We seem to go through a lot of rubber intercooler boots.  Not sure if it’s a function of higher temperatures from heavy track use, or just normal for a boosted car with a top mounted intercooler. So this time we decided to try to replace them with Silicone boots from Alta which are about a quarter of the cost of stock rubber boots.

The silicone boots are usually sold to people who want to dress up their engine. Given the rat-rod nature of this car, that really isn’t a consideration. We’re looking for function over form.  Do they last longer than stock?  We know installation has a reputation to be much more difficult than the stock ones, but is it worth it? Let’s find out.

My first thought when I opened the box, was, “I could make these….” You just need two pieces of silicone hose cut to 1-5/8 inches wide (40mm), one with an inner diameter of 3.25 inches (80mm) and the other 4.25 (100mm) inches. Now to figure out how to cut them cleanly to size…. (That’s probably why it’s worth just buying them.)

Do the research. You can’t just slide these on like the rubber ones. According to the wisdom of the internet, the preferred method is three-fold: Warm them up to make them more pliable; install them on the intercooler first, using a bent awl to (carefully) pull them on to the horns; and lastly, swear profusely. The process will suck — just embrace the suck. Surprisingly, this was not our experience.

We simmered them for about 10 minutes until they were about 200 degrees F (93 C), dried them off and they slipped right on to the intercooler.  We pressed the smaller end on to the horns first, then wrangled the larger end on, using the awl to ensure it wasn’t caught on the edges. All-in-all it was no more difficult than installing new rubber boots in the past.

The bent awl made it easier, but probably wasn’t required. The top tip we discovered: read (and follow) the instructions.  Next would be to check the edges of your brackets before tightening them.  The stock brackets are reused with the silicone couplers. One half slides into the other and the receiving end has a cut-out on the side to receive the upper half. The edge of that cut-out may be sharp and will cut into the outer surface of the couplers, creating a weak-point that may eventually leak. Also, when you install the stock brackets, be sure to push them out to the edge of the couplers to avoid leaks.