Catalytic converters
OK, cats on our older cars for cleaner exhaust… gotcha.
I haven’t used one on a upgraded engine with a cam. Just on my ‘79 Magnum with exhaust manifolds on a stock 2bbl. engine with the only mods being a swap to a 4bbl. Carter 625 and a MP ignition box since the Leanburn did its normal thing and failed.
The exhaust was 2-1/4 with an H pipe, then twin cats. Exhaust exited at the bumper. It did very well on the test.