Grille Blocks in the Summer

[QuickLTD]

I know a lot of us are using grille blocks to clean up the aerodynamics rather than to have the car heat up faster. I am unsure if this is 100% true for for 99LeCouch... I cant speak for him

[99LeCouch]

Mine is both. It fastens outside the grille to divert air from the grille. Also has the side effect of warming up the car a lot faster in the winter.

Currently I'm running with half on to keep the engine from triggering my cooling fans.

[99LeCouch]

To update: With the left half of the grille block pictured earlier in the thread in place, my engine temperatures on a 95-97 degree day at highway speeds peaked at 184*, or just under the temperatures the fans trigger at. So no worries there.

Also set a trip record at 39 miles per gallon over 147 miles. I was up to 39.5 at one point, but several complete stops in the final 7 miles kiboshed the all-time record.

[QuickLTD]

I was thinking maybe you can make a half height block.. Starting from th highest point and ending up mid emblem-ish. That way you still have the 50% of the grille blocked and you are directing a smoth even flow of air over the hood. Awesome MPGs you are getting.

[99LeCouch]

That's an idea that hasn't occurred to me.

Although, how does that differ from blocking one half fully for aero benefit?

[QuickLTD]

I don't know how to explain it. I think you would get a more direct cleaner flow to the radiator. Air slows down as it expands. Trying to fill the right side of the radiator the air will slow a great amount taking that unnatural turn. Symmetry would be a big thing in my uneducated opinion. As far as the aero I am thinking side to side balance and you would split the air better over the hood because of the now equal pressure wave. If anyone has an opinion or a better explanation than me please chime in. I can't figure out how to describe what I mean for some reason.

[winkosmosis]

Blocking the top half makes sense, because that air will be directed over the hood. If you block the bottom half, the flow will just hit the unblocked part and create even more drag. That's why I'll never understand why people do bottom blocks but leave the top grill open. They're doing it backward.

[99LeCouch]

That's a way I can modify my block. I'd need another package of mounting hardware, and a spare minute or two to cut it.

I'd be interested to see what the effects are of having 3/4 of the grille blocked. The car's doing fine in the 90+ degree temperatures with half blocked so far.

[QuickLTD]

What thickness is your material (lexan?) and where did you get it. I might use that for mine instead of the paint it myself plastic I am working with.

[99LeCouch]

It's thin, like 3mm/ 3/32nd inch or so. And it's not true Lexan, but generic polycarbonate (IIRC).

I got it at a hobby shop. Most of the dedicated hobby shops should have a display of the various kinds of polycarbonate sheets you can get. I got some 12"x6" sheets, I think. Shaping was done with a Dremel and a heavy-duty cutoff wheel.