Stock oil pump works the best if all your bearings are good.All you need is 10lbs per 1000rpms any more is a waste of hp and hard on the engine parts.A HV pump can rob you of 25hp, and stock bbc pump on a bbc at 7000rpms is about 12hp gone in the oil system.
Final opinions on this setup
- Thread starter patmckinneyracing
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I can understand a HV pump using more power. I don't see more lubrication being hard on engine parts, please elaborate.larryo454 said:
larryo454 said:
you forgot to put how much hp a stock pump takes in a SBC and since I'm running 5w30 Amsoil so that would have to come into the equation figuring out what the M77 takes to tun in my engine..... at 75mph in 5th I'm turning 2000 rpm and if my car was running 20lbs pressure I don't think I'd be very comfortable
When you run a hv pump even with a 7qt pan you run the rick of putting all the oil up top.A hv pump is for a external cooler in front of the rad or remote oil filters on the car or truck.And people ask how come it is hard on engine parts? When you rev the engine and suck the pan dry and put air in the system.You know what air does in the system ask the olds guys when thay rev the olds with out the proper oil system thay beat the bottom end out of the engine.
however, if you have large bearing clearances, a HV pump is a good idea. i had to do that on mine. i had (IIRC) 25? on most of the bearings and nominal was like 15-30? the numbers may be wrong but the ratio is right. anyway, the bearings were showing wear from too little oil after a couple thousand miles. granted, it's a stroker and harder on bearings but not THAT much worse. and if i know pat, he'll be hitting the revs.
so pat, what ARE your bearing clearance?
oh, and an oil cooler is never a bad idea unless you're in alaska or something, especially if you're hard on the motor.
so pat, what ARE your bearing clearance?
oh, and an oil cooler is never a bad idea unless you're in alaska or something, especially if you're hard on the motor.
larryo454 said:
I have no worries of running dry with a BB pump, a BB M77 has 12 teeth per gear versus seven for the small block version, and flows about 10% more oil at the same rpm. Also a HV pump will not empty a 7 quart pan and I like to see some prove of what you claim. If it did I would guess that there would be no one out there wanting to run with one. At higher rpm's the oil pressure dropped on my engine and it was due to needing a windage tray, not that the oil was all up on top. I lowered the volume of oil and for now that cured the problem. You also didn't mention what HP a stock oil pump takes to run it...
Using the formula that I am familiar with to get cfm rating it is too small. 350x6500 (6200 cam max rpm) divided by 3456 you get a rating of just under 660 cfm (628 cfm using 6200 as max rpm)
Does it really matter what the bearing clearances are? If he's going with new pistons, then the rotating assembly needs to be balanced. It's cheap insurance to put a set of new rod and main bearings in the engine as well as some ARP rod bolts seeing as the rods need to be weighed anyways.
I think I'd still stick with the Vortec heads before putting any work into the other heads. They have been proven to work great and if you machine the guide down you can get the extra lift that you want. I'd spend money on a set of Vortecs before perimeter bolt heads just my opinion.
I think I'd still stick with the Vortec heads before putting any work into the other heads. They have been proven to work great and if you machine the guide down you can get the extra lift that you want. I'd spend money on a set of Vortecs before perimeter bolt heads just my opinion.
What I know right now is that the block itself does not need to be bored or honed and the crank in the motor was ground 10/10 back in 2007. The whole motor, top and bottom, is getting rebuilt with new bearings. I haven't pulled the whole motor yet to get a good look at the bottom end. My issue was before the driveshaft snap, the motor was only getting 20 psi oil pressure at highway speeds. I believe that I have the cheap melling pump that is prone to failure which may have been the cause of the oil pressure drop. Melling started the cheaper castings in 2007 which coincides with my engine build and the engine was built on an econo budget.
Mudweizer, I shouldn't be hitting the higher rpms as I was before because I'm going with the 700r4. With the th350 and 3.73 gears before, it was almost impossible to not hit the higher rpms on the highway, which is where I spent most of my time driving the car.
Mudweizer, I shouldn't be hitting the higher rpms as I was before because I'm going with the 700r4. With the th350 and 3.73 gears before, it was almost impossible to not hit the higher rpms on the highway, which is where I spent most of my time driving the car.
you can take a stock crank, put it in a stock block, with stock bearings and still have tight or loose clearance. trust me, tolerance stack sucks! that's why they invented plastigage. it's cheap, simple and effective.
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