OK, I was spooked by near freezing temps a few weeks ago and I installed both grill blocks (pipe foam). Yesterday it went up to 30C (about 80F)!! I was on the highway, 100 km/hr. Max coolant temps I saw on the Scangauge were 97C, but it would usually cycle from 95C down to 93C. I think this was the rad fan cycling on and off, probably low speed. Couldn't hear them. This was with the A/C on. Later on (night) I turned off the A/C and the temps went up to 95C from 90 or so. I think the car will turn the fans on earlier with the A/C on. I've seen this on other cars. Anyway, I'm revising my "worry point". I think you can safely run with both grills blocked at ambient temps up to 25C (that's about 75F). Above that I'd recommend not doing it unless you have a Scangauge to monitor the coolant temps. I think the coolant will be in danger of boiling around 120C or so. There should be lots of "head room" before trouble, as the energy dissipated goes up proportionally with the temp diff. - coolant to ambient. Also I don't think the fans were running at max as you can usually hear them when they are running at that speed. Today again it's up near +30C! Our usual max temps for early October are in the 10-15C range. I'm once again becoming a believer in global warming. Oh, and on the highway I was averaging 4.7 l/100 km or about 60 MPG Imperial.
I blocked up about 2 weeks ago myself...we've had a couple days in the low 80s F since then, but for the most part my MG2 and ICE temps have stayed where I'm comfortable with them. Our temps are up and down this time of year, but the benefit is worth leaving them in and they're easy to remove one or two pieces if necessary if temps get higher.
Thanks for the info - I need to read up on the procedure and get some pipe foam. Is there a common place to get it?
I tried to do a grille block on Friday night coming home from work when it was 59 outside, but now its been 90+ during the day so i guess i'll have to wait to do this
I was fully blocked on the bottom almost all summer. Not on the top. It was a relatively mild summer with only seemingly a few days in the 80s and 90s. There were a few days when I removed a strip or two.
Recently it has been cool (60's) in the am and "hot" in the pm. I'd spread my Prius Prayer Towel & kneel in front of the car in the morning blocking off the bottom then kneel in front of the car in the pm removing both bottom pieces when in the high 80's-90. Haven't seen coolant temp above 193F. I thought the Prius runs cold then discovered the Intrigue's coolant is the same temp.
I've been driving with the top 2 grills blocked for the last 2 weeks with temps in the 55 - 70F range. Now that I've a Scangauge I can monitor water temp and still running no more than low 190s F same as w/o grill block. On the weekend I drove >100mile stretch on the HWY and water temps stayed in the low 190s with the top 2 grills blocked. Now that temps are often in the mid 50Fs I notice how quickly the water temps drop back down below 160F in the first 10 minutes soon after you get into a long glide or stop. Tomorrow blocking the bottom grills and hoping to take a run it 60 MPG (US) for life time average.
Any tips to minimize the "look" of the gray pipe foam? I was thinking of wrapping the foam with red duct tape (my Prius is red) and using red tie-wraps.
Look for the softer black foam usually used in A/C installations. Get the 3/4" and cut it lengthways, then fold each of those two in half and wedge them into the slots. You may loose a piece or two, but it looks just fine. Yes, mine is "ugly" compared to doing it the above way, though the gray does match Pearl. The downside to this is you get no salt and rock protection. Mine protects the rads and the chrome grill etc from any road salt (keeps it out) and rocks.
