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Excessive oil consumption

I have worked off lots of small problems since I bought the car about a year ago. Now I’m down to a hard one. It burns oil at the rate of 1 quart per 100 miles.

It had a very rich running Holley 750DP so I couldn’t tell if there was blue smoke in the black smoke. Installed an FITech EFI. It works great. No black smoke. I don’t see any blue smoke on startup or most running (with rear view mirror). Occasionally after well warmed up I see a little on decal/accel.

I have read lots of the forum discussions on similar problems and engine characteristics but I am not sure what, if anything, to do. Of course, I want to start with the easiest potential solution – something that doesn’t involve pulling the engine.

The engine runs great. Very strong. No idle or noise issues. I haven’t done a compression test or removed valve covers. Below is what I know based on invoices I got with the car and ProvaMo.

Engine was rebuilt as 393 stroker. Since rebuild, only has about 4,000 miles, but three owners since rebuild before me.
• Invoices show engine rebuilt in 8/2006 by Richards Machine Shop in Euless, Tx and installed by KG Performance in Frisco, Tx.
• 393 stroker kit (vendor?), bored .030 over, valve job and heads install bronze valve guides, 500 series valves, Comp 284HR roller Cam 32-431-8, new roller lifters and push rods, Comp valve springs 924-16, Comp roller rocker arms 1130-16, roller timing set, oil pump.
• Don’t know if valve guide seals were installed. Did find that a distributer with bronze gears had been installed versus what should have been steel. The bronze teeth were worn to a point, not far from failure.
Don’t know what oil was used before I got it. Oil level was low and dark. I have changed twice using a Mobil 1 filter and Valvoline VR1 Racing oil 10W30 weight. The oil took several hundred miles to start darkening after oil change. It has a high-volume pan. I calibrated the dipstick during oil fills to correlate with level in the pan.
There aren’t any leaks. No oil/dirt/residue seen on valve cover breather or PCV. Valve cover hole internal baffles look clean.
Installed mechanical 0-100 psi oil pressure gauge in passenger compartment. Tube comes from rear of engine off tee with electric gauge sending unit. Cold oil pressure is 70/75psi both idle and above. Even after water temp is up to 175 degrees, idle pressure is still near 70psi. When engine is fully warm, idle drops to 30/35psi and quickly increases with rpm to between 65/70psi.
Installed mechanical vacuum gauge in passenger compartment. Vacuum at idle is 10”-12”. Light cruising shows 18”-20” around town and on highway. Moderate demand and acceleration is 15”-17”. Deceleration goes to 20”-23”.
Gas mileage is 10-12 mpg in mixed driving.

SUGGESTIONS FOR PROCEEDING????? I guess one option is to just add a 2 quarts of oil every 200 miles.
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