Making a Fiberglass Air Scoop

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Intro: Making a Fiberglass Air Scoop

it all started when I noticed my buggy engine would run a little hot on the highway so I came up with an idea to make a scoop to help force cool air into the cooling shroud.
the only reason could come up with as to why it only happened when I was driving was because it was being blocked, kind of like flying your hand out the window it catches air and wants to lift but if you put it behind a car door mirror it falls in the stale air

STEP 1: So I Wanted Something to Catch the Air and Direct It Into the Engine Cooling Fan

first up was cutting, gluing and carving foam. ts messy and all the static generated makes the shavings stick to you and everything else. after you get the shape that you like then you sand it to the final shape

STEP 2: After Sanding and Smoothing As Best As Possible in Order to Fiberglass Over the Foam You Need to Cover It in Foil

the reason for the foil is to protect the foam from the fiberglass resin. because it will dissolve the foam without foil as protection

STEP 3: After Its Completely Covered in Foil You Fiberglass the Whole Outside

once it has a few layers of fiberglass let it completely cure then cut the fiberglass mold in sections and remove the foam

after it is all removed put all the pieces back together and fiberglass all the seams back together and let it cure

next is a lot of sanding and smoothing then primer and painting. then you have the finished product



Note:. wear protective equipment when handling fiberglass or cutting fiberglass

STEP 4: Installed

once installed I did a series of temperature test at idle and while driving. the air scoop did the trick it went from 240°F - 250°F. down to 200°F -210°F on a hot summer day. I also installed an oil cooler and fan later on and it brought it down to 180°F 190°F.

I'd like to add that the engine has all of its cooling tins and has no leaves or mud or debris blocking the fins... its a 1776 turbocharged engine with flat top mahle pistons and cylinders 7.4:1 compression and 7 lbs boost. as well as turbo cam with straight cut gears, 8 dowel crank and h beam con-rods. it makes around 190 HP and the 0 to 60 time is 4.1 seconds. the whole thing weighs 1,114 lbs. it might be faster but I'm afraid of destroying a 3rd transmission. so I feather the petal so it doesn't give a sudden jolt from a dead stop basically I don't dump the clutch and I limit the engine revs at or under 5,000 rpm

7 Comments

That looks sweet. Very professional looking. I think you need to look at your timing and A/F ratio. that engine should not get that hot with that weight. My 10:1 2276cc engine with dual 48s never went over 205f on a 7 day 2500 mile trip. Stock cooling tons and no external oil cooler. Also, you should run your oil around 215f so that water will boil off and prevent sludge, this will also extend engine life. Again, really like the idea and would build one if I had a buggy.
I have a 1776 with 7.4:1 which is turbocharged the distributer is locked out at 24 degrees advanced so that could be why I had a heat problem
The foam will not melt if you use epoxy resin rather than polyester resin. Also, you can use denatured alcohol to thin and clean up epoxy resin.

Epoxy resin is usually notably more expensive than polyester .

that is true. the foil did help as a barrier so nothing stuck to the foam also it helped release from the mold... I already had fiberglass resin. and didn't want to make an extra trip. but you are right epoxy resin does not eat foam
Dude! That's a freakin cool buggy!! Also, sweet air shroud!
sweet....