Text by Rainer Cooney, Ken Daugherty, Alan Klingen, Ron LaDow
[Editor: After 50 years or more, 356 sump plates often leak. Here is a range of solutions to the problem from some of the veterans on 356Talk, as posted in November, 2008.]
Alan Klingen: Over the years the plate develops waves on the sealing surface from the nuts pulling it down. When the plate is off I lay it on a flat steel surface, such as an anvil, with the inside surface up and hit the stud holes to flatten them back down. You should also check the center copper rivet to see if has become loose. If you need to use a sealant use a non-drying one that be cleaned off at the next sump service.
Ken Daugherty: We 'flatten' sump plates by turning them upside down of an anvil, placing the ball end of a medium size ball peen hammer in the stud hole and carefully smacking the hammer with another hammer. This reforms the dimple caused by repeated tightening over the years. Caution, do wear safety glasses in case ...
By Barry Lee Brisco
The 356 engine is often described as "air-cooled", but a more accurate phrase would be "oil-cooled". After all, cars with radiators are "water-cooled" even though ultimately that water is cooled by the air.
With that in mind, it's easy to understand why 356 owners are concerned about their oil temperatures during hard running on hot days. If the oil gets too hot, engine damage can occur. But how hot is "too hot"?
Starting in 1950 (Ludvigsen, Excellence Was Expected) or 1951 (Johnson, Authenticity Guide) an oil temperature gauge was standard equipment. Up until mid-1957, the various gauge types over the years — first MotoMeter, then Stork, and finally VDO — had numbered scales that ended at 250F / 121C (MotoMeter, shown at right) or 280F / 138C (Stork, shown below right). At around the time of the T1 / T2 change in mid-1957 the numbered temperature scale used in the VDO "combi" gauge—oil temp and fuel level—was dropped and a simpler scale was use...
By Joe Leoni
If you think your oil temperature gauge is not giving you an accurate reading, most likely either the oil temperature gauge or sender has failed. However, there is a third case where the sender and gauge are not compatible. The indication would be that the oil temperature shows hot with a cold engine, then the temperature decreases as the engine warms. [Editor: Brad Ripley emphasizes that currently available VDO senders will not work with an original gauge. New senders from Porsche (made by Beru) that will work look different and cost plenty.]
First, some background on the sender location in the engine compartment. In mid 50's and later cars, it is located just behind the distributor. In earlier cars it's hidden behind the fan shroud. Brad Ripley writes: "On late 2-piece case engines, the sender is threaded in the engine case above the flywheel. On early 3-piece case engines, the sender is threaded in the case at the lower left corner. Starting with ...
What oil filters will fit on a 356?
All of the following will fit:
AC P203, C315
Bosch - OX79
FIAMM FB1254 (Italian)
Fram C3P, PC10, C-988
Hastings LF130, 102
Knecht EN 108
Mann PF915, PF915N
Motorcraft FL 144
NAPA "Gold" 1010
Purolator PM3003, PM352, P70AC, T110, L20701
Wix 51010, PC10
List gleaned from the 356Talk Discussion List, largely from Mike Robbins, with additional input from Wulf Mšnnich and Stephen Dean.
Let me know if you find other compatible oil filters and I will add them to the list. Email Barry Lee Brisco, Website Technical Editor, at firstname.lastname@example.org .
And Don't Forget the Gasket...
David Jones, Process Analyzer Specialist with Premcor Refining offered the following information on oil filter gaskets:
"Be aware that the gasket supplied with some of these filters is not a rubber or neoprene type. The one with the Mahle ...
Recommendations from 356Talk Members
(Ken Daugherty:) One method to clean the 356 oil cooler is to turn it upside down, fill with lacquer thinner and let soak overnight. In the morning, drain it and then refill with Simple Green or Bleche White and let soak for another day. Then drain it and rinse thoroughly with hot water until it runs clear. Blow it out and refill with WD40 (it is a water dispersant) and drain and blow dry. Fill with clean motor oil and let stand until ready to use.
(Wyatt Blankenship, Tom Martinez, and other recommend:) Lanfried Ultrasonic Cleaning, 20730 South Main St, Carson, CA. Contact: Jerry Marquez. Tel. 327-8930.
(Alan Klinger at The Stable says:) Send it to Ultrasonic Cleaning in Carson, CA. They will get it absolutely clean, clean enough to FAA certify it. If you could see the process they is no way you can replicate it. They flush and filter the effluents with special solvents and they check the flushed solvent for de...
By Charles L. Navarro Provided courtesy of LN Engineering
Summary: What oil should I use in my 356?
[Ed: The question of "What oil should I use in my 356?" is often asked. Below is what Charles Navarro suggests, depending on whether you want to use traditional oil or a synthetic formulation.]
When in doubt, look at the label. Do not use an API SM or API CJ-4 motor oil in your Porsche 356. Also, it is best to use an oil that does not need supplemental additives!
Inexpensive Dino Oil: Kendall GT 20w50 or Castrol GTX 20w50 (or it's High Mileage formulation). I'm not a big fan of GTX, but if changed often, it's okay.
Good Dino Oil: Valvoline 4-stroke motorcycle oil 10w40 or 20w50. This oil is easy to find and comes with an API SF/SG/SJ rating.
Best Non-Synthetic Dino Oil: Swepco 15w40 "306" motor oil. Many shops who had been using Mobil 1 have switched to this and most if not all their problems (including bearing failures) went away.
Best Semi-Synthetic:Brad Penn Racin...
By John Wilhoit
We performed four comparisons using our latest 1925TR 356 engine with a stock Dansk muffler, the NLA Dansk Supersound muffler, the Bursch 1.5" header (with street muffler and race stinger), and the WR 1925TR Sport muffler. These tests were performed at Carobu Engineering in Costa Mesa, California, on their DTS engine dyno, in February 2007.
The 1925TR is very streetable but is by no means a mild engine. The peak power is at 6000 rpm and peak torque is around 5000 rpm. These are recorded during a full throttle sweep from 3200-6500 rpm in which the performance is recorded and calculated by the dyno at 100 rpm intervals.
The dyno also plots the fuel curve at 100 rpm intervals across the entire run using a lambda sensor. In the 356 engine there is always a dip (richness) in this curve just below peak torque, which is made worse by the use of a sport cam. The tuning and back pressure of the exhaust can help this (as you'll see in the tests), but it can't...
Everyone has their favorite muffler in terms of the sound it produces. But have you ever wondered how your favorite muffler stacks up in terms of performance? Thanks to Alan of The Stable in San Francisco, you don't have to wonder any longer.
Let's let Alan take it from here....
Click an image to view it full size
Here are the results of my dyno test of 4 common mufflers used on the 356. The first one is the stock unit with its tail pipes. Second the Bursch street legal system that has the large oval muffler in it. Third the Euro sport system that is just straight pipes with a couple of resonator boxes in it looks very much like the 4 cam "Sebring" system. The last system is the Porsche "sport" type, which has a couple of tail pipes that exit under the body works.
The test motor is a fresh rebuild 1600S, 356A, that is stock except for the NPR pistons and cylinders, Elgin 6607 cam much like a 356C cam, port matching, stock distributor set to 36 degrees ma...
By Maurice P. Cruz, the Phillipines
Start-up / Break-in Guidelines
1. Spin engine without spark plugs to circulate the oil before start-up.
2. Use Bosch W6BC spark plugs (.46" extended tip electrode) or W5AC
3. Valve clearances : a. on a new engine, set at 0.008" for all valves for the first 30 - 50 miles b. then set valves to 0.001" more than standard or; c. after break in : set intake at 0.005" set exhaust at 0.007" (Ed: note that factory clearances are .004" intake and .006" exhaust and are preferred by many)
4. For break-in, set timing to TDC. After 2000 - 3000 miles, reset dynamic timing to 30 degrees total advance at 3500 RPM.
5. Keep RPM below 4000 - 4500 for first 500 - 1000 miles.
6. Drive at low but variable speed at cool temperatures
7. Oil temp should not exceed 210 degrees
8. Change engine oil and clean screen/magnet at : 50 miles, 300 miles, 1000 miles, 2000 miles, and thereafter...
Harry Pellow: Try the Maestro's Patented "Binary Search" procedure to find your miss. This technique will narrow the problem down to the individual cylinder (orside) that's bad in two minutes, making it much easier to find and fix the problem.
Before you do the test, you might want to check that the plug wires are installed properly on the correct plugs, the plugs are clean (or new), and the timing (low and high speed) are in the right ballpark.
First find a flat, straight road with no traffic. Go there.
Go to engine. Disconnect the downcoming linkage rod to one carburetor.
Drive car on one carburetor. It'll drive poorly of course, but a good 356 oughta get up to 50+ mph, given long enough and flat enough. If it does do 50mph, stop.
Connect the linkage arm you disconnected and disconnect the other one. Drive on the other carb. If one side only does 25-30 mph, you have a bad cylinder on that side.
Stop. Get out an...