Grille blocking

[jcp123]

I've heard about the aerodynamic benefits to grille blocking, but have some reservations - I thought I'd see what y'all have to say about it. I'm very intrigued by it, though, since the majority of my commute is on rural roads at 50mph, with a 55-60mph stretch thrown in for good measure.

The problem in my car is that the temp is already pretty tightly regulated, and it can get VERY hot down here in Texas. Today, for instance, it got up to 206* just hopping from light to light, and at cruise seems to keep a pretty constant 195-198. Is grille blocking something I just shouldn't even consider in the hot months?

[CO ZX2]

Welcome to GasSavers. Gas mileage for fun and profit.

A large percentage of serious hypermilers here on GasSavers employ either a full or partial grille block. I have a 1999 ZX2 and have my front end blocked completely except the very small openings by the parking lights. There is enough gain to be had to be worth a try.

I have been in Texas numerous times and know how hot it can get there. It is relatively easy to put on some kind of temporary block to see how you do with it. Fix something you can adjust for amount of opening and watch your temp gauge. And that you can easily pull off alongside the road. I actually like to run mine warmer than temps you are seeing. My car shows better efficiency at 210-225 degrees.

[GasSavers_BMac]

Smokey Yunick says the engine is most efficient around 220F I believe but it doesn't leave much room for error and you must have a top notch cooling system.
My Dak has a grill blocker now and in 90F weather it still stays at 198F so I don't think I have any worries. I do have an electric fan. That would be your first saving grace. Just don't block all of the grill if you feel uncomfortable with it. Do a little bit at a time.

[jcp123]

OK, sounds good. I shall proceed with caution, go a little at a time, and watch the temp closely...

[brucepick]

Have a look at lower openings to the radiator & a/c condenser. These days there's usually a large opening below the bumper, often with a deflector if needed to direct oncoming air up to where it's needed.

If you block your grill completely there might still be substantial air flow from below. Just FYI so you know the lay of the land.

[MnFocus]

Hey jcp !

Temporary 'test' grille block w/ a 1"x6" cutout under the ford script attached w/zip ties. Lower bumper grilles wide open as the valance encloses the radiator .
New block is 1/8" lexan just waiting to discover a *pretty* way to attach it .

[thisisntjared]

because of those temp concerns i would recommend installing an belly tray for the car first. then in the cooler months go for the grill block

[jcp123]

Originally Posted by MnFocus

Hey jcp !

Temporary 'test' grille block w/ a 1"x6" cutout under the ford script attached w/zip ties. Lower bumper grilles wide open as the valance encloses the radiator .
New block is 1/8" lexan just waiting to discover a *pretty* way to attach it .

There's what I'm looking for...I imagine that the lower grille opening on my SVT is at least somewhat similar to your newer model. I'm going to go fab one up and put it on after I fill up with the next tank. I'll post results when I fill that tank up...thank you!

[MnFocus]

Keep your eye on that SGII - mine has been running 195-197* with a 202* max on uphills . Keep an ear out for pinging/deto also . Do the top one first - if all goes well block Half of the bottom . All goes well there open the lower valence (in front of air dam ) and try the remainder of the lower grill . I don't want to see an SVT get cooked ,ya know what I mean Vern?

Click on the MnFocus in the lil blue box to the left - you'll see what the 05-07 lower looks like .

[jcp123]

Sounds good. Looks like yours has about the same size total in grille openings, I'll have to see if the cooling parts are in roughly the same place or not.