Anyone tried Poster Board or Duct Tape?
 

Well i know people used coroplast but im just wondering if anyone use poster board lol. it might sound stupid but im just curious and for the duct tape...has anyone used it for the grill block? i know my civic bumper can probably get a smooth grille block with just the duct tape over the grille opening has anyone done that or would i need some kind of plastic board?

creativity is great, I actually have choroplast, cardboard, and an industrial air filter blocking my radiator (heat is still below 80 C though GRRR), I would imagine duct tape and poster board would work great, I think there is a red cavalier on here that has made a lot of use of red color matchedish tape.

i ask because black duct tape would match my car perfect i have a black 1995 Honda Civic LX Sedan lol if you look at a honda civic bumper duct tape would make the grille opening delete match it like a front air dam bumper.

the problem is most duct tape uses cheap adhesive and will leave residue or pull paint off if you leave it on for even a few days or in excessive heat/cold. poster board is like paper... water soluble. you'd need to paint/coat it somehow or it'll melt like a newspaper left on the porch in a rainstorm

Yeah, I figured you were just using this for short term experimentation. Duct tape either turns into a gloppy sticky mess, or dries hard and starts delaminating. (I confess though, I duct taped over a rust hole on Marvin to keep spray out of the door until I get good weather to do bodywork, but I'm not worrying about what it pulls off when it comes off, and I'll be sanding off any guck anyway)

silvergt -

Like everyone else said, I would use it to "prove the mod", with a plan to replace it with something more permanent. Keep the duct tape off painted surfaces if at all possible.

CarloSW2

You folks are going to keep blocking radiators and throwing blankets where you shouldn't be putting anything at all until one day you're going to be sitting on the side of a highway with a serious problem, and hopefully it won't be on fire.

Why not just put a higher temp thermostat in and be done with it, or keep choking up that engine and watch one day that crap is going to backfire.

it has nothing to do with increasing heat of the engine. it's reducing airflow to a minimum to maintain engine cooling. most vehicles are capable of not overheating even on 110f day in stop and go traffic. blocking some of the airflow when it's less extreme is obivously feasible and widely practiced on here. If you're gonna be a troll, at least make sure it's relevant as he might well have been talking about wheel fairings.

Aparently you have not visited northern Minnesota / North Dakota, I would say at least 60% of the vehicles here have something covering their radiator openings in the winter. as stated earlier, this much air is only required in the desert with the a/c on going up a hill with the wind. When it is -30F outside, the cold air blowing into the engine bay is enough to keep a small car from ever reaching operating temperatures. I've run these on every car I've owned, and not once have any of them ran hot.

As kamesama said, grill blocks are aero mods which need to be limited to maintain cooling. I think folks with small engines, doing extreme aero, generally find they need only 20-25 sq inches to support cooling. IIRC, basjoos has a 4x6 inch opening, and he wishes he could reduce that sometimes.

On engine temps: A higher temp thermostat doesn't help much if the engine never reaches those temp's. I have almost all of my grill blocked, and the engine was still running ~130*F this winter, well below 'stat temp. I had to block the radiator too, to get the engine up to operating temps.

I'm currently using multiple layers of clear packaging tape for my upper grill block. It works great, IMHO. Of course, I haven't taken it off yet, so I don't know what kind of clean up I might run into.

No one has addressed posterboard yet, also known as foam-core. While a great prototyping material (lightweight, easily cuttable, fairly stiff), it won't last against the elements very well. The outer laminations are paper, and will soak through when exposed to water, unless you seal it (most tapes work fine).

Gaffers tape is preferred over duct tape because it can be removed cleanly. It is more expensive, though.

I used duck tape and cut up laundry box on my Honda for a while. Just to make sure that it didn't overheat in the summer. Once that showned that was going to be no problem, I used fiberglass cloth and resin to finalize radiator block, and painted to match. Cardboard or posterboard won't last long if driven in the rain.

I used cardboard as a radiator block. I spraypainted it and it survived a few rains before I was confident that the car wasn't going to overheat.

Duct tape has some limited uses for car aerodynamics
 

Ever watch the "Red Green" show?

Duct tape is fine for "quick and duty" fixes, but it just doesn't seem to hold up well to heavy use. For example, there is actually a fair amount of air flow (wind) that a grill block needs to withstand, and in general duct tape isn't up to the challenge (at least, not for very long).

Also, as another poster mentioned, the duct tape glue can cause problems for some surfaces, so be careful where you attach duct tape. It's probably OK to tape to plastic panels (as I use duct tape for), but you might affect your paint job (or even trigger some rust) if you tape to the car's metal surface.

However, I have still used duct tape in some situations with success. It doesn't hold up very long as a "grill block" (but will work in a pinch), but in some other situations it has less stress on the tape and will work OK. For example, my CRX has many mini plastic covers on its underbelly. While those plastic covers help smooth the air flow some, they still have many bolt holes and other cracks to catch the wind. So to smooth out the underbelly's air flow, I just put sturdy duct tape on those plastic underbelly panels to fill in (smooth the fair flow over) those remaining holes/cracks. Since I'm taping over the plastic panels anyway (not taping to the car's metal), I'm not exactly concerned about the tape glue hurting any surfaces. And if/when I ever do need to remove a panel (to have work done on the car), I'll simply remove the tape (and put fresh tape on later).

I used Gorilla brand tape on cardboard here in Portland, land of rain, and it held up great, until I took it off to use a modified (stretched out) mesh garbage can, so a little air could get through.

Worked pretty good as a hinge for a "gull-wing" door conversion they did on an old Ford Granada...or was it a Fairmont? Been a long time since I saw that one...

Gaffers tape is expensive, but the cleanup is nil. Always a good thing to have around. I would use that, if you coat the whole posterboard surface with gaffers tape you may get more usage out of it during a rainy period.

Re: Anyone tried Poster Board or Duct Tape?
 

Gorilla brand tape is very tough and lasted on my HUGE protege grill(about 14x30 inches) going 80+ just for example. i never got it wet tho. Blue painters tape is great for testing stuff. it doesnt have much stick but it will last a little while at highway speeds and wont gunkify your paint. Clear packing tape makes a nasty mess when you take it off. just my experience!