Sbc oil pumps?

[perfconn]

True that 35-40# won't get the job done at 6500rpm but 100# is a bad thing also.High pressure is not necessary but high volume is.The flow of oil through the bearings is what lubricates and cools them.Volume and pressure are two entirely seperate issues.

[hobby28]

Well I hope I didn't screw up. I just bought a 10553 for my new 355 SBC 9:1 hobby stock engine. Clearances .002 rods .0025 on the mains with 10/30 oil.

[Lizardracing]

Perfconn,

Pressure is a measurement of restriction. Increasing the restriction or increasing the volume will both net higher pressure. They are interdependent. Ideally measuring oil flow would be a better indicator of what an engine would need to survive. Enough to cool without unduly wasting power on pumping losses. Unfortunately there's no practical way to measure the needs of oil flow so we instead rely on pressure ahead of the restriction as a reference point.

[TS3g]

The only thing that would make this thread perfect entertainment for us uneducated simpletons would be Dynoman chiming in with some story of how he used an oil pump out of a Maserati or something during a private NASCAR Cup test at Nurburgring with Dale Earnhardt driving and they magically picked up 47hp and 5mph.

[Dirtracer50]

has anyone found a need for higher volume pumps when using the direct lube flat tappets? I installed a new cam and lifters in an engine last season and lost a bunch of oil pressure with the direct lube lifters being the only thing I can think of that may have caused it? Was thinking about installing a different pump this winter to get the oil pressure back to a comfortable range. The oil pressure when hot would never get above about 45 pounds. I pulled the pan and all the bearings look good I would just feel more comfortable with a little more pressure.

[Dirts4Racing]

If you wait till CNC replies you will know exactly what you need. He is the only one that knows everything.

[CNC BLOCKS]

has anyone found a need for higher volume pumps when using the direct lube flat tappets? I installed a new cam and lifters in an engine last season and lost a bunch of oil pressure with the direct lube lifters being the only thing I can think of that may have caused it? Was thinking about installing a different pump this winter to get the oil pressure back to a comfortable range. The oil pressure when hot would never get above about 45 pounds. I pulled the pan and all the bearings look good I would just feel more comfortable with a little more pressure.

Seems like there is a big bleed off some where what was your pressure at idle?

what was the lifter bore clearance with the new lifters?

[Hurst390]

I would check the diameter of the lifters..I don't know about chevy but for my brand it's very hard to find the correct o.d. lifter...
You have to check everything with aftermarket parts..

[ford396]

I would agree with CNC and Hurst390 here. An extra .0005 clearance on 16 lifters adds up to a much larger amount of lubricant bleeding past the lifter. On a positive note, you are putting more oil on the cam lobe. Lifter diameter varies between manufacturers. You may be fortunate that it is a little loose rather than too tight.

Bob

[CNC BLOCKS]

This is a video of oil bleed off between different lifter companies these are roller lifters but it would still apply to a flat tappet lifter as well.

https://www.youtube.com/watch?v=SpfOKr3B3FA

[7uptruckracer]

We had a dart block Mod motor with a 9 quart champ pan the guy put a a high volume pump on and burned it up....He built drag motors not circle track, we turned it 8,500 she burnt up lol We always ran the non high volume stuff We dunno why he changed it but it didn't work for us.....

[7uptruckracer]

I hope this isn't to far off topic I'm not a motor guy what so ever, but have any of you builders run or ran the Accusump system, our guy gave us one but is it really worth it?

[Hurst390]

I'm sure opinions will vary on an accusump...mine is unless it's plumbed in the end of the line...it's nothing more than a pre-luber...meaning if you did empty the canister due to an engine problem/oil delivery issue...unless it's the last thing to receive oil then it's filling that canister and taking volume away from the engine until it is filled..when engine pressure resumes..

[7uptruckracer]

Yeah this one was somehow rigged up on a switch where we could pre lube the motor on startup then it was closed off in cases of low pressure then it would supply extra, It wasn't on the motor that pumped all the oil to the head....but you don't normally have to worry about that in a well built motor.....

[oldgold]

Yeah this one was somehow rigged up on a switch where we could pre lube the motor on startup then it was closed off in cases of low pressure then it would supply extra, It wasn't on the motor that pumped all the oil to the head....but you don't normally have to worry about that in a well built motor.....

my son had one on his figure 8 car so it wouldnt suck air in right hand turns.he had a mechanical valve on it and would turn it on when he started it and shut it before he turned engine off .it heald about 2 qts and he didnt have starvation in the hard right turns.

[oldgold]

We had a dart block Mod motor with a 9 quart champ pan the guy put a a high volume pump on and burned it up....He built drag motors not circle track, we turned it 8,500 she burnt up lol We always ran the non high volume stuff We dunno why he changed it but it didn't work for us.....

so didnt this motor have 80-90 lbs of oil pressure? would it have survived with just a std volumn pump and have enough oil pressure.? i guess i have always been worried about racing my pure stock motor at 6000 with 45 psi oil pressure and zero when pulling off the track after the race.we also run hydraulic lifters and they clatter when the oil pressure is zero to 10 psi after the race.

[dynoman14]

I guess I will go ahead and post as I feel CNC is getting attacked by the peanut gallery that wouldn't know if their line bore and cam tunnel bore was off or not and certainly not have a clue on how to measure it.
I am pretty sure CNC and I have dis-agreed on a couple things in the past but that is the only way to have and intelligent discourse and learn something. I have seen some of his work on an engine rebuild and the block work was accurate and meticulous.

That being said, I don't think a guy has a big head just cause he knows his work is perfect...I am pretty proud that I can build head machines that have consistent valve-job run-out in the .0001" range. Most folks don't know how and don't know where to find the stuff to measure run-out that minimal, so I think it is pretty significant. And yes I have folks out there to prove it as I have listed 10+ of the top Cylinder Head guys in the world that use my Cylinder Head tooling and machines.

As far as the oil pump question goes, I have been HV/HP Melling pumps in almost every wet-sump engine I have built in the last 20 years and have never pumped a pan dry. You don't use them right out of the box as there is a couple hours of cleaning up and blu-printing to do, but after that they are good to 7500 rpm and 650HP capable. I even had a couple mule SB-2 Practice engines I built as wet-sumps just cause folks said it couldn't be done...guess I am just to dumb to know why it would not work as the engines ran at Charlotte, Daytona, Talladega, Nashville & Atlanta with no problems.

I seem to remember back in the 60's they ran on 426 Hemi's, 409 Chevys, and Ford Semi-Hemis and Tunnel Ports.

[7uptruckracer]

Dart tells you to run the block we run with a standard pump. Because it has primary oiling, that's one thing I don't get why do people run the after markets over the GM stuff is it because of this or quality, or cost vs machining cost of a GM? And apparently it did have high OP I wasn't the driver of this one just the setup guy for it. I truly know nothing about motor just find the oiling topic interesting and always trying to learn more, and want to know what I have in the cars i race or work on to make sure the right pieces are there.