Rode hard, put up wet...and hot

shadoquad

That's an odd question, because it depends on the ambient temperature. If it's 60 degrees or above, gets up to temp with or without a blockoff plate with no issue. If it dips below that, then without the plate it may not get up to temp for a while or at all. With the block plate, it takes about 20 minutes if you drive it cold, maybe more or less if it's 0 degrees or 50. Then if it's wet, it may take longer. If you warm the car up while parked, it'd take just as long as normal, and the temp won't dip afterward.

The block-off plate is extremely easy to make. Just cut a metal plate with the dimensions of the front of the cooler, and use some industrial velcro to slap it on there.

Also depends on where you're going. Residential areas with stops? Warms faster than highway.