Joe12459
Well-Known Member
My son's 81 Mirada was an original slant six car, but the previous owner somewhere along the line replaced the factory engine with a mid-sixties 170 slant six. The casting number, 2463230-2 seems to indicate post '64 production. The stamping, EW170R 2869 0075 is a little more obscure. The W might indicate a warranty block, and the E might indicate 1967 production year, but that's not my question. This engine runs very well, with an initial timing of 24 degrees BTDC and total mechanical advance of around 40 degrees at 3500 RPM. That seems like a lot of initial advance to me, but it runs/idles great. No ping/knock/detonation at any RPM/load. The engine has a '77 or so super six manifold, new BBD carb, and new electronic ignition with vacuum advance. Compression check shows 125 +- 2 PSI in all six cylinders. When I changed the timing chain, everything appeared factory, including the Teflon gear that came off in good shape, so I didn't degree the cam. I guess this is more just curiosity than anything, as the engine performs well. I'm just curious if anyone else runs these engines with that much initial advance. If anyone has more info about the engine numbers, that would be great, too!