Small Block Oiling Mods - Are They Beneficial?

[Rocket]

I will be building a small block stroked for the strip in the new year. It will be a 416 X-block stroker that will likely not see higher than 7200 - 7400 RPM. I was considering performing some modifications to the oiling system to prioritize main and rod bearing oiling as well as improving pumping efficiency. The lifter bores are bushes and I will run a solid roller.

The modifications I was considering consisted of enlarging the oil feed passages in the block from the pump to the oil filter pad and opening slightly the main feeds from the lifter feed passages. I have several articles written about this modification. Is anyone still doing this type of modification? Is it worth the effort to gain the additional oil and improved pumping efficiency? Any other worthwhile modifications?

 

[moper]

What I typically do is much less than others here. There are some posts so I'd say search for "oiling mods". The X block goes a long way to being a more stable foundation and if the lifter bores are bushed you're way ahead of the game. As for what I normally do... I enlarge the feeds to the mains from the cam galley; add extra drainback holes along the valley and deburr the existing holes and openings; smooth the transition from the oil pump to main cap. Because of the rpms you're planing to turn, I'd also add the crossover tube in the valley for the #4 main, and take extra care to make sure the crank finish is perfect and the clearances are dead on. If you can upgrade the oil pump and pickup to anything larger you'll go a long way to keeping it healthy too.

 

[T56MaxTorq]

Pick up the book, "how to build big inch mopar small blocks"

There is an entire chapter on how to improve the stock oiling system. How and why you should do it.

 

[RustyDusty]

What I typically do is much less than others here. There are some posts so I'd say search for "oiling mods". The X block goes a long way to being a more stable foundation and if the lifter bores are bushed you're way ahead of the game. As for what I normally do... I enlarge the feeds to the mains from the cam galley; add extra drainback holes along the valley and deburr the existing holes and openings; smooth the transition from the oil pump to main cap. Because of the rpms you're planing to turn, I'd also add the crossover tube in the valley for the #4 main, and take extra care to make sure the crank finish is perfect and the clearances are dead on. If you can upgrade the oil pump and pickup to anything larger you'll go a long way to keeping it healthy too.

Where do you drill the extra drain back holes in the valley at? Do you have any photos? Also do you use a drill press when enlarging the galleys between the cam and mains?

 

[moper]

It depends on the block. This pic is one I did. I don't run HV oil pumps and IMO, having some extra splash off the crank helps the fast rates of lift I like to run. I also run windage trays so I don't consider the extra windage a big issue. In the pic, the center hole is smoothed and eburred so oil can't puddle, the outer two are tapered at the entry for the same reason. I enlarge the main feeds to 5/16 (slightly larger then size of the hole in the upper bearing shell) with a cordless drill and 12" bit. No press needed, but you need to be careful and clean the shavings out and use oil to make it a nice smooth hole.

 

[RustyDusty]

Looks great Moper. Ya did a good job. At what point do you consider needing a windage tray? I'm not building a race motor, it'll rarely see 5K. I just want to extend the life of my engine, drilling is free, so I figured why not!?

 

[omahamoparguy]

I feel a windage tray could be utilized by anyone who like a little free HP, fuel milage and possibly, less engine wear. All I can say is that the smallblock mopar is NOT the worst engine when it comes to the oiling system. Just a few things sre required to deal with 90% af all driving conditions including the occasional jaunt down the track.
Hey, just go over to the "BUICK" forum and see what those guys have to deal with when it comes to oiling mods. It is just crazy what those guys do to keep those motors together. That book that was posted ealier is a good reference for oiling mods.

 

[RustyDusty]

Hum, I'll have to give a windage tray a shot once I get the money to finish my engine. BUICK is awful man.

 

[Petzschler]

Hum, I'll have to give a windage tray a shot once I get the money to finish my engine. BUICK is awful man.

I'd pass on the tray. If you really feel its nessasary to have some oil control around the crank counter weights, go with a scraper. plus on a stroker, if your gonna use a tray, watch the clearance between the counter weight & the tray.

 

[duster340]

here is my take on a windagetray,factory didnt put it in there for nothing,production enginers dont like adding anything that doesnt make a diference i also look at the windagetray as a part that may help stabilize the bottom end, it may add alitle bit of structural stability in keeping the maincaps togheter efffectively tie them togheter kind of the same as a "modern" maingirdle does but much cheaper and it came stock in these motors

 

[Petzschler]

yah, the engineers used a tray on a stock bottom end. the OP is no longer using a stock bottom end.

 

[rumblefish360]

True, a windage tray is fine for a stock ike set up and OK to a point. When you start turning up the power and inch's via stroking it, a windage tray should be ethier well designed and out of the way or dropped all togther in favor of a deep pan which would move the oil down & out of the way.

 

[moper]

I use windage trays on every smallblock i open the oil pan on. My plow truck has one...lol In terms of small blocks, with the short oil pan rail and wide open oil pans, they need something to simply seperate the crank from the sump. They don't pull oil off the crank really well, that's what a scraper's for. But they keep oil from getting pulled into it from the sides of the crank case and the oil sitting in the sump. I use stock volume oil pumps, factory pans, and lightly modified factory windage trays on everything I do that doesnt need sustained rpms over 5K or peak rpms over 6500. You must run studs to use any tray on the 4" cranks. One of the mods in that case is drilling the mounting holes in the tray to 3/8". Then you can mount it no closer than .100" to the bottoms of the connecting rods. The counterweights are not the closest at any point. The closest part is the rear set of connecting rods when they are close to the pan rails. You also have to tweak the pan by opening the slots to about double what they start at, and the curve is a little tight for the 4" crank so you need to make the radius of the curve in the pan a little larger while maintaining the total width of it. Everything takes about 20 minutes if you take your time.

 

[autoxcuda]

Milodon adjustable windage tray with Milodon stud kit.

Mock up pics below. Some small dings to be close to crank but still clear 4" crank.

 

[66dartman]

The crossover tube to the #4 main, what is the reason? Is there any detailed info on how to do it in a publication? I have seen it on engines that see high rpm, and I have not seen the how & why.

 

[autoxcuda]

Cap matching...

 

[mopardude318]

I'm using the MP windage tray on my stock stroke 318.

 

[moper]

The #4 mod is an older mod. The "how to build a stroker" book by I've seen Szilagyi described it as to help with tappet oiling but he doesn't go into the second part of the mod and that's not what I believe or first learned it was for. He also says use 3/16 brake line and it should be 3/8". The problem is the #3 and #4 main bearings can be starved for oil at high rpm if the oil speed thru the right side galley is too fast due to larger clearances and higher oil volume. This happens even if the lifter bores are bushed or the galley tubed. Oil simply doesnt turn well. It was first devised by Larry Atherton and Mullen and Co. and will work to rpms beyond the ability of any parts available (10K). I first read about it in an older (intially written in the 70s) mopar building book as part of a trans am build up for extended high rpm operation. The important part is the angle of the fittings where they tap into the gallies. There are write ups on it in a bunch of places. Just make sure the angles are exactly the same on both ends for that step. The part Szilagyi misses aside from only saying to use tubing that is way smaller in delivery volume than the holes in the block is the blocking of the crossover for the left side lifter galley at the front of the right hand galley. That means the oil goes into the RH galley feeds #2, #3, #4, then it goes to the tube which is placed behind the oil passage to the head behind the #4 cam bearing bore, accross the valley, and hits the LH galley just in front of the LH passsage to the heads in front of the #2 cam bearing bore. Then down to the #1 main. #5 is fed on it's own. This mod reduces the oil to the tappets too but your bushings did that anyway.

 

[Rocket]

Thanks for the replies. I will pick up the big inch small block book. As for crank scrapers does anyone have any pictures or sources for one to start with (likely a few mods to make it fit)?

For oil to the heads I know some builders also groove the cam journals or bearings on #2 & #4 and restrict the oil to the heads with screw in restricters like carb jets. While the Mopar engine book says never to restrict the oil to the heads I can see the logic in maintaining constant oil flow to the heads via the grooving vs. Waiting for the holes in the cam to align on every rotation. Any suggestions on the oiling to the heads?

 

[66dartman]

Thanks moper for the explanation. I don't think my 6000 rpm 408 should need it, but it's good to know for future 318 based high rpm builds I plan.

 

[moper]

I try not to increase top end oiling, but I do make damn sure what's there is working 100%. Many cam bearings do not align perfectly with the holes in the block. So I taper the backside of the #2 and #4 cam bearings so there is less of an interruption where the oil passage would intersect with the bearing hole. I suppose this also means the holes are expoased a little bit more. I know I have never had an issue with rockers being starved. The trick is really to get "just enough" oil up top, because the lower end REALLY needs it. That's why they get restricted. When things are working, there's already more than you need for most builds.