Quoting: Andy
Still prefer the sound of a V8 with a nice cam in it to a straight 4 pot ragging it balls off!
That's why you want the latest Northstar VVT V8 engines, continuously variable timing on both intake and exhaust valves.
High tech does not have to be Japanese or European:
(I found this when looking for the valve timing info, learnt a bit more about my engine in the process!)
The "Northstar" V8, as it was then known, was an evolution of the Lotus-designed Chevrolet LT5 all-aluminum DOHC 32-valve V8 used in the Corvette ZR-1. Archrival Ford Motor Company was developing a similar engine at that time as well, and Ford's Modular engine would precede the Northstar into production with its introduction on the 1991 Lincoln Town Car. Both continue in production at 4.6 L of displacement.
Capable of producing 300 hp (224 kW), the Northstar featured a cast aluminum 90° V8 block with 102 mm (4 in) bore spacing split into unitary upper and lower halves. The lower crankcase assembly supported the crankshaft without conventional main bearing caps. An oil manifold plate with an integrated silicon gasket forms the oil gallery under this. A typical oil change used 7.5-8 quarts of oil.
Cast-iron cylinder liners were specified and the forged aluminum pistons included valve clearance, making Northstar a non-interference engine, with bronze pin bushings and free-floating piston pins used.
Cast aluminum cylinder heads were used featuring 4 valves per cylinder. The heads used dual overhead cams which are driven through the "maintenance-free" cam-drive chain case. The cams act directly on hydraulic lifters on the ends of the valves and are fed with a lubrication passage drilled through the cylinder head lengthwise. The intake valves are inclined at 25°, while the exhaust valves are canted to 7° with center-mounted platinum-tipped spark plugs. The cam covers were fabricated from magnesium for light weight.
Eight thermoplastic tubes were used in the induction system, leading to sequential fuel injection. The engine uses a direct ignition system with a single coil per cylinder and no distributor. The PCM controls spark and fuel injection timing as well as the shift points for the new 4T80-E transmission.
One notable feature, advertised at the time, was the fail-safe cooling mode which allowed the engine to continue running for a limited time without any coolant at all. It alternated banks of cylinders, basically "air cooling" the inside of the cylinders, to maintain cool temperatures, allowing a Northstar-equipped car to be driven with no coolant for about 100 mi (161 km) with no damage.
Another unusual feature of some Northstar-equipped cars is a liquid-cooled alternator used on Cadillac's Seville, DeVille, and Eldorado. The liquid-cooling helped prolong the life of the alternator in these electronic-laden models, though GM reverted to a traditional air-cooled setup for 2001 to eliminate potential leak points and extraneous tubing.
Later developments included variable valve timing, which can vary intake by up to 40° and the exhaust by up to 50°. This system was devised for the longitudinal LH2 version, and has not, to date, been used on the transverse front wheel drive engines due to packaging considerations.
