Question for the Bosswrench

In a 351C in a Pantera, oil routinely heats up quickly to 200-220. Hot oil will drop pressure: cold pressure should be around 70-80 psi at 1000rpms, dropping to 50-60 psi at 190-220 degrees, if the engine is tight. Worn bearings including cam bearings will cause the hot pressure to drop much further and its unhealthy to operate a 351C at high rpms with less than 50psi. Loose oil galley plugs might cause the hot pressure to drop, but they're screw-in allens so thats not likely. If the water temp exceeds 220 at very high speeds in 5th gear, oil temps will routinely go s high as 275 unless you run a full-flow oil cooler. I recommend a 10-qt oil pan, 30-wt oil & a stock (not high-pressure nor hi-volume) oil pump, for all Panteras. Incidently, the stock pressure & temp gauges are highly inaccurate: use mechanical gauges for accuracy & stockers to verify the engine is running.... IMHO, the only oil cooler worth using on a high speed Pantera is a water-to-oil type, unless you don't mind hacking a huge hole in the front end for a decent sized air-to-oil cooler such as Porsches use. I doubt if the lifter bores are undersized, since the likely result would be lifter seizure, not oil heating. Non-roller lifters are designed to spin at maybe 40-50 rpm while the engine is running so you'll normally get a circular wear pattern on the bases from any solid or hydraulic lifters.

thanks for the thoughts. I've ruled out too tight lifter bores. The lifters are probably ok, and show the marks you mentioned. I'm running a standard oil pump, with the high pressure spring. The oil does heat up, but the cooler is not connected yet. Maybe that's all the problem. Aftermarket guages say oil temp up to 220, water at 170, and pressure at idle will bleed down 10-15. Under load at 2500 rpm, the oil P will shoot up to around 40 PSI. I'm hesitant to rev it higher. Bearings all looked good. The block has some Moroso block filler in it. The top 3 inches or so of the cylinder wall is still exposed. Only the bottom inch or 2 has filler. could the filler inhibit the proper transfer of heat out of the oil??

Dan

That much block filler shouldn't affect engine remp at all; most of the cooling is done in the heads. I wouldn't use the high pressure pump spring at all; Two cars had distributor drive gear wear problems from excessive loads with that spring. One car floated its valves below 5000 rpm due solely to excess oil pressure pumping up the hydraulic lifters. Removing the spring allowed revving to 6500! Only slightly advanced (or retarded) timing greatly affects engine temps in Panteras. Mine works best with 6 degrees initial & 34 degrees total (initial+ vacuum+ centrifugal) on today's crappy gas. It runs all day @ 190 degrees water & 200-210 oil temps, up to about 120 mph, then the oil temp starts up. Don't expect much from full-flow air-to-oil coolers unless its the size of the AC condenser. And a bypass cooler that size will only be good for maybe 5-8 degrees lower oil temp.