I usually race a 914 race car, but it's engine expired at the end of 2019, and the rebuild is still in process. Many custom parts, suppliers on reduced capacity due to COVID, etc....

In the mean time, I started autocrossing my street 914, a solid, but unrestored '74 LE.

I had so much fun with that for the 2020 season, I decided to try it out at a DE track event in March. Everything was great, having a ball at Thunderhill , until a rod bearing spun during the 5th run session late in the day. D'oh

So now I have yet another engine to build before I get back to my race motor project. I plan to keep the rebuild mostly stock, but looking for suggestions to help make the new motor more reliable for DE track use. I finally have all the custom parts in hand for my race motor rebuild and I'm planning on getting that finished up in the next 2-3 months. So my street car probably won't get pressed into track use again soon, but you never know, so why not build something that can withstand some track usage.

The previous motor was just what was in the car when I bought it 25 years ago from a local Porsche mechanic. He got it from a client that couldn't pay for some repairs and ended up giving the mechanic the car. But that's all I know of it's history before me, so the pedigree of the motor was completely unknown. Because of that, I always considered the motor sacrificial. I figured I'd run it until it blows up and then build something proper. It took 25 years, but that's where we are now.

The motor was a bone-stock D-jet 2.0L. At the track it was running very hot, just under the red zone on the stock oil temp gauge. Air temp was 75. When the bearing spun and the loud noises started, I looked down at the temp gauge and it was solidly in the middle of the red. So more oil cooling is obviously top of the list.

I never noticed the oil pressure light coming on, so I don't think I was oil starving it, but I wasn't making a point of specifically checking it and the stock light is small and often blocked from view by my hands and the steering wheel, so I couldn't swear that it actually never came on.

While the car is a solid driver now, since it is an LE, I'd like to restore it to show car condition eventually. For that reason, I'll keep the rebuild as a D-jet with a stock external appearance. But I'm open to non-stock internal parts, and any new external systems (like oil coolers, deep sumps, etc.) that are easily reversible.

So those of you with some track experience with fairly stock motors, what would you suggest for both rebuild parts and additional systems that will allow a stock D-jet to stand up to DE track use?

Thanks,

Andrew Blyholder

A Tuna can and a front oil cooler

I’m sure you were loosing oil pressure in the corners if the motor did not have a tuna can on it when it died

They loose oil pick up in the corners

Almost guaranteed this is what caused the spun bearing. Lack of oil pressure

You think a tuna can is enough? Full 1.5 qt. deep sump not necessary?

Andrew

I've been thinking to go with a Webcam 73 grind cam and the 96mm pistons. So that's both a slightly longer duration, better breathing cam with a slight increase in displacement. Wondering if that will still all work well with the stock D-jet. Anyone out there done that specific combination?

Andrew

I've got a couple of deep sumps I'm about to put in the classifieds...

My 2L Historics car was raced in Improved Touring A then I.T. B for some years. It was a good car for the PO, but he stopped racing it when the Hoosier tires got fast, because he was spinning bearings due to oil pickup issues. And the regs did not allow addition of the tuma can or sump. So after the last spun bearing incident at Watkins Glen he parked it and bought a 944 to prep for ITS. Other than that, he said, it was a fun car to track.

First thing I did after getting it and rebuilding the engine was have a dry sump system installed.

I'd suggest a sump, an oil cooler, and less-sticky tires.

As GregAmy says, its about lubrication.. and the amount of work to protect a "DE" car is the same as a "race car", especially if you run sticky tires on long g-force corners.

Drop down to boring, non sticky street tires and your starvation issues will subside.. and so will the fun.

Would you rather fix the race car and enjoy that, or turn the street car into a partial race car instead?

In the 1990s, I ran a Tuna can and a 1/4 qt over on the dipstick with period "sticky" street tires. Ran the same in the 2000s'...

You could go "accusump" but I've heard of cars with those also having issues too..

I lost two motors (well, rod knock anyway) to this even with a tuna can and overfilling. The problem was finally solved when I dry sumped it with the CB Performance pump. I agree with the others that if you stay away from sticky tires it will help, but only for a time.

an accusump will solve this problem also
I ran a track 2.0/4 for approximately 10 years as a trailered race car in wheel to wheel
with an accusump

Eeeeeee....I am not a fan of using an Accusump to Band-Aid a systemic oiling problem.

I know people use them for that, but that's not what they were originally designed for (they were designed for start-up, which is why they typically have shut-off valves, manual or automatic.) I know the manufacturers sell them for oil pickup purposes...but the manufacturers are trying to sell product.

An Accusump is a tool to address a momentary problem, that being lack of oil pressure, either on startup or momentary starvation. It is not a permanent solution. Corners are not always momentary, and each time you use the Accusump it has to recharge to be effective the next time. Eventually, be it a single long sweeping corner and/or a series of corners where the accumulator runs out of charge, it'll bite you.

Running an Accusump dry has happened to me. I had a oil starvation problem with a Dodge 2.2 and I data acq'd engine oil pressure and Accusump oil pressure, and quickly found that the Accusump just couldn't keep up.

The flat bottom of the VW 411/412 engine was never, ever designed for the lateral loads that we're experiencing in racing, and this is exactly why its sibling, the 911 engine, was designed with a dry sump system (which was later carried forward to keep the engine low; go watch the video of the Metzger engine going through dyno testing on a carousel/sled that rotated the thing all ways to Sunday to simulate g-loads).

I don't install Accusumps in my race cars; they are a poor tool for a systemic problem.

I strongly reiterate a deep sump, increased oil volume, and less-sticky tires.

But if you insist...buy the biggest one you can find. And still do the sump and less-sticky tires.

All good advice!!

Fully agree that my priority should be on getting my race car back together and not abusing my street car anymore.

However, one piece of advice I'm least likely to take is crappy tires. I don't think I can bring myself to that. Too addicted to the gees!

I've had another Type 4 hot rodder recommend doing what I can to lighten the reciprocating weight, i.e. used lighter custom pistons and rods, so as to reduce the loads on the obviously overtaxed rod bearings. Anyone else think that is worth the trouble?
(Not intending to wind this motor up severely. Might hit 6000 at an autocross momentarily, but would keep strictly to the rev limit on any track usage.)

Andrew

What oil pumps are available that allow a dry sump but still clear the fan housing?

Aaron mentioned a CB Performance one, but they make lots of oil pump variations. Specific model?

Andrew

CB Performance:

https://www.cbperformance.com/product-p/1745.htm

I'd like to upgrade my next motor to the TP Pump:

http://www.tp-technologie.de/products_dry_sump_oil_pump.htm

Aaron, you like the TP unit over the Autocraft pumps?

Andrew

As best I can remember, only the CB and TP pumps work with the stock fan shroud. The TP pump needs slight mods to the shroud (larger gears) while the CB pump fits behind with minimal fuss. Both need modifications to the stock motor mounts to allow the oil hoses to pass through.

an accusump can work... especially if a dry sump is not allowed in a stock class

I'm using the CB pump; it clears the stock 914 fan shroud.

I agree the Accusump can help. I'm just stressing that it doesn't resolve the underlying problem, it only covers it up short-term. Only when you can run safely run the car flat-out on a skidpad for 5 minutes is it truly resolved.

Belts and suspenders. Do it all.

I'm about to put both of these in the Classifieds; figure I'd give this thread first crack at it.

Age is uncertain; the included new parts are from "Johnny's Speed & Chrome" which has been out of biz for a good ten years now, I'd guess. No gaskets are included.

No clue on price, I'm open to ideas. PM me for thoughts. If not interested, no worries, I'll post in the Classifieds.

I'm planning on using a "tuna can" for my street car, which may see a rare Track Night in America appearance on Firestone Firehawk street tires. I ran once it w/o a tuna can last year and did not observe any problems...but then again, I wasn't really watching for the oil light.

https://www.youtube.com/watch?v=mS-Cbn3mJY4

Greg

Thanks for the sump offer, Greg, but I've already popped for one from SCAT.

On another tack for helping oil starvation, I was taking to Chris Foley about this issue on the phone and he mentioned seeing someone that had welded vertical plates onto the front and back sides of the oil pickup bell to slow the flow of oil from side to side in the sump. Has anyone else seen that? Anyone got pictures of what that might look like?

Andrew

I think Chris actually has one; I think it was he that showed it to me?

Are there any instructions available showing how to convert a type IV to dry sump?

Jim

None I'm aware of. The engine part is easy: just get a bolt-in oil pump. CB Performance makes one:

https://www.cbperformance.com/product-p/1745.htm

The rest is all bespoke for your install. You'll need to mount a tank some place; I'm using a Canton from Summit:

https://www.summitracing.com/parts/ctr-23-110r

...and then install it in a convenient location. Then you need lines from the pump to the tank, and from the tank to the pump. Mine's installed up front with the cooler and filters, with AN braided-steel lines going through the passenger side of the cockpit.

Alternatively, you could source and install the 914-6 dry sump tank; there are many threads on doing that, as it's a common process when /4 are converted to 911 engines. That info will have line routing, tank mounting, etc. The only deviation is your lines would be going to the /4 pump. That's likely what I personally would do for a street car.

GA

Is plumbing needed to bottom of engine, maybe to tuna can to scavenge oil from engine? How does system work? If oil pump is used to pressurize oil into the engine, what pulls oil from engine to the tank?

I currently have AN 10 braided lines between engine and front oil cooler. Maybe I can front mount a tank and utilize these lines.

Can someone diagram the oil flow for me?

Thanks,
Jim

It's easy.

Thay dry sump oil pump is a two-stage pump and is plumbed for two external AN lines: one going from the pump to the sump tank, and one going from the sump tank to the pump.

It's all done internally. One stage of the pump pulls oil using the stock pickup tube and routes the oil to the outlet fitting and then to the sump tank; the other stage of the pump pulls oil from the sump tank and pressurizes the engine. In effect, it routes oil like the stock oil pump, but instead of pickup tube-to-oil cooler-to-engine, it first routes it outside the engine to the tank, then back to the internal oil cooler to the engine.

One stage does all the work of pickup and delivering to the tank, the other stage does the work of recovering oil from the tank and pressurizing the engine. This way your engine-pressurizing stage is always using the tank reservoir of oil to deliver to the engine and doesn't have to worry about pickup tube starvation. If the pickup tube starves during cornering then no problem-o, since all that's doing is repleneshing the tank. As long as you have sufficient tank reserves for the pressurizing stage to access, you never lose engine oil pressure.

The CB pump is bolt on, no engine mods needed, and will fit behind the stock fan shroud. The lines go sideways. Just make sure you're running the right cam gear for it. If I think about it I can take a photo next time the car is on the lift.

With the CB pump, you do need to clearance the pump drive tang that slots into the cam a bit. It's technically designed for a Type I that has/needs a longer tang.

I don't know the answer to that. Chris Foley built the engine originally; I'd ask him about it.

Edit: I briefly recall him mentioning it was "a modified CB pump" so that could very well be the case.

That wasn't a question. The drive tang needs to be modified like any Type I pump does to fit a Type 4.

No external plumbing needed on the crankcase to use the CB dry sump pump (although for my own race engines I do quite a few additional mods). The criss/cross is built into the pump body.
As Greg described, the two external lines connect to the protruding portion of the oil pump. Engine mounts need modification to accommodate the fittings.
The size of the CB pump scavenge stage is barely adequate. Also, the inlet/outlet thread sizes are too small for the fittings/hoses I want to use. Therefore, for my own race engines, I do extensive work on the pump before using it.

I always use -12AN lines when installing front mounted oil coolers. For rear mounted coolers I'll use -10. In my opinion -08AN is too small for external oil systems on a Type 4 engine. I try to remove as many flow impediments as possible so the system isn't working harder than it has to, ie wasting horsepower.

Someone upthread mentioned a pickup mod I like. I have the prototype on a shelf near my welding bench, along with a small stack of cut sheetmetal pieces. I haven't made any fixturing to make assembly quick and easy though. With "wings" attached to the front and back of the pickup bell, side-to-side oil slosh should be significantly reduced.

I'd agree with that, Chris. As I observe the sump tank flow at idle I note that there's a constant stream of oil going back into the sump tank, it never varies.

However, on your race engine that I was using in '19, I'd see the flow back into the sump tank acting in streams and spurts/burps. At first I thought there was something wrong but then I realized the larger pump in the race engine was simply running out of oil in the case to pick up. Which pump are you using in that engine?

That's also why we had to put AN10- to -12 adapters from the CB pump to the AN-12 lines. I gave thought to modifying the oil pump case for AN-12 but in the end it seems to be working adaquately for my <6500 RPM usage.

Pretty sure its the same CB performance pump. Might have a blue cover with a Schadek label.

I will say Tuna can, big giant holes in the windage tray, close the head vents and use a 75-76 oil filler with the big venting, New heads from Len with thermal coatings in the combustion chamber and exhaust ports plus a Raby 9090 Djet cam (runs cooler than a web73. Run 1/2 qt of oil overfilled and away you go. Pay attention to what oil wieght use use as high oil pressure over 35 psi means oil is getting to the cooler. Or do a remote cooler and run higher psi