I just cleaned mine and I used some all purpose cleaner/degreaser on the outside. I took it to a local carwash and sprayed it with the high pressure hose. Some of those bugs were still in there afterwards; so I used a piece of wire to carefully scrape them out. Yeah, I lost some paint too, but I had to paint my intercooler anyways. HTH
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1987 GN 14" K&N, adj. wastegate, adj. FPR, XP Armstrong hotwired, 160*-stat, Hooker 2.5" catback exaust, Thrasher chips, shift kit, trans cooler, vdo boost/oil/temp guages, scanmaster II, Kirban's front/rear frame braces, GNX wanna-be rims, and the rest is stock..except for all the stuff that doesn't last 15yrs.
1987 Cavalier Z24 daily driver. 3-chamber flowmaster and 135db worth of stereo.
Shaun