We’re nearing the finale of Road to Improvement season one, and the Big Green 1981 Suburban is currently live on Hemmings Auctions in a no-reserve charity sale to benefit SEMA Cares. If there’s a theme to this arc of our road-trip/build story, it’s pushing limits—in this case, both for the Suburban’s powertrain upgrades and our hosts’ sanity. Check it out in the video above or on our YouTube page (and don’t forget to subscribe, please).
Which brings us to the headline question and upgrading Big Green with new heads, a camshaft, and associated parts. It’s the most involved change to the Road to Improvement Suburban yet. Swapping cylinder heads is far less plug and play than upgrading something like the vehicle’s electronic fuel injection, which we did in an earlier episode. Heads need to be matched to the camshaft timing, the intake and exhaust, and even the desired character of the engine. With that in mind, Mike Musto consulted Tim Torrecarion from Air Flow Research and settled on a setup with plenty of low- and midrange grunt, with the appropriate valve timing courtesy of a Comp Cams camshaft.
It turns out that was the easy step. Installing new heads was an entirely different story. Even in the best scenario, this kind of upgrade involves removing a significant number of engine parts. With a 40-year-old vehicle like Big Green, you’re bound to deal with some stubborn, rust-encrusted pieces that have been in place since Day One, several of which you might as well replace while you’re in there
Thus, you’re left to make multiple trips to the auto-parts store for engine accessories, bolts, clamps, and all the other things that come up in a project of this scope. As co-host Elana Scherr puts it, you’ll want to know where the closest store is, plus your backup store, and a third, and probably a fourth pick as well, just in case. Mike visits all of them and, well, we’ve all been in his shoes, so it’s okay to have laugh at his expense