Well, if it catches fire that'd help the warmup some!

I can see it helping with fuel economy, but I think there's more risk than it just catching fire from being hot. I'm not exactly sure what but I won't be trying it.

Just throw some fiberglass batting over the engine if you want more insulation.

Aren't your thermostats operational?
I've had t-stats that were stuck open. In those situations restricting the air flow through the rad worked because restricting the coolant flow through the rad wasn't working.

I can see a hot water tank blanket or foil lined fiberglass as an engine blanket to limit the block's surface area from acting to radiate heat, but blocking the air through the rad??? Fix the t-stat!

:eek: I had a GM Service Manager jump all over me for blocking air flow.
Told me something along the lines of; the engineers are pretty good at what they do and that they know their product will be driven in winter and design accordingly and they even test them in all conditions........

Auto manufacturers' engineers are some of the best in the world; those companies have the budget, prestige, pervasiveness, and benefits required to attract them. It can be tough to out-engineer them at home.

However, we have different priorities. Things we do like this are customizing, not necessarily better engineering, just reconfiguring for the way we use our vehicles. They have to build a vehicle that can operate everywhere from the Arctic Circle to Death Valley, whether the driver is a wannabe race car driver, a soccer mom, or a hypermiler. They have to do it on the smallest possible budget and make it look more attractive to the general public than the competition's vehicle looks. There are plenty of other priorities that they have and we don't, but I don't need to list them all...

many on here and other places have said that a good portion of the grill area is for cosmetic reasons.

even the volt has a non-functional grill. they put it on there because that is what the consumer expects a car to look like.

Especially on trucks. A big grille makes it look "tough" Take my truck for example. I calculated that I have nearly 6 square feet of grille area on the front of my truck. The engine is a Chevy small block 350. The same engine that was put in the Caprice and the Roadmaster. The cars with the same engine had a signifigantly smaller grille. If that engine needed that much cooling then the cars would need a grille just as big.

-Jay

Remember that under normal operating conditions that engine works harder in the truck than it does in the cars They don't upgrade the radiator from a dual and triple core in the trucks from the single cores in the cars for nothing. I've got a decently sized grille and if you stand in front of the D when the engine is nice and toasty when it's revved to even 2k your shirt gets sucked to the front. Lugging up a hill for an hour I'm sure the big grille is appreciated by the engine.

Thanks for the interesting discussion. I think I'll go with my radiator 95% blocked for the winter. That will leave a 1 inch gap at the very top of the core. I saw coroplast mentioned. I'm not familiar with this product. Can some one enlighten me?
Also, just as an FYI. I've heard but have yet to substantiate that my trucks radiatior is the same size as what is used with V8 engines. Is there anyone that can provide further info?