G.L.A.R.C.R.C. has it's roots since 1975 and we have always had a successful racing history on nothing but parking lots, the secret is cleanliness.
We use a side discharge leaf blower before we setup the track and it pretty much takes care of small rocks, trash, debris etc. A regular hand held can do the job as well. You can then dilute regular fountain syrup with water or methanol 50/50 and spray it on the area you'll be using. Providing bumps and cracks are minimal, you should have a clean and medium bite surface to have fun on, check out some of our parking lot racing, we run 1/10, 1/8 nitro and G.T., also 1/5 scale.
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www.glarcrc.com