Carb, distributor, and other top-side bits | Sunbeam Tiger engine swap project - Ep. 10 - Hagerty Media
Folks, we’ve reached a milestone. In the tenth episode of the series, we’re getting the new engine ready to accept fuel and fire, and blow the remains safely out of the back of the car again! Let’s hit the high notes.
FUEL. Eagle-eyed readers will note that the fuel mixer on top of the 289 ain’t exactly a Holley Sniper EFI. What gives? Well, I made the executive decision to use a more old-school Holley product to do the initial engine testing, this 650-cfm four-barrel with vacuum secondaries. It’s the same carburetor Davin ran on the dyno up in Michigan last year, so I know it works and that it’s jetted right for this motor. Why the shortcut? Well, the reality is that I want—okay, need—to know that it will run before I start modifying fuel pumps, adding return lines, and getting into more wiring. To make the carb work, I just plonk it on top, and connect basically the same stuff to it that ran the previous stock two-barrel carb. I’m going to get it running, baseline it, then do the Sniper EFI as part two of this deal. It will actually be pretty fun to do a back-to-back comparison of carb vs. EFI in this car, and now I can.
SPARK. The distributor finally gets installed, and this is a source of angst for me until I hear this motor start correctly for the first time. All the “where do you begin” stuff is ready—the engine is at TDC on cylinder one, balancer is at 12 degrees BTDC, everything is marked so I can advance and retard the spark as needed. The distributor is a pretty sweet piece; it’s an MSD unit that has a high-power ignition module built right into it, and it can handle all the rpm I want to throw at it. It’s got fresh wires, too—what could go wrong? Well, we’ll see …
EXHAUST. Yeah, the old mangy downpipes are still in place from the original exhaust, and I’m reusing them. This is really just a matter of crawling around like a coal miner again on my garage floor and hooking it all up again. Not exciting, but important. I know I’ll get questions (I already have) about why I would take such a sweet, relatively high-performance motor and saddle it with stock exhaust manifolds and pipes. Well, for a couple of reasons—but the biggest one is space. To fit a set of headers on a Tiger takes up more real estate than the original manifolds, and they hang lower under the body as well, producing some clearance issues. Second—okay, it’s a home project, and I’d like to minimize the deviations from a “factory” setup where I can. We’ll see how much power I strangle out of this motor, but I know many people putting good power through stock exhaust systems and they work just fine. As for the pipes, I have a true dual system that is slightly larger in diameter than stock, and it flows through some old-school Cherry Bombs—I think it will be alright!
Enjoy the video and keep rooting for me, will you? It’s about a hundred degrees and humid in my garage as we move farther into summer, and I need to get this thing done so I can survive!