Ok, here's some background. I live in southern California and it's the end of the year. This last week we have been experiencing highs of 80 during the day, but the morning temps are in the low 30's...a huge swing. What I would like to know is if it's safe to use lower grill blocking ONLY in the 80 degree temps. Obviously I plan on removing it for the summer when the temps are well into the 100's. I just would like to know, from other's experience, what's a safe upper limit temp to use lower grill blocking. I plan on getting a scanguage at some point, just looking for some input. Thanks
You really need a Scangauge or other instrumentation before you get serious about grill blocking. With your temperate swings and nearby long grades you could be putting bigger cooling loads on your engine than someone driving across Kansas in the Summer.
Yeah, I totally understand the effect that the surrounding area has on cooling systems. I work in Santa Clarita as an ASE Certified Master Tech. I was just wondering what kind of insight others might be able to give me on the subject. ScanGuage is definitely in the future for me since my work scan tool is too big to carry around full time. My daily commute is all of 9 miles with an elevation change of about 300ft. There's not a lot of time to complete the warm-up and stay warmed up with this drive. I'd use a block heater, but I don't have a garage at home, so no electricity. The real bummer is that I have a 5 mile freeway drive immediately after leaving home. Once I get off the freeway it goes into idle stop at the bottom of the off ramp, but is still to cold to stay shut down. That's how I know it's not warming up fast enough. I know I am chasing a minimal gain with the short commute, but I took a 5mpg hit with the cold morning temps and winter blend. If a little bit of grill blocking will help, I'm interested. What I've really been thinking about is building a sort of automatic grill block with shutters that open and close by themselves with temperature. I have the access to actuators and servos at work, I can program ARM architecture chipsets, and my dad is an electrical engineer. This project will be waiting until I have a ScanGuage though.
You can also monitor the temps with an Android phone or tablet and the $5 Torque App and an OBDII Bluetooth Dongle. You automatic grill scheme sounds like a winner.:rockon: I hope you get around to doing it.
A Scanguage or equivalent is recommended, tho since the engine isn't warmed up enuf after the highway run bottom blocking probably wouldn't hurt in the morning. As far as an automatic grill system, that would be cool, but I'd just like to see simple inserts. Top left and right, and a bottom with louvers that one manually clicks open or closed so a set could be in the $100 range!
Block the grill in the morning. Remove the foam when you drive home. Replace the foam the next morning. Lather, rinse, repeat. You can "wedge" the insulating foam in the lower grill without twist ties (you may need to cut some slats to accomodate the vertical bars that support the horizontal bars), but the foam will wedge itself.
I run upper grill blocking in my GenII year around. From what I've seen in the engine bay, any air that gets through the upper grill goes pretty much over the engine/electronics and radiator. I bought a ScanGuage specifically to monitor coolant temps... though I've come to rely on it for lots of other HSD related info for Max FE. Our summers here in Baltimore are typically in the 80's -- with 100% humidity --with occasional excursions into the upper 90's. However, last summer was a hot one with 10 days or so in a row with temps over 100. Your short drive with very modest altitude change is similar in distance and altitude change to my summer commute route. I've run full lower grill blocks up to the mid-60's degF with coolant temps running up to ~195 degF. No problem. You should be aware that the DC-to-DC converter coolant runs though a section of the radiator. On the Gen III, this section is located high and outboard on the driver's side. Once the soft foam grill blocking is jammed firmly in the slots, it is difficult to remove them without tearing at the vertical slits needed to to clear the vertical bars. Rather than putting the foam pieces in and out twice a day, it would be a lot easier and safer until you have a SG to leave a 3 in. by 4 in. hole in the upper three pieces of foam centered about 1 ft inward from the end of grill on the driver's side. Here's a pix of neatly mounted foam frill blocking in a GenII. (Not my car.) The hole for converter coolant is correctly located for a GenII, but somewhat too small. For a GenIII, the small hole shown would be about in the middle of the inboard side of the 3" by 4" hole.
Ffejrobins30: I hope you can put together what you propose and pass on the info. Up here in eastern Ontario, I have full blockage right now but will remove all the lower grille blocking once ambient temps are 10C and above. I have the Scangauge and always monitor temps with it. I have searched for a definitive answer to your initial question about a safe upper limit for temps observed during operation. All I can find is that the thermostat is not designed to be fully open until 93C (199F). On long uphill grades I have seen temps rise to 96C (204.8F) but quickly go back down to 90C (194F). Cheers Mike
