How can I verify the piston size and cam?, 2.2l 6cyl Options

[tornik550]

I recently purchased and received a 1970 2.2l 911e engine that I purchased from someone on this website. The engine looks very very nice. The engine is in working condition and has good compression and leakdown. It has zenith carbs which are obviously not stock. Although the previous owner believes that it has stock pistons and cams, we are not certain. Is there an easy way to verify this? I have the engine out of the car. I am soon going to be removing the valve covers and cam tower covers so if there is an easy way to figure things out- I probably should now.

[tornik550]

I have tried to get better pictures however I was not successful. It does look like there is some sort of dome on the piston. I was able to see the valve pocket on all cylinders. I am not able to see the top side of any cylinders due to the scope.

The picture that Sir Andy posted does look like the bump in the center of the piston however there is definitely at least one valve pocket per cylinder.

The engine supposedly came out of a 1970 2.2l and the case serial is consistent with a 1970 2.2l.


I took the cam tower cover (where the chain tensioners are). I cannot see much of anything on the came cause there is a big nut in the way. Where am I supposed to be looking?

Also, I am not sure if this matters but it was a Canadian engine.

[bigkensteele]

I have tried to get better pictures however I was not successful. It does look like there is some sort of dome on the piston. I was able to see the valve pocket on all cylinders. I am not able to see the top side of any cylinders due to the scope.

The picture that Sir Andy posted does look like the bump in the center of the piston however there is definitely at least one valve pocket per cylinder.

The engine supposedly came out of a 1970 2.2l and the case serial is consistent with a 1970 2.2l.


I took the cam tower cover (where the chain tensioners are). I cannot see much of anything on the came cause there is a big nut in the way. Where am I supposed to be looking?

Also, I am not sure if this matters but it was a Canadian engine.

My cams are at the machine shop now, so I can't remember if they were stamped on the front or rear with the lift and duration numbers. Is there anything on the center of the cam? The big nut you referred to is actually bolted on the cam.

[tornik550]

I just measured the lift on a intake valve. It was .406. Considering that I was told that it was 1970 e engine, the case is a 1970 e and .405 is the intake lift on a 1970 e- I would presume that I have a stock e camshaft.

[roblav1]

I've not been around here long enough to recognize "DWD", but it sounds like you're going down that path. Don't do it! My experience is with early 911's and not necessarily 914's.

What is the engine Type number? It should read 911/01 for 1970-1971 911E. The pistons will have domes and pockets and won't look like the CIS piston shown earlier. Pistons should NOT have a bump in the middle. If a 911E, the cylinders should be Biral - cast iron on inside and aluminum on outside ("light alloy finned jacket") and be 84mm bore. Head gasket will be what they call CE type rather than the earlier 2.0 picture shown.

For camshafts... I have the Porsche Tech Specs booklets in front of me for the 1965-1968 cars and the 1972-1973 cars. I never bought the version for 1969-1971 because there is enough overlap info between the two to fill in the blanks. Anyway, the 1972 E camshaft numbers are:
(L) 901.105.181.00 and ® 901.105.110.05 (That's Left and Right in a 911, not a 914.) I believe the 2.2 E cams are the same.

The cam numbers are protrusions in the castings... on the sides.

If you take the heads off, you risk a lot and must be prepared to fix / rebuild. Exhaust valve guides are typical. You'll disturb the rings too... You'll be in there forever... so don't do it! At least not yet.

As most of us have been saying, get it running on the Zeniths first. Get rid of the RPM limiting expensive rotor. They fail. It seems to me the 914 or early 912 rotors are cheap and work great. Get a decent ignition system (MSD 6L versions will work fine) and a Pertronix and set the RPM limiter at 7000 or so. Robust ignition was always the biggest problem on the early carb engines. The carbs dump so much raw fuel down the intake... so you need a strong spark. With carbs, be sure you change the oil every 3K miles. Don't use synthetic either. You're wasting your money and the old seals typically don't like it.

Get it running! Your most likely problem will be the exhaust valve guides and not anything you're examining now. I've had my share of old 911 engines that I brought back to life... some ended up being real good... others created enough smoke on throttle lift to be excellent mosquito repellants. You gotta love the smell of an aircooled engine with bad valve guides in the morning.

[tornik550]

I've not been around here long enough to recognize "DWD", but it sounds like you're going down that path. Don't do it! My experience is with early 911's and not necessarily 914's.

What is the engine Type number? It should read 911/01 for 1970-1971 911E. The pistons will have domes and pockets and won't look like the CIS piston shown earlier. Pistons should NOT have a bump in the middle. If a 911E, the cylinders should be Biral - cast iron on inside and aluminum on outside ("light alloy finned jacket") and be 84mm bore. Head gasket will be what they call CE type rather than the earlier 2.0 picture shown.

For camshafts... I have the Porsche Tech Specs booklets in front of me for the 1965-1968 cars and the 1972-1973 cars. I never bought the version for 1969-1971 because there is enough overlap info between the two to fill in the blanks. Anyway, the 1972 E camshaft numbers are:
(L) 901.105.181.00 and ® 901.105.110.05 (That's Left and Right in a 911, not a 914.) I believe the 2.2 E cams are the same.

The cam numbers are protrusions in the castings... on the sides.

If you take the heads off, you risk a lot and must be prepared to fix / rebuild. Exhaust valve guides are typical. You'll disturb the rings too... You'll be in there forever... so don't do it! At least not yet.

As most of us have been saying, get it running on the Zeniths first. Get rid of the RPM limiting expensive rotor. They fail. It seems to me the 914 or early 912 rotors are cheap and work great. Get a decent ignition system (MSD 6L versions will work fine) and a Pertronix and set the RPM limiter at 7000 or so. Robust ignition was always the biggest problem on the early carb engines. The carbs dump so much raw fuel down the intake... so you need a strong spark. With carbs, be sure you change the oil every 3K miles. Don't use synthetic either. You're wasting your money and the old seals typically don't like it.

Get it running! Your most likely problem will be the exhaust valve guides and not anything you're examining now. I've had my share of old 911 engines that I brought back to life... some ended up being real good... others created enough smoke on throttle lift to be excellent mosquito repellants. You gotta love the smell of an aircooled engine with bad valve guides in the morning.

Your response makes sense and I think its the best idea. The reason that I was trying to figure out the piston size and cam is cause I figured it would probably be helpful for tuning the carbs. I am much more familiar with 914/4 engines. I thought it might be a similar (easy) process for removing the head- but it clearly isn't so i'm just gonna clean things up and start getting it in the car.

Also, you mention that if my pistons should not have the bump in the middle. Mine definitely have a bump but they look otherwise exactly the same as the 2.2e pistons in this picture. Are the bumps telltale of a certain cylinder or brand?

[roblav1]

Where'd you get that picture?

That little bump usually means CIS pistons (K-Jetronic)... lower compression... not necessarily a specific cylinder. There was a picture of that piston type in an earlier thread. They do not have pronounced valve head pockets like yours does. From that fuzzy picture you showed, yours look like they have pronounced pockets like they should in a 2.2E.

The last 2.2E engine I rebuilt was in 1982. Had the mechanical injection... good power and very responsive to the throttle but awful on fuel... something like 16 MPG highway. Your engine will be fun in a 914 and relatively easy to get it in... just the 2.0 flywheel and clutch.

[tornik550]

I am reopening things cause I think I figured everything out. I had created a similar post on the birds website. After lots of looking and research, I am pretty sure that I know what is going on. I have no intention of changing anything- I just wanted to know what I have.

The pistons and cylinders are 2.7l cis. I suspect the valve pocket wasn't actually a valve pocket and was actually where the valve hit the piston. The crankshaft is also a 2.7l crank with a 70.4mm stroke. I measured the lift at an intake valve and it was about .407 which is very close to the advertised .405 for a stock 2.2e engine. I was also able to jam a scope into the cylinder head and see the part number imprint on the 1,2,3 bank camshaft. It was 9011051810r. Stock 2.2e camshaft part number is 90110518100 so it is almost identical. I am fairly certain that it was an R that I was looking at.

Any insight on this setup? Good, bad... Any idea what the R at the end of the camshaft part number might mean?

[Mark Henry]

So...you have a 2.7, nothing wrong with that. What you are finding is common. The seller likely never knew this, he was just going by a case numbers.
2.7 got a bad rap because of the exhaust and 5 blade fan to meet US emissions. Once that stuff is gone it's a good engine.

I wouldn't sink anymore money in it than needed to make it a runner. If you want a better engine my opinion is to leave this one alone, get it running and then over time get another engine together. Then you can sell this one or keep it as a backup.

[roblav1]

I completely agree with Mark on all points. You also have the makings for a 2.7 RS type engine there. I built one of those for a 72 911T back in 1993 and it was a great engine. You already have the cylinders and crankshaft... the case will not be as strong as a 7R type, but that can be worked around.

But run it as is for now. I'd say it is around a 170-180 HP engine as it sits. That will be fun in a 914.