Riviera stuff

In typical 3800 fashion my car has begun eating its own intake manifold. The plastic-fantastic plenum that dons the naturally-aspirated 3800s is known to get melted by the EGR system which allows coolant (which flows through the intake manifold for some godforsaken reason) to enter the engine and get combusted. My car has begun eating coolant, and as there is none in the oil and no oil in the coolant, thus ruling out the lower intake manifold gaskets, it must be the plenum. The usual fix would be to buy an aluminum Series III plenum and gaskets to the tune of $160, but for that same price I could buy a Series II L67 supercharged lower intake manifold and a Gen III Eaton M90 supercharger. And the gaskets. The only problem would be the requisite drilling of six holes into the L67 manifold using the L36 (NA) manifold as a guide since the NA engines have injectors in the manifold, and the L67 (SC) engine has them in the heads. For no good reason. Six holes drilled and polished, bolt everything together, wire the supercharger bypass open, and my car would run just how it did before. No change except it would no longer eat coolant. Down the line I could drop another $200 on larger injectors, a new fuel pump (Which I need anyways, as my pump is pretty damn marginal), a belt, colder spark plugs, and a 180 degree thermostat, then another $100 for a license to use my friend’s computer to tune my car and I would make a reliable 270 crank horsepower vs the 205 horsepower this engine makes stock. The tune would also allow me to fiddle with the line pressure settings of my transmission and instruct the worn clutch packs to engage harder, reducing wear and slippage.

All in I’m guessing $600 max to get this done. I’ve priced things out and got a $300 number but this shit always ends up twice as expensive as you’d expect. A 3800 aficionado I’m friends with will be supplying me with parts (injectors and fuel pump, supercharger, etc.) for stupid cheap, so I’m pretty certain I can squeeze in under that goal.

Illustration for article titled Riviera stuff

Engine porn for your time.

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