johngeorge Posted October 1, 2012 Share Posted October 1, 2012 Hi all, I was hoping one of you ran into this issue that we are having with our FFR #85 Enduro car. Background: we swapped the stock 302 shortblock (7qt RR front sump canton) for a Boss363ci shortblock, put on trickflow heads, 9qt front sump canton race pan, engine makes great power at the wheels, 385hp/400tq. This past weekend we had our first shakedown at WatkinsGlen, ran Hoosier slicks capable of 1.7+G's in turns, and had oil starvation in high-G turns. On straight running 50psi of oil pressure, then in low-G turns I see oil pressure drop to around 20, but the major issue is long sweeper high-G sustained turns (right hand after buss-stop) for about 6sec oil pressure drops to 5psi! The hydraulic lifters do not like that at all. The other issue which I'm sure is related is we are getting our 2 catch-can breathers full of oil (valve covers to catch can with a -8AN line) but our dipstick is still on and not getting pushed out, i.e. bottom end is vented ok. Thoughts we had: -oil return from valve covers back to oil pan too slow (possible solution is add extra drains back to oil pan from valve covers) -too much oil going to rockers (high volume pump? cannot remember what we put in, thought it was a standard oil pump) -9qt oil pan too big? oil sloshing from pickup? the 302 we ran the smaller canton road race pan and had no issues running the same hoosier slicks Any help would be greatly appreciated. Quote Link to comment Share on other sites More sharing options...
Cobra4B Posted October 1, 2012 Share Posted October 1, 2012 This is a common issue in LSX motors. During sustained left hand turns the oil pools in the passenger side top-end and can't drain back down fast enough. The crank creates windage and throws oil off to the passenger side due to the direction of rotation. This windage and oil being slung onto the passenger side of the pan/block makes it harder for the oil to drain back down. Crank rotation is why it's really only an issue in long left hand sweepers and not right hand. I'm putting a new LS1 crate engine in my father's Panoz and I added Smith Brother's restricted flow pushrods and a good Kevko trap-door road race pan to start. Quote Link to comment Share on other sites More sharing options...
johngeorge Posted October 2, 2012 Author Share Posted October 2, 2012 OK.. did some more research on this topic. It seems we might have 2 possible solutions to fix this: 1. pushrods that have a smaller oil passage (Comp Cams 8310-16 have .050 to restrict flow http://www.jegs.com/i/Comp-Cams/249/8310-16/10002/-1?parentProductId=#moreDetails ) 2. plumb the overflow catchcans back to oilpan Quote Link to comment Share on other sites More sharing options...
Cobra4B Posted October 2, 2012 Share Posted October 2, 2012 OK.. did some more research on this topic. It seems we might have 2 possible solutions to fix this: 1. pushrods that have a smaller oil passage (Comp Cams 8310-16 have .050 to restrict flow http://www.jegs.com/i/Comp-Cams/249/8310-16/10002/-1?parentProductId=#moreDetails ) 2. plumb the overflow catchcans back to oilpan Yep... I had Kevko install an AN-6 fitting on the pan for a return from the catch can as well (port covered w/ the orange cap). The smith brothers pushrods I have are restricted to .040", but I've seen where comp sells some that are .050". Not sure it makes any material difference as both are better than 0.1" which is standard. FYI if you buy restricted flow pushrods (at least with Smith Brothers) only one end is restricted so make sure you install them in the correct orientation with the smaller hole on top. I had 1/2 my rockers re-installed before I realized. Quote Link to comment Share on other sites More sharing options...
Al Watson Posted October 2, 2012 Share Posted October 2, 2012 I had this issue as well on several versions of my 5.0l motor. The issue is in the oil pan and pickup. I developed a simple test to see if a pan/pickup will work. Take said pan, temp mount pickup in its normal location in the sump, fill the pan with proper amount of water, ie 7qts, to sim oil level. Next take the pan and tilt it 45deg fwd, aft, left and right and see if the pickup gets uncovered. Most will. Now 45 deg is for a 1G cornering car, ie 1g down weight and 1g sideforce = 45 angle. higher G turning cars will require more tilt angle. I've found the best setup is the deepest sump, 9", with the pickup centered left to right and slightly fwd of centerline. Cars brake harder than accelerating. beware of street strip type stuff as they put the pickup in the RR corner for drag guys. back in the day when I thought of this I had a 9" drag pan rear sump 5.0L and modded the pickup to be centered and it worked well. since I got a 7" T style moroso pan with center pickup and its not as good as the deeper pan but works. The volume of oil going to the rockers is small so smaller ID pushrods wont help much,drain back on the TFS heads is also decent. If you ask me its all the the pan. Quote Link to comment Share on other sites More sharing options...
johngeorge Posted October 2, 2012 Author Share Posted October 2, 2012 If you notice in the video below, Im dropping oil pressure even under braking! It is a front sump pan, not sure how this is possible.. unless its pumping all of the oil to the upper end so fast, and the oil drains arent big enough for that much of flow (well under braking all oil sloshes to the front of the engine in the valve covers, so only 1 drain instead of 2 front and back.) Quote Link to comment Share on other sites More sharing options...
edhunter Posted October 2, 2012 Share Posted October 2, 2012 John, congrats on the record times up there btw.... FWIW, I've read that restricted pushrods are a bad idea with hydraulic lifters. I run a boss block in my AI car, and have never had any problems with oil pressure. 'Course my AI car doesn't see those kind of g-forces either - perhaps you should go back to the RA1 tire and your oiling problem would go away! . The boss block has improved oiling, so I've never thought I get too much oil up top, as I don't have much in my catch cans after a race weekend. I agree with blown5.0, I think it's a pan issue, I read the cantons don't have the best oil control. I've not looked at a front sump pan very well, but the rear sump "road race" pan doesn't work real well. Might consider adding an accusump for a bit of extra protection. Quote Link to comment Share on other sites More sharing options...
johngeorge Posted October 15, 2012 Author Share Posted October 15, 2012 Ok.. just to update everyone here is what we ended up doing: 1. get/install restricted flow pushrods from Smith Brothers 2. enlarge valve cover breathers from 8AN to 12AN 3. chagne oilpan to Moroso 7qt 4. drain the two oil catch cans back into oil pan Ed Boothman ran the car at Putnam and seemed to be good but still dropped from 50psi to 25psi in one high-G turn (coming onto front straight). We have another test Nov 16th at Thunderhill where we will add 1QT more oil to see if that fixes things. Quote Link to comment Share on other sites More sharing options...
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