360 oil pres. Let's hear about it.

[BJSracing]

If you have or have ever had a 360 that had poor oil pressure even after a fresh rebuild lets hear about it and see what fixes everyone has come up with.

[345Dart]

my 360 has 90+ with 5W oil - I have a high volume Melling pump ( and a deep pan). I blended all sharp turns and corners on the inlet and outlet of the pump as well as the interface point between the pump flange and the main cap and blended the entrance in to the main cap.
Don't know whether it helped or not - but it can't hurt. I thought I would have low pressure as my rod side clearance were 23-27th. Bearing clearances were 2-2.5th.
Have you added another 4 holes in the filter adapter for a total of 8 to improve flow?

[BJSracing]

I do not currently have anything. I was just asking of a prob. that I have had and know that has plagued the motor for eternity. most of the problems in the oil sys. on that motor are in the top end of the motor. To be more specific the lifter journals.

[ace26]

the stroker i just got done with has fairly good oil preasure around 65 to 70 when first started once it gets warmed up at 3000rpm on the highway it holds a steady 50 to 55 and after a 30 mile road trip at a idle it holds around 25 or so then right back upto 50ish again ,when hammered it stays around 65 or so.I did the same things to it that 345Dart did and i run 10w30.

[rumblefish360]

They may have forgot the little plug that seperates oil passages that run from the pump to the filter, then from the filter out. The 2 passage ways run parrallel to each other seperated by a little press in plug, shapered like a cup.
Failure to put in this plug will cause low pressure.

[Satty71]

Since you brought it up... ace do you have any problems with your pan going dry with the high volume pump? I am just thinking of future projects and a 360 stroker is what I want to do. A streetable 408 to be exact. I have checked out the stuff sanborn posted and it is awesome, my confusion comes when trying to decide how much of what he has posted pertains to a warm street motor. The engine I have is a 74 360, auto tranny, I have read on here that is the one of the desired years as fae as blocks are concerned. 345 did you enlarge the berring holes and such to increase oil flow? What about mods to increase the oil flow back to the pan? Is there any rule of thumb to make a high volume pump work on the street/strip to be able to wind up tp 6K over and over with no issues?

[dwc43]

Originally Posted by Satty71

Since you brought it up... ace do you have any problems with your pan going dry with the high volume pump? I am just thinking of future projects and a 360 stroker is what I want to do. A streetable 408 to be exact. I have checked out the stuff sanborn posted and it is awesome, my confusion comes when trying to decide how much of what he has posted pertains to a warm street motor. The engine I have is a 74 360, auto tranny, I have read on here that is the one of the desired years as fae as blocks are concerned. 345 did you enlarge the berring holes and such to increase oil flow? What about mods to increase the oil flow back to the pan? Is there any rule of thumb to make a high volume pump work on the street/strip to be able to wind up tp 6K over and over with no issues?

A 74 block is no better than an 84 block. They are both the same inside and out. Only thing you need to do for a good street engine is increase the passages in the block by on drill bit size including the bearing holes. You also need to run the braided line from the RR to the LF on the lifter galley to feed oil to both ends of the crank so the front's don't run dry. If you want to run a high volume pump which is a waste of prower on a street engine, you'll need a large 7 qt. oil pan so it wont run dry. Drain back is not a problem in Mopars with all the large holes they have. On your street engine you'll be better off with a stock pump with a pressure spring from MP added to it.

[Satty71]

DW, where does the braided line go exactly and what size, line fittings? Does this same mod apply to any LA small block or just the 360 blocks? One of the questions I have not being really savvy on the hydro side, would opening the berringings up decrease pressure? Doesn't pressure build when it goes from a larger passeage to a smaller passage? I am pretty electronically smart but haven't ever had experience in the hydo side. My last engine I built grenaded due to poor oiling and running it like I stole it!!!! Please smarten me up. Whats the path the oil takes after it leaves the pump on a small block? Sorry don't mean to be a thread theif!!!

[ace26]

I'm using the milodon low profile pan on mine it's a 72 block,but i have no problems with it at all, just a few simple mods to the system which my brother said needed to be done,i run about 6 1/2 to 7 quarts in it.The mods are preaty much the same as DW and San have said they use but not as intensive but then again my motor doesn't go thru near what there motors go thru either.

[dwc43]

Originally Posted by Satty71

DW, where does the braided line go exactly and what size, line fittings? Does this same mod apply to any LA small block or just the 360 blocks? One of the questions I have not being really savvy on the hydro side, would opening the berringings up decrease pressure? Doesn't pressure build when it goes from a larger passeage to a smaller passage? I am pretty electronically smart but haven't ever had experience in the hydo side. My last engine I built grenaded due to poor oiling and running it like I stole it!!!! Please smarten me up. Whats the path the oil takes after it leaves the pump on a small block? Sorry don't mean to be a thread theif!!!

I'll try to do this from memory. I don't have a book handy or I'd try to get you a pic of it. It goes from the pump to the filter and straight up the back of the block. Hits the lifters and feeds the cam bearings. The whole reason for the line is to feed the crank from the front as well as from the back that way you don't starve the front bearings waiting for pressurized oil. It works on all small blocks and is a must for anything that turns some RPM's. First 318 dirt track engine we built did not have this mod and it turned 6800 for almost the whole season and near the end it came loose. I think it was the 3rd and 4th rods. Best I remember they were purple black looking on the rods due to lack of oil even though everything else looked new. The oil line mod would have prevented this. Go to Sanborns oiling mods thread. HE details with pics how to install it. If you don't have a lot of side clearances and loose rod clearances like in the .0025 or .0028 range you can get away with a stock pump with the MP pressure spring. I've used them in race engines with 20w50 and wide clearances and still got 80 lbs cold and 60 lbs hot. More than enough for a street engine.

[turbododge]

The whole idea of a high volume pump causing the pan pump dry has been hashed here many times. A HIGH VOLUME PUMP WILL NOT PUMP THE PAN DRY ANY FASTER THAN STANDARD PUMP, as long as they are running at the same pressure. The top pressure is set by the relief valve spring in the pump, and the pressure less than that is determined by the resistance to flow of the engine (clearances). In fact, a high pressure pump will put more oil out of the pan because it will push more oil through the same engine resistance.

DWC will argue with this, but just do a google search on it, and you will see lots of info that disproves the "pump it dry" old wives tale. Do your own research before you believe what you hear here.

[BJSracing]

To go with what you are saying Turbo, there is a difference in the 73 to 75 360 blocks even though DW will disagree with that to. They were made off of the 340 casting in those 3 years and had a thicker wall on them. If you don't beleive it well buy a caliper and measure. The #'s don't lie.

[George G. Leverette]

The 360 block you have will take a 60 over bore, the thin wall casting will take a 20 overbore, the exceptions being core shift that produce higher sonic readings on the later blocks. The only place to find the P3690944 opil pump pressure releig spring is at the dealers, the major oil pump manufacturers sell only the high volume oil pump, some equipped with anti caviation devices. Rumblefish 360 has the most probable cause for low oil pressure in a fresh engine. The reasons for the high volume oil pumps is to provide adequate oiling to the lifter bores and top end of the old generation II small blocks, if the lifter bores are bushed a stock pump should be used. Determine the cost of bushing the lifters or purchasing a high volume pump and decide which fit your wallet.

[Fast One]

I've almost finished building a 318 stroker, while checking the lifter set I found there was variation in diameters, also checked the bores & found the same, had to hone the bores to a more consistant measure & polished the lifters, then mixed & matched each individual lifter / bore to the best suited clearance

at first I found some lifters turning ok in the bores & some not, before honing & polishing, an impending lobe wipe disaster I'm sure, also had doubts on oil pressure with over loose clearances in some

also had a friend that built a hi po 360 & had oil pressure probs, turned out to be wrong lifter design, the sales guy provided a dumb bell type lifter saying it was a new style, the smaller base circle of the performance cam dropped the groove a few thou below the oil gallerie & dumped oil pressure