on the highway, any grill block will probably do more harm than good.

-Mr_C

[ziddey]

I've got a vw fox, which has a tiny radiator on the front driver's side of the car. I've got the grill duct taped up. There's still a small opening on the valence though. Intially after putting on the duct tape, I noticed that prolonged heavy load on the highway (long stretch of uphill) resulted in the temp gauge climbing higher and higher. Outside temp was about 85'f.

But as it turns out, I only had about 3.0-3.2qt, from the normal 3.7-4.0qt. Topped up to 4 quarts and temps don't climb anymore. But fuel economy sure went down. Lost almost 3mpg with the right amount of oil.

So how's this for a new way to get economy . Use less oil, but install an oil cooler.

[thornburg]

Originally Posted by ziddey

I've got a vw fox, which has a tiny radiator on the front driver's side of the car. I've got the grill duct taped up. There's still a small opening on the valence though. Intially after putting on the duct tape, I noticed that prolonged heavy load on the highway (long stretch of uphill) resulted in the temp gauge climbing higher and higher. Outside temp was about 85'f.

But as it turns out, I only had about 3.0-3.2qt, from the normal 3.7-4.0qt. Topped up to 4 quarts and temps don't climb anymore. But fuel economy sure went down. Lost almost 3mpg with the right amount of oil.

So how's this for a new way to get economy . Use less oil, but install an oil cooler.

The listed "oil capacity, including filter" for a VW Fox is 3.5L = 3.698 quarts. I wouldn't put in more than 3.7, and I'd probably use 3.5...

[ziddey]

hmm, I guess shift the numbers down by 0.3 then. I fill up to the top of the dip****, which I assumed was 4qt. I always get those 5qt jugs so I figured I was doing around 4qt.

[trautotuning]

I have been in 100F here in Texas and my car is doing completley fine.

This is with a almost total front grill block and a front undertray... So I say you should be fine most radiators are made HUGE.

[GasSavers_Gollum]

A huge part of how well a cooling system works isn't just the size of the opening, if that were the case my Z would NEVER overheat.

At higher speeds (35mph and up) how well the radiator is sealed to the core support, how open the core support is, or how well the opening is ducted to the radiator and sealed to it are the biggest factors. You can use an extremely small opening with a big V8 with only a moderate aluminum raditor if the duct work is done right.

I'm not a huge fan, so don't think me redneck, but look at nascar designes. Very small openings, and they're running up at 180+mph generating a huge strain on and engine that's pushing a lot of HP. How do they do it?

1) Duct work. This is the most important

2) Large enough radiator for the given HP range of the engine

3) Removing as many obstructions in the cooling system as possible.


Now, for low speed driving, like stop and go (very hard on the cooling system), you might need a larger fan that can push more CFM. Reason being is that less free air is availible and the fan needs to create more vacuum in front of it in order to create the same CFM flow through the raditor. Make sure it has a nice tight seal to the raditor too.


Also remember that if you're not too worried about subfreezing temps, you can run more water than 50/50 in your mix. Water cools the engine better than anti-freeze (aka coolant). The main purpose of anti-freeze is to keep the water from freezing, as the name implies, and also to prevent corrosion. I've run up to 80/20 here in california with no problems. I've also met guys who run 90/10 in their hondas which have tiny litter radiators. Water also cools down easier than coolant. The biggest factor as you get down to those ratios though, is boiling point. Antifreeze also raises the boiling point of your mixture, so overheating can become dangerous. Boiling water doesn't cool the engine well, causing a cascading effect once you start to overheat.

[GasSavers_Hal9000]

I grew up in Phoenix and I used to overheat all the time.... The car didn't do too well either.

For those uninitiated to Phoenix weather. Summertime highs during the hottest months are routinely in the 115F(+) degree range and 120+ isn't unheard of. Those are whats reported on the news, and I've long suspected that the reported temps are a bit optimistic. I routinely saw back porch thermometers that ran 5-10 degrees above the reported high temps when I lived in the Valley. Sitting in traffic with your AC running is very taxing on even the best cooling systems.

Alan, The first thing I would do would be ask the dealership if they have a higher capacity radiator than what is in your car. If they don't, there are a number of local shops that can re-core your existing radiator to increase the capacity and cooling area. That will help.

Second, I'd start by blocking the air intakes that are closest to the ground first. If you're going to block any airflow, block the hottest air (coming right off that hot asphalt) first.

If you DO choose to run less than 50/50 antifreeze like Gollum suggests, get a higher pressure radiator cap. The additional pressure will raise the boiling point of the coolant somewhat and get back some of what you've lost on the top end. In addition, get the low temp thermostat so your cooling system starts operating sooner and has more of a chance of keeping up. If you have room for larger or more cooling fans, that would be good insurance as well. The suggestion to properly seal and duct your cooling air through is a good one as well. I made similar mods to the cooling system of my old VW just to keep it from overheating in the Phoenix heat. I dropped my oil temp about 15-20 degrees in that case. You can use sheet metal, coroplast, high temp foam insulation, and even silicone depending on the size of gap you need to fill.

I would guess that if you do things properly and plan for the worst, you should be able to at least do a partial block without causing any problems. Even the largest fans probably won't pull more air than can pass through a partially blocked intake. But just to be safe if you make the grill block easy to remove, then you can just whip it off if you expect heavy traffic or if your temp starts to climb.