Engine and Transmission Tech

Hi Bill,

I'm with Art.
Putting a fitting into the valley cover will be a problem.
It can't support any weight or vibration and it's a problem when you need to change gaskets.
As well you'd be draining oil right into the area thats giving you the problem and venting an area that the valve cover vents service adequately now.
The oil return needs to be below the valley opening along with the new vent.
If your using anything smaller than a -10 line for the drain, then it needs to terminate in the pan below the oil level. Or it will push oil back up into the tank. A bigger hose will let the air pass by without taking the oil with it so it can go anywhere. Such as the fuel pump flange.

Cheers
Fred

Using the fuel pump cover as a vent/drain might be helpful, but I suspect the 4 corner drains to the pan are going to work out the best. Are you using a baffled/trapped oil pan and scraper? That car undoubtedly generates enough G's to slosh the oil up around the crank where it'll promptly get thrown everywhere except where you want it. Under those conditions even the best drain back system may not be enough. If you use the 4 corner system you can also baffle the rocker box to direct the oil down the drains. I'd put the drains in the heads themselves since the outer flange rises up to meet the valve cover. You could also put baffles in the lifter valley to keep oil from being thrown up into the rocker boxes. Lay one over on it's sides and you'll see where you need them.

JB

Thanks guys. I'll pass the information on to the rest of the crew. As for me, enought to do for my own car to get ready for the trip to Townsend so I'll have to let the race car wait until I get back.

Many modern V8's, like Lexus, Gen III hemi,etc, have 4+ large drain-back ports cast into the block, that dump inside the pan rails. The latest winner of Engine Masters(Gen III hemi), extended these ports downward with extension tubes.Cheers, roverman.

Under the rocker stantions in the head, you will see an oil galley front and rear. Only one is used per side as the heads are reversible. I bushed all four just so I wouldn't have to remember which head for which side. I had my machinist tap the oil hole and thread in a brass plug with a hole drilled into it. It will be loose, but not to worry, the stantions hold it in place so it won't back out. The oiling hole is about 190 thousandths originally. First I tried reducing it to around 90. Still too much oil pouring into the valve covers. Next I tried drilling .055 holes in the bushings. That seemed to do the trick. Oil is now manageable. Originally there was so much oil it couldn't drain back to the pan fast enough. The blow by from the bottom end was forcing the oil up and out of the breather at higher RPMs. Remember this was with shaft mounted roller rockers, and we also had one of the oiling holes in the rollers welded shut. Too much trouble in my opinion. Next time were going to use plate mounted rollers. A buddy of mine had the same problem and he plugged the hole in the head completely and is oiling up thru chevy hollow pushrods. Seems to be working as well, but not a lot of miles on that engine yet.

With roller rockers, pushrod oiling is a pretty good option, provided the rockers are designed to channel splash oil into the needle bearings. If they are not, a depression of some sort in the top and a hole draining into the bearing area should do the trick.

When using bushed rockers the amount of oil delivered depends on bushing clearances so obviously tight clearances mean better oil control. But, I've seen worn out engines that did just fine because the bushings had worn on the bottoms to the shape of the shaft, which had also worn, leaving as much as a 1/16" gap at the top. This still worked because the oil feed holes were at the bottom and spring and lifter tension kept the bushing pressed against the shaft, mostly blocking off the feed hole. Odd as it sounds, something like this can actually leak less oil than a brand new shaft and rockers. But it'd be less than ideal for a high speed motor because of the change in geometry from wear.

Restriction of rocker shaft oiling has in the past been a very common method used to keep oil in the bottom end. Early on it was recognized that oiling at high speeds was markedly more than what was needed and that there were benefits to restricting the flow. The usual method was as Todd described for his roller rockers, but it should be understood that the risk of this method is poor distribution from front to rear. Of course on a road coarse this may not be a problem.

Pushrod oiling also has been used successfully with shaft mounted rockers of the more conventional type, but often this was done by using pressed steel unbushed rockers where the rocker itself forms an oil reservoir that collects splash oil from the pushrod. You see these in the 350 SBB for instance, and it is a system that works very well. You might be able to adapt 350 rocker shafts to your engine, although the spacing would need to change some. The center pushrods on the 350 are moved over about 3/8" and the intermediate ones a bit less. The outer ones are unchanged. So it may be possible to juggle things around enough to match up properly. The stands should block off the oiling ports in the heads, and then hollow pushrods and correct lifters to finish the job. May not make a lot of sense on the test motor though.

JB

"Maybe" we should ask the guy who built the motor, for his solution ? I'm going to risk some more objecture here ,and go on record to say, needle roller rockers are best suited for a mech. roller cammed, 3.5L Rover, to be a serious contender in GT 2. My Huffaker GT1 car used Volvo adjustables,(I think they were allowed at the time), non roller, and while strong, they produced a LOT of scrub on the valve tips ! These would run up to 8k rpm., but at the price of quick wearing valve tips.Requred changing "chain" after every race ! Of course now,I would use a gear or belt drive, on the cam. Good Luck, roverman.



Edited 1 time(s). Last edit at 05/05/2011 12:28PM by roverman.

Art
What gear drive is availible?

Art, Bill Davidson built the engine and it's basically a stock Rover long block at this point. It was just a budget piece to get the car on the track so we could sort out the chassis without putting hours on a real "race" type motor. We'll keep this mule engine in the car for this year I suspect and finish all the sorting of problems such as the oil problem we're addressing now as well as some handling issues Jessie reported, then we'll build a more highly modified engine for the car. That engine will require a lot more thought and engineering. As Phillip reported in another thread we have to run a restrictor plate under the carb and that will have a lot to do with determining just how much cam and head work we should run. Having the intake valves open longer won't help much if you can't fill the cylinders because of the restrictor plate. Finding the right combination in that area will take some tiral and error I suspect and we don't have the resources like the big boys in NASCAR do to try different combinations for their restrictor plate motors.

Milodon did make them,(Buick V6 with odd-fire nose). I had (2) roller cam blanks made with (3) bolt mounting, to use sbc belt or gear. Cam/crank centerlines are closer on B.O.P.'s, idler bar will need a mod. Cheers, roverman.

Quote:

You will need some sort of deflector or baffle at the fuel pump flange as the timing chain will be firing oil right at it.

Maybe. Not sure there is much oil in that area. One of the mods I see in all the books is to drill holes in the block to better oil the timing chain.

Jim Blackwood suggested this mod for my badly blowing 215 last Summer. By coming out, then up with the hose any oil should drain back. Or, run it to the catch can, then back to the oil pan (as mentioned).

Not having run a Rover on a dyno with a "clear" valley cover, I suspect oil is actually try to fling/levitate up/out of the valley drain slots. Why?, crankcase pressure and throw-off from the cam, lifters and rotating assembly.Of course this impedes drainback from everything, above this area. I like the idea of welding/closing these slots,(stronger), and draining valley at each end, yes,rear would need a port added. IMHO, roverman.



Edited 1 time(s). Last edit at 05/11/2011 04:55PM by roverman.

So where would be the ideal places to scavenge oil from on these motors, specifically the 4.0l varient?

I ask this having just picked up a 5 stage oil pump. My plan was to run two pickups in the pan, and one on either side of the lifter valley, but maybe I should be pulling from the heads instead? Maybe just one pickup in the valley and 3 in the pan, bye bye crankcase pressure...

Jeremy, road course or oval ? For my build, I would seal-up the lifter valley and use one scavenge in it. 5 stages is a lot for a Rover. I would limit bleed-off from rockers. My Huffaker GT1 motor has 2 in the pan. I suspect a clear valley cover, on engine dyno, will tell you where, IMHO.Good Luck, roverman.

Road course, and street driven for that matter. 5 stages is a lot, I was looking for a 3 stage but found this one for $300, practically new. I'm thinking about doing Chevy stud mounted rockers, but either way I was planning on oiling through the pushrods, that should limit oil to the valve covers.

I wish the clear valley cover wasn't so hard to do on these motors, on the LS1 it couldn't be easier, has anyone fabbed up a valley cover independent of the intake gasket? I was thinking of doing one out of UHMW polyethylene, but I guess I could use acrylic or similar for a few dyno runs. R&D budget is small for this project, might end up doing the dry sump and find out later if I need to change the scavenge pickups.

Just a thought
Didn't Group 44 racing have to resolve this problem when they raced TR8s......If any of their alum is on maybe they could comment. What oil pan should I put on my street/auto cross V8 B?

Jeremy, I would try .06" polycarbonate,(Lexan). "temporary" on engine test stand-only ! Possible to use extra stages for trans or rear end ? Modify pump to "remove' un-needed stages ? David, I would get pic's of "Phillips" wet sump pan in his RV8 GT 2 .car. A crank scraper is a good addidion to any motor. I would also use 1/more, Moroso 1.5qt., verticle "bottle" accumulator. Street and Slalom is is easier for oil control. The duration and severity of lateral G's is less. IMHO, roverman.



Edited 3 time(s). Last edit at 05/19/2011 12:37PM by roverman.

I will give the Lexan a try. Using one stage to pump trans fluid through a cooler is a good idea, otherwise I am thinking I will be using 3 stages on the pan and one in the lifter valley. I'm not sure of you can have a problem with too much crankcase vacuum? Am I going to suck my combustion gases into the pan?

Kevin Johnson makes a crank scraper for our motors for a good price, including a zero clearance teflon scraper.

Jeremy, each stage produces vacum and pressure, so I think it could "dry sump" the trans, pump through a cooler and into "spray bars", like Bonneville racers use ?
Most modern manual transmissions don't need much over 30 wt. for racing, your results may vary. I think I might "slow" the pump down, to where it produces just enough psi at lower rpm. If your gaskets impload(lol),OR your getting inlet charge into the crankcase, I would check with a "blowby" gage. IMHO, roverman.

Yes the idea will be to size the sprockets to produce the minimum hot idle pressure. Peak power on this motor will likely be at 6000rpm, so at least I don't have to worry about dealing with an 8k+ rpm range. I could always route one stage back into the pan, that should cancel out...

I'm not sure if I want to pull apart a T-5 to add spray bars, seems like overkill, but then so is a 5 stage oil pump on a rover...or ITBs for that matter. Lol

Checking for blow-by will be a must, I'm going to be upset if I'm not making at least 300hp with this hunk of junk...