Does anyone know the gallons per minute (gpm) flow rate of the 308 engine? Thx
Try a search on "Accusump" and read those 182 threads -- seriously, there may some prior information there.
My foggy recollection (so don't trust it ) is, in some of the discussion about Accusump, the 308 oil flow rate was mentioned as being about 1 quart/sec at high RPM (so the argument was the 3 quart volume available from the Accusump wasn't enough for a high g turn lasting longer than 3 seconds). What are you trying to do that you need to know this flow rate?
Looking to add a pre-oiler pump to a 308. Just trying to find out what the flow rate would be at idle to establish a baseline.
What are you trying to prevent? In over 40 years not a single Ferrari V8 (prior to the 360) of the many I have rebuilt was done because the lubricated parts were worn out. Prevention of wear of bearings, cams, crank etc is totally unnecessary. In many cases during overhaul the original parts could be easily reused and often are. Now if you could make pistons, rings, liners, valves and guides last longer it may be of use.
Getting in to an online debate over the answer to a simple question, while having to explain or justify what I am doing.
Any typical engine pre-oiler would be OK if you just want some pressure/lubrication prior to engaging the starter. In this case the actual flow rate isn't really important, you just need to generate 10-15 PSI of pressure to "charge" the system before the oil pump itself takes over. You can even set it up on a timer to "charge the system" periodically if the car isn't running for an extended period. Have it run for a minute or two every so often.
Pre oil systems are generally only fitted to big diesel engines, small cat genys dont have it. You could add some STP oil treatment to the sump oil to protect the first start. My old mondial ran with it for15 years- when it goes cold it is very sticky so protects the bearing surfaces at the initial start until the oil pump catches up. Never did mine any harm anyway
A couple yrs ago I did a bunch of calcs for a dry sump conversion project. Dug into the files... These are calculated flow rates for the oil pump. Rpm/GPM 1000/0.76 1500/4.55 2000/8.35 2500/12.14 3000/15.93 5000/31.10 7000/46.28 8000/53.86 8500/57.66
Approaching a gallon a second as the engine closes in on red line? I wonder what percentage of that goes out the pressure relief valve. I'm guessing way over half, but I have no real idea.
Oh yeah, that's just the flow rate of the pump. I forget the rho offhand in the calc, but should be for the std oil at operating temp. I've got pumping hp calcs as well for maintaining pressure.. at full tilt it's something like 1.2hp to just turn the gears to supply 60psi.
Yes, as noted, the flow would be limited by the relief valve. So at whatever RPM the relief valve lifts, that will be the maximum oil flow. For example, on my 328 at operating temp running Mobil 1 0W40, the oil pressure gauge reaches a bit over an INDICATED 85 PSI at around 4000 RPM where the relief valve lifts and, of course, the pressure (and the corresponding flow) never goes higher. At a cold start, the pressure hits the 85+ PSI (relief valve lifts) at 2000 RPM fast idle! BUT it is important to remember that it is oil PRESSURE that is the critical thing to know. If you have sufficient oil pressure - generally considered to be 10PSI per 1000 RPM - you automatically have sufficient oil flow. For pre-oiling, you are just pressurizing the system sufficiently to push some oil into all the bearings/passages to ensure there is oil present and under pressure the instant the starter is engaged. There is no need for any great amount of pressure for preoiling; if the oil passages/galleries are 'full', the instant the motor starts spinning, the oil pump is providing pressure throughout the system.
