Engine and Transmission Tech

Jeremy, According to Dynomation, using my ported Merlin heads, single plane intake,830 cfm 4bbl, 290" would power peak at approx. 7k rpm.,mech. roller cam. We are soo jacking this thread-sorry Phillip. Cheers, roverman.

Was watching this and was just going to let it ride out but.........
A 5 stage pump is waaaay too much for this situation.
Each stage costs you power to run so you only want the minimum needed to accomplish your goal.
I don't know what pump you have but most are modular so just remove the excess modules.
I for one would not multiplex the engine pump for the trans and rear end.
#1 it's not needed
#2 if the sealing between stages is not perfect (which it mostly isn't) you run the risk of cross contaminating the various lubricants.
And #3 Thats a lot of hardware, lines, oil and weight that you don't need to carry around.
Running one stage for the oil cooler also has it's problems. The individual stages when used as pumps are un regulated.
You run the risk of blowing up your oil cooler unless you install a pressure regulator.
Expecting these pumps to control blowby or cause a vaccum in a properly vented engine just ain't gonna happen.
If this were mine I would seriously evaluate whether a dry sump is needed and if it was, limit the pull to the heads and the oil pan. A proper crank scraper and a windage tray will take care of the valley oiling and still give enough oil to keep the cam alive.
All in all remember simpler is better.
The lovely Lynne says thats why she married me.

Cheers
Fred

Fred,

Thanks for chiming in, I post on these forums to get input from guys like you and Art, it is much appreciated.

The only reason I am considering a 5 stage pump is the price I picked this up for, you're right though, I can just get some shorter bolts and turn it into a 3 stage. Would it be worth it to have two pickups in the pan and one in each head? I am planning on oiling through the pushrods so I don't anticipate having the same oil control issues.

I will be running a Kevin Johnson Teflon bladed crank scraper and windage tray. Honestly the main reason for the dry sump is to gain that extra couple of inches of ground clearance so that I can mount my engine lower. I am shooting for an intake runner length of 12.121" (3rd Harmonic with peak power at 6500) and I would like to keep the TBs themselves under the hood, though I expect the trumpets to protrude...

So you're planning on cutting down your crossmember and lowering the steering rack? The engine angle will change so the axle angle should also, and then what of your bellhousing and flywheel? Cut down flywheel, multi disc clutch and custom starter maybe? The oil pump itself doesn't seem to me to be the primary restriction on lowering the engine. I'm like Fred, I like simple. Adding an external pump and an external reservoir is anything but.

JB

This topic was started to help Phillip's oil control problem. Are we any closer to a solution ? To me, it appears his problem, is lost in committee ! I suspect most serious cars in GT2, are running dry sumps. Why, because they need them ! I've listened to all the negatives of dry sump systems, interestingly-enough, Porsche has been using them on production 911's for 40+ years and production Vettes for 6+ years ? I don't believe Porshe or GM use these foolishly. Real racing in SCCA is expensive. If you can't afford it, or are unwilling to shop for "deals", there are many cheaper forms of racing. There are bargins on dry sump components and other serious race parts, on ebay, and other onlines and auto swaps, all the time. Sometimes, you have to dig, if you want bargains-it's own reward. Cheers, roverman.

Art, I just got home from this year's V8 Meet and haven't had a chance to get together with Phillip yet, but as far as I know no progress has been made on the original problem except for some great suggestions here on the forum. I'm not sure that a dry sump would help us much as the problem seems to be a drain back problem to the sump, so wheither wet or dry if the oil doesn't get back to the sump to recycle then we'd still have oil problems. I don't know what Phillip's budget is, but I suspect that he's much like the rest of us and will have to keep things simple for a while yet in terms of cost. All the guys on the team will get together and decide on what direction to move and I'll keep you guys up to date on what's going on when I have news. Thanks for all your suggestions and experience.

Sorry if these drysump questions are getting off topic, but it is a potential oil control solution, so hopefully it is not too far off...

Jim,

I am using a tubular subframe and relocating the steering rack to give myself some more room, I might even explore some alternate steering rack options to move the steering shaft outside of the subframe if necessary.

I'm not sure how familiar you are with the Miata, but it seems like I have a bit more room than you MGB guys. I'm using a d&d fabrications bell housing, the kind that is open at the bottom, so clearance there is fine, we'll cross the flywheel and clutch bridge when I get there, but I have a few options. Actually where I want the motor right now should straighten out the drive-train to be almost level, I don't anticipate many problems with the suspension geometry (no more than what I can expect with a stock car anyway).

I really have the engine where I need it, I'm just trying to regain some ground clearance. My other option I have explored is building an extra wide and shallow oil pan. The C5 vettes seemed to do fairly well with them, but that still leaves us with a few quarts of oil in the heads unless we fix the drainback problem or scavenge oil directly from the heads.

Again, I hope I'm not getting too far off topic, my major question is with the viability of a drysump in fixing this oiling problem?

Update. We have finished the vent line from the fuel pump block off plate area up to the line leading to the catch tank. Used -12 AN line and fittings. Should vent enough pressure from below the cam area to allow oil drainback but we won't know until we can get it on the track. Right now we're shooting for July 15th if we can get the new 8" Ford rear installed by then. Thanks guys for all the help and ideas to cure this problem for us.

Phil and Bill
Looking at these photos and if I understand the problem, it looks like you are trying to create a negative pressure on new tube to fuel pump plate to pull oil to the bottom end of engine. Where does this negative pressure get produced in this system? Hope it takes care of the problem. If not is an engine vacumn pump an option in your class?

I don't mean pull oil through the tube but depressurizing the bottom end for better drainback.

The latter is the idea David. If you go back to the first of this thread you'll find the original problems we had at our first actual race with the oil drainback. I looked at the V8s shown in the British Racecar section and it appeared that we had enough venting on the top of the engine compared to others but we still had drainback problems. IIRC Curtis suggested venting from the timing cover at the fuel pump block off and that's what we decided to try first as it didn't require removing the heads or the oil pan as some of the other solutions did. If this doesn't work then we'll add oil drainback lines to the heads leading directly into the oil pan. We also took care of several other items that caused problems last time out.

I really like the oil pump block off plate, Bill. I could use one of those to help my blow-by issues.

That air filter has got to go, though.

Carl, send me a gasket and I'll make you one minus the AN fitting. Just a chunk of 1/2" aluminum plate I cut out on the band saw and drilled for the fitting.
As for the air filter, that's something we're working on. When Phillip got the restrictor plate made he had to space up the carb about 1/2" so that the butterflys would clear the restrictor, that didn't leave us enough room between the hood and the carb for anything else other than this cut down filter for now. A new hood is coming we hope with a bit more "hump" that will allow for a remote air filter and cool air intake system. For now this keeps the larger stones and birds out of the intake. Bill Davidson trimmed off the choke housing and smoothed out the upper carb areas for better air flow so the filter even though it's low isn't too restrictive.

Hi

I have the same oil drainback problem with my 3port drysumped rally TR7V8. It seems that when I get over 6000 rpm the oil have great diffuculties getting back to the sumppan.
Now the engine is out of the car for service and I have made an oil baffle plate above the camshaft. I have noticed that when engine is running above 2000 rpm the oil is splashing all over, inside the Vee and up into the rocker covers.
Some ford and chevy engines have such an oil baffle plate.
I have also drilled 2 10mm holes behind the timing wheel and into the valley, for faster oil drainback. Unfortunatly this fix properly only works when braking (G-force)
I like the idea of venting via the timing cover, because I think that the venting air is not going to press additional oil up in the direction of the rocker covers. Also crankcase blowby air will maybe enter timing cover via the gap under the front main bearing and into the timing cover venting.

Do you have any photos of the oil baffle for the cam and placement? Just thinking about it wouldn't the valley intake/heads gasket function the same way?

Hi

Picture of oil baffle plate

Per, I would have thought that type of plate would have made the oil drain back problem worse. Stock the only drain back from the heads is via the valley, there are troughs built into the ends of the head specifically for that purpose. I suppose you're running roller lifters as well, I would think that flat tappets would need the oil flow from the valley to keep well lubricated against the cam.

My Huffaker GT1 engine has a syphon line from the dry sump pump, mounted in right rear of lifter valley(4 stage). I would not assume there is more bleed-off from the rocker assemblies than say, the cam and lifters(will vary greatly with cam bearing and lifter clearances). We seem to be rehashing what has been proven in racing circles, for decades. Dry sumps cost some hp. to run. They also save hp. in other ways, like keeping a motor from destroying itself due to oil pressure loss. Blowers cost hp. to run, so why use them ? Good Luck, roverman.

I had the same thought Bill.
The oils only avenue back to the oilpan is now blocked.
This plate will stop the cam from throwing oil up into the valley so maybe at the end of the day it's a wash?
I had an idea while looking at this, feel free to tell me what you think.
What if you designed some sort of scraper for the cam similar to a crank scraper?
This scraper would shed oil from the cam back into the crank case.
This would then turn the cam into a rudimentary pump that would pull oil from the valley back into the sump.
You would need to leave some oil on the cam, but not much in a race engine.
It's just crazy enough to work!
Cheers
Fred

I think the oil that flies up into the lifter valley is coming from the crank. At 7000 rpm the cam is turning 3500 rpm and is much smaller in diameter. It would have to be swimming in oil to throw enough up into the lifter valley to make much of a difference, and as big as the crank is and as fast as it is turning, that is probably correct. If you eliminate enough of the oil coming off the crank it may not be that much of an issue. With the smaller cranks (5L and under) there should be enough room for a deflector or scraper between the crank and cam. Properly designed and located it should be able to deal with the windage.

JB