Join Date: Nov 2009
Location: Baker River Valley, NH
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 147 Post(s)
Thanked 146 Times in 128 Posts
That diesel wasn't made from a gasoline motor. I had three of the DX variants that ran for well over 300,000 miles each. I know for a fact that the last one is still in operation in a 1985 C10 pickup at well over 400,000 miles.
The Oldsmobile diesel used a completely different block and head castings. The exhaust manifolds and motor mounts were similar so they didn't have to re-tool the frames. The accessory mounts were diesel only orphans that allowed the alternators and power steering pumps from the Rocket motors to be used on the diesels. The bean counters issued an edict that the diesel had to be assembled using most if not all of the gasoline engine tooling so the engineers obediently removed needed head bolts and downsized them to gasoline engine size bolts as well. Studs did make up for the deficiency but GM never used them.
The fuel filters were a dismal mess as well. No water separation in the box filters even on the AMG Detroit 6.2L engines. Fuel suppliers were not careful to monitor water in the fuel in the 70's... or they purposely watered it down to pad thier profit margins because nobody was watching them. I remember gramps being madder than a wet hen about getting around 100 gallons of water in one 500 gallon shipment of farm fuel. I was careful to buy fuel from the high volume truck stops for my 1978 Rabbit. Local fuel was asking for a frozen filter and rusty injection pump.
The DX variant of the LF9 350 diesel has thick nickel iron cylinder walls and massive crankshaft supports. It can be made into a gasoline stroker that will take serious doses of nitrous with custom Mondello camshaft, cylinder heads, pistons, rods, crankshaft, and extensive machine work.
The 4-6-8 caddy is a similar concept to the AFM systems in use on the LS4 and truck 4.8 & 5.3 without the computing power to make it really work. The EFI ECM system in the 80's Caddy was embryonic at best. TTL logic chips and not much in the way of memory and a real CPU. Most of the early 80's EFI systems were truly awful for that very reason... Anyone remember crossfire fuel injection? VW, Benz, BMW, Datsun, and Toyota all used mechanical fuel injection into the 80's because it worked.
It's quite obnoxious that GM can't get their collective act together and agree on something as simple as the LFX oil filter.
2009 Impala SS
"Speed never killed anyone. Suddenly becoming stationary... that's what gets you." Jeremy Clarkson
Last edited by hatzie; 09-20-2018 at 02:10 PM.