6.2 or 6.5?

[94DieselSub]

@ Matuva – No to be contrary to others here, but if this is for a vehicle that has the 3/8” oil cooler lines and a non oil-squirter block I’d advise using a std-vol pump (esp if you use 15W-40). The HV pump was incorporated on the squirter blocks to compensate for the volume loss via the oil jets. On a non-HV application the HV pump will generate additional pressure that in all reality is just wasted energy (IE wasted fuel), and could cause the block located oil-cooler bypass valve to open much more often than with the std-Vol pump.

There is nothing to be gained by using a HV pump on a non-squirter block, other than lost MPG, additional wear & tear of the pump drive sys, and a small additional possibility of oil bypass valve failure do to constant activation. The Oil Pump drive sys includes the Camshaft, with the additional Tq load to the rear helical gear causing additional radial loading & wear of the rear Cam bearings. The 6.5L’s oiling priority is camshaft first, as such, camshaft bearing wear has a profound impact to oil pressure.

 

[matuva]

The data sheet coming with the 6.2l says "oil pressure at idle : 50 PSI"
Should be OK for a non squirter block I think?

 

[94DieselSub]

Everything I said also applies to the 6.2L, the oil flow path is identical. The several inches of water column vacuum regulated by the CDR AKA the tuna can keeps oil leaks at bay by eliminating crankcase positive blowby pressure. The 2-piece rear main seal on the 6.2L is not subject to direct oil pressure, rather it only should have to seal in returning oil & splash oil.

50PSI@ idle is good pressure, and indicative of a new/ish engine! It is also very clear that an HV oil pump wouldn't offer you any advantages! You would be far better off by improving oil heat dissipation & reductions of oil flow restrictions like the leak-prown 4X4 adaptor.

 

[matuva]

OK, I understand that.
Though, I though there is an advantage of getting more volume of oil moved, especially around valve lifters. It is said that 454, 350 engines love high volume (I know, I know, those are gassers :hihi: ) so I was guessing if it is the case for the 6.2 diesel.
I didn't thought about more energy to move the pump, and so worsen MPG

I will be using synthetic Shell Rimula R6 LM (10W-40). Oil change is made every 3-4 kmiles, new oil filter each time.

 

[94DieselSub]

I'd imagine fuel on the Islands is rather spendy, so if you can save a few Gal/Ltr a tank full due to not using a HV pump, I'd say that was a win-win!

I've only owned one 454BBC, but even at 150Kmiles it wasn't having any oil pressure issues with the OE std-vol pump. The only time I'd run a HV pump on a SBC is on a race built unit with loose bearing specs & thin oil. Without a proper built engine with enhanced drainback, HV pumps are known to empty the pan at high RPMs, cause additional crank windage, oil foaming, and up to 20HP lost to the pump.

If you're really anal abou it, you could drop off a new std pump at a machine shop and have them blueprint it! I'd stick with a std OEM unit and sleep well at night! BTW, the lifters contain precision oil metering orifices that limit flow to the top end, and the 6.5L isn't known to eat lifter bores.