Overbore with a 2.2 Crank? That is the question

[2 Fast 4 U]

As I have been asking questions, and got some fine answers, about replacing the crankshaft in a 1.9 engine, with one from a 2.2. [I would like to add that this will [and has to] be a very, very low budget project.]

I would like to use the 1.9 pistons and rings [stock high compression type], but how do I know if the rings are not worn out too much?

I know from years back when I had a 350cc twinn 2 stroke JAWA motorcycle, one could measure the gap of the rings fitted in the cylinder [without the piston], the only thing needed was to buy new piston rings, does this also work for measuring the rings of the 1.9??

If the rings are worn too much, is it necessary to overbore to the next size rings and piston or are there oversized rings that can be used with the existing pistons

Should I be able to use oversized rings do I have to do any thing with the cylinder wall, like roughen it up or can I let them be like they are??

[opelnut10]

Originally Posted by 2 Fast 4 U As I have been asking questions, and got some fine answers, about replacing the crankshaft in a 1.9 engine, with one from a 2.2. [I would like to add that this will [and has to] be a very, very low budget project.] I would like to use the 1.9 pistons and rings [stock high compression type], but how do I know if the rings are not worn out to much? I know from years back when I had a 350cc twinn 2 stroke JAWA motorcycle, one could measure the gap of the rings fitted in the cylinder [without the piston], the only thing needed was to buy new piston rings, does this also work for measuring the rings of the 1.9?? If the rings are worn to much, is it necessary to overbore to the next size rings and piston or are there oversized rings that can be used with the existing pistons Should I be able to use oversized rings do I have to do any thing with the cylinder wall, like roughen it up or can I let them be like they are??

If you are going to use the 2.2 crankshaft you will have to bore the block and use new pistons because the 2.2 is 10 mm longer stroke and 2mm bigger bore the 1.9 pistons and are the wrong pin height and will come up out of the hole too much. The least expensive method is to find a a set of Opel CIH 6 cyl. pistons with the right bore and stroke. In the US I have used 255 cubic inch Ford V8 pistons at +.040 for an overbore of .060 on the 1.9 block or .080 to take it out to the full 2.2 liters with the 2.2 crank. It will also require the small end of the 1.9 rods to be made larger for the Ford piston pins which are .916. Hope this helps

[GTJIM]

Originally Posted by 2 Fast 4 U ....replacing the crankshaft in a 1.9 engine, with one from a 2.2. [I would like to add that this will [and has to] be a very, very low budget project.] 1)I would like to use the 1.9 pistons and rings [stock high compression type], but how do I know if the rings are not worn out to much? I know from years back when I had a 350cc twinn 2 stroke JAWA motorcycle, one could measure the gap of the rings fitted in the cylinder [without the piston], the only thing needed was to buy new piston rings, does this also work for measuring the rings of the 1.9?? 2)If the rings are worn to much, is it necessary to overbore to the next size rings and piston or are there oversized rings that can be used with the existing pistons 3)Should I be able to use oversized rings do I have to do any thing with the cylinder wall, like roughen it up or can I let them be like they are??

1) The 1.9 pistons cannot be used with the 2.2 crankshaft since the pin is positioned higher up to allow for the longer stroke - you must use 2.2L pistons. Though the rods are the same length - best to use the earlier, forged, 1.9L rods if you have them.

2) The pistons and rings need to be the same bore size - bigger rings won't fit the smaller bore - though it is possible to use just slightly over-size 0.005" O/S rings in standard bores for better ring gap. They must be filed to fit.

3) Modern rings don't need the bores to be honed - it is even thought to be bad practice to hone them! However the lip at the top of the bore needs to be removed and the bores honed if wall damage is evident.

HTH

[tekenaar]

Originally Posted by opelnut10 If you are going to use the 2.2 crankshaft you will have to bore the block and use new pistons because the 2.2 is 10 mm longer stroke and 2mm bigger bore the 1.9 pistons and are the wrong pin height and will come up out of the hole too much. The least expensive method is to find a a set of Opel CIH 6 cyl. pistons with the right bore and stroke. In the US I have used 255 cubic inch Ford V8 pistons at +.040 for an overbore of .060 on the 1.9 block or .080 to take it out to the full 2.2 liters with the 2.2 crank. It will also require the small end of the 1.9 rods to be made larger for the Ford piston pins which are .916. Hope this helps

. . . uh, not quite! . . . stroke is 7.7mm (77.5mm - 69.8mm) longer and CIH 6-cylinder cranks share the 1.9's stroke, 69.8mm, so pistons cannot be used with 2.2 crank for the same reason, pistons will stick 3.85mm out of cylinders at TDC!

Last year I advised a friend in Maylasia who had problems sourcing oversize pistons for his 2.8 CIH-6, 92mm bore x 69.8mm stroke. I suggested that he instead bore his block 1.0mm (.040") oversize to 93mm and buy six standard size 1.9 pistons, the most common of all CIH pistons . . . he did just that and one of the very few classic Opels in Malaysia is back on the road again, I'm happy to say!

[jeff denton]

It's just not that big of a deal to order up custom pistons spec'd out to do what you want them to do. They don't cost that much more than stock Opel pistons.
Whenever lack of funding is the reason for shortcutting and foregoing the process of building an engine right, the project is sabotaged and doomed from the get-go!
We know how to get the ultimate short block built. It's all right here in the threads. We brainstorm new methods (mostly different parts, actually) constantly, but what you see so far is beyond good enough for most of us.
I just don't see a lot of future in trying to get great performance out of stock rods and pistons. Their place is in the engines that power the purist's perfectly restored cars. The biggest market here, although even these guys still want more power...
Trouble is, once we get a solid, screaming bottom end built, what do you do for a head? We're limited again, but our forward thinking members are working on it, too. They can get you steered into decent street performance. We are there, big time. But the next step? Again we have a problem with finding, making, and modifying the cams and lifters and rocker arms to match what we've done downstairs, that is, get the absolute ultimate out of the 1.9/2.2, etc.
Again I'd like to see or cause more effort and research and commitment to making the head work. The roller rocker project and the roller cam idea is key to the future of CIH performance, but we have to want it badly enough to make it happen. I discovered that offering to throw money at it and make it available wasn't appreciated. At that time the only reason I personally needed them was for cheating, which I lost interest in. Even lost interest in the whole racing class my Opel was built for. Along with half the class, which is what happens when cheating is allowed or ignored, which is the same thing.
Anyway, The bottom end is done. The recipes are here, just follow them. It's easy. If you find it isn't easy, you need a more open minded (but very basic) automotive machine shop that can think beyond what they commonly work on, and apply these skills to a funny little German car.
It's all the same. Just building an engine. Making parts fit and work.

[opelnut10]

Jeff, you are on the right track IF everyone was wanting to build an all out race motor that will be required to run wide open or nearly wide open for a given period of time. IF it needed to be turned 8000-8500 RPM in order to pull the gear ratio it is running. IF it is torn down and checked at least at the end of every racing season and the oil changed after every race. But most of us just want to make it as reliable as possible, make enough power to move it along nicely and show what can be done without hiring a research & development team, putting the car in the wind tunnel, etc. or spending a LOT of money buying parts and pieces that are totally unusable or unneed on a street driven Opel just to say "hey look at me, I got MORE"(IMHO)

[jeff denton]

Exactly! Only a few of us want to go that far and won't give up when the present level of reality kicks in.
Other than that, what I was pointing out was that the recipe for reliability is yours for the asking right here in this website. What goes in our race cars for a hundred laps at 8,000 rpm will tickle the heck out of our street rodders for years of enjoyment at 6500 rpm. Bottom line, or bottom end, same thing! On a budget not at all unrealistic compared to scrounging and throwing together junk and blowing up motor after motor in that persuit to almost keep up with traffic in the fast lane. It can be done, right? That was my point.
Read all about what con rod and piston to use in the threads, buy them, build or have built your short block, and enjoy it. But it has to be done right, regardless, assembling junk and foregoing even the basic correct procedures is pointless unless we have a competition going to see how shabbily we can get by and for how long! I, personally would not enter that contest but some of our fellow members obviously would and apparently are, thus these discussions offering little pointers on how to do things right. It becomes a comparison of right and wrong, a justification of expenses, and a personal choice as to where on the scale you want to be. Surely none of us want to be accused of overly criticizing or belittling others' attempts, I think lots of us just want to help our friends prevent problems caused by excessive frugality or just ignorance/lack of experience.
I got a kick out of a TV show recently that was a competition between NASCAR engine shops to show us how rapidly they could assemble a $50,000 engine. About half an hour, if I recall correctly, but they did point out that they wouldn't dare actually race that thrown together pile of expensive parts. Their team mates show us every Sunday how quick they can change tires but quite often one falls off...

[2 Fast 4 U]

As I said this has to be a VERY, VERY LOW BUDGET rebuild I have the following engines to work with:
1.6 S, 1.9 S and a 2.2 E [the "S" engines are high compression]

I want to make an engine that has more torque [without having to take the engine to a machine shop]. I have been told, engines with a longer stroke have more torque.

In the headgasket thread Rally Bob said that the stock 2.2 head has almost the same flow than a race ported 1.5 or 1.6 head,

Originally Posted by RallyBob Well, one nice thing about the 2.2 head is that as-cast with standard valves, it flows almost the same as an all-out race-prepped 1.5/1.6 head. It has lots more potential when modified. Stock 1.5 head, about 80 cfm. Stock 2.2 head, 122 cfm. Race-prepped 1.5, about 124-125 cfm. Race-prepped 2.2 head, 145-150 cfm. I like the 2.2 cranks because they're the lightest of the bunch (about 34 lbs), while a 1.9/2.0 crank is usually 36-36.25 lbs, and a 2.4 crank is 43 lbs.

and because the 2.2 head already has hydraulic valve lifters and hardend valve seats, I use LPG [= Liquified Petroleum Gas] as fuel, so hardend valve seats is a must, I wil use the 2.2 head, [don't worry, I already have the 1.6/1.9 carb manifold modified to bolt up to the 2.2 head, only need to make Rally Bob's modifications at the top and base of the manifold]

The 1.9 "S" engine has 90 PS/5100 RPM torque 149 Nm/2500-3100RPM
If I make the stroke longer, I will increase my cylinder cc to about 2100 cc [according to Otto], and because of the longer stroke the torque will also go up and that is what I would like.

Now comes the part that worries me a bit, because of the larger stroke I will have to loose some material off of the top of the piston, accordig to Otto, the pistons will stick 3.85mm out of cylinders at TDC.
3.85mm is a lot of material and I still have to make the gaps for the valves.

I can do 2 things:
1 loose 3.85mm off of the pistons
2 loose 0.15mm + one extra headgasket off of the head and make a 4mm steel filling piece
Both options are work intensive.

But this is going a bit further then I want at the moment, I think that I have to fit the 1.9 pitons on the 2.2 crankshaft first and see for myself how much the pistons stick out of the cylinder.

But comming back to my question, and why I started this thread:

How can I measure the piston rings to see if they are not wornout to much?
I know that I'll have to measure the cylinderwall as well for wear.
If the rings are wornout to much and the cylinder not much can I suffice with new rings?
If both [rings and cylinderwall] are worn, are there rings avalible that have a bigger outer diameter to fill the wear so I can use the stock 1.9 pistons I have??

[jeff denton]

Normally we start with determining whether an engine needs "overhauled" or "rebuilt". Big difference, and it starts with answering the question, "how much taper does the cylinder wall have?"
I want none. But there is always some, because of how an engine works, more specifically, what the rings do and when and why. How much taper you want to work with is up to you, but you must understand why I want none, again it is all about how the rings work.
What you may need to do it your way, that is, use 1.9 pistons with a 2.2 stroke, is discussed in radical buildup threads that mention the need for a "spacer plate". You're on to that by mentioning really big head gaskets. But none of us have taken Opel performance to that level yet, that I know of, although Hiro is close by using the diesel block's taller deck, same thing... I realize that level of performance isn't your goal but the part required is the same and it exists only in our fantasies or the diesel block, neither of which are an option in your case dictated by a budget.
So as you know, the other method is to cut down the piston where it would interfere with the head, and then deepen the valve reliefs. I don't know if that's possible, given the thickness of the crown, plus:
Another method is shorter rods but that's just silly, the rods are too short already and surely would cause skirt/counterweight interference, which, who knows, may already be an issue using the 1.9 piston anyway, because the real problem is the pin height of the 1.9 piston. Fixed by using the 2.2 piston which must have the pin height and skirt length (they go hand in hand) proper for the 2.2 stroke.
Hope this makes sense.

[Paul]

Originally Posted by 2 Fast 4 U If the rings are wornout to much and the cylinder not much can I suffice with new rings? If both [rings and cylinderwall] are worn, are there rings avalible that have a bigger outer diameter to fill the wear so I can use the stock 1.9 pistons I have??

You can't swap worn piston rings among different pistons from which they were originally installed or from a different bore from which they were originally installed. If you attempt this, the rings will not seat in the new cylinder and the rings will probably break in short order.

So... that much being said, you should select a short block with the best compression. You can if you wish disassemble the engine and clean all tahe parts. While its apart you could measure the cylinder bores at the top and bottom and in directions 90 degrees apart. You must use a set of telescoping micrometers and not calipers. From this you can check for taper and out of round wear. This will only give you an indication of the condition of wear and how much longer the engine will hold compression. I would not even hone the bore lightly as you will change the fit of the ring to cylinder.


However, all this work would be nothing more than an excersie in learning how use the porper measuring tools correctly.

[2 Fast 4 U]

@ Jeff: It makes sense, but I don't understand it yet, I'll have to read it a few times and translate a word or two

Taking off the top of a piston is not a big problem, even deepening the valve reliefs, should be doable, but having enough flesh on the top to withstand the force its undergoing is a whole other ballpark.

I'll do a search on the "spacer plate" and see what has been written on that subject, but I'm a long way from that.

First I have to see what happens with the 2.2 crankshaft

[2 Fast 4 U]

I have found the way to see if the piston rings, cylinder walls are worn to much, I'll post the numbers in the next days for the 1.6 and 1.9 engines.

[2 Fast 4 U]

I have looked at the threads about "spacer plates" but nothing has been done as in making one, so maybe I'll be the first with a thin "spacer plate"

[jeff denton]

Any easy way to look at the effect of cylinder wall taper on piston ring performance would be to put a bare ring squarely into the cylinder just below the top ridge. Measure the gap. Now put the same ring way down low in the cylinder, near the bottom. Measure the gap. Big difference? Then there's a lot of taper. Think about what that ring is doing as it goes up and down, it has to move a lot to conform to the varying bore diameter. And the gap is becoming excessive at the top, where you'd rather it were the smallest. As it's doing this the seal between the ring face and the cylinder wall is becoming lesser and lesser near the ring's gap.
Not to mention the piston can rock more at the top because of excessive clearance, this causes less ring face surface contact with the wall, also.
Oh, how I wish there were 2.2 and 1.6 parts around here to experiment with!
If you have the 2.2 crank installed with the 1.9 rods and pistons, go ahead and stack up head gaskets until you have proper clearance. See if it will run like that, and for how long. I'm curious!

[2 Fast 4 U]

Originally Posted by Paul You can't swap worn piston rings among different pistons from which they were originally installed or from a different bore from which they were originally installed. If you attempt this, the rings will not seat in the new cylinder and the rings will probably break in short order.

It was not my intention to swap the rings.

Originally Posted by Paul So... that much being said, you should select a short block with the best compression. You can if you wish disassemble the engine and clean all tahe parts. While its apart you could measure the cylinder bores at the top and bottom and in directions 90 degrees apart. You must use a set of telescoping micrometers and not calipers. From this you can check for taper and out of round wear. This will only give you an indication of the condition of wear and how much longer the engine will hold compression. I would not even hone the bore lightly as you will change the fit of the ring to cylinder. However, all this work would be nothing more than an excersie in learning how use the porper measuring tools correctly.

The problem is with the engines I have, I do not know anything about these engines so I'll have to take them apart anyway

[2 Fast 4 U]

Originally Posted by 2 Fast 4 U I have found the way to see if the piston rings, cylinder walls are worn to much, I'll post the numbers in the next days for the 1.6 and 1.9 engines.

ring gap [without piston] in cylinder:
1.6 engine 1st 2nd ring 0.30-0.45 mm [0.0118-0.0177]
1.9 engine 1st 2nd ring 0.35-0.55 mm [0.0138-0.0217]
3rd ring 0.38-1.40 mm [0.0150-0.0550]

taper and out of round wear max 0.013 mm [0.0005]

[2 Fast 4 U]

I read in the workshop handbook that if the piston pin is pushed out of the piston, the piston can not be used again is this true??

[hrcollinsjr]

Originally Posted by 2 Fast 4 U I read in the workshop handbook that if the piston pen is pushed out of the piston the piston can not be used again is this true??

Don't know. I got ready to assemble an engine once that the machine shop had reversed the piston on the rods. They pressed them off and turned them around and we never had any trouble. These weren't OEM pistons but I doubt that would make much difference.

Harold

[tekenaar]

Originally Posted by 2 Fast 4 U I read in the workshop handbook that if the piston pen is pushed out of the piston, the piston can not be used again is this true??

. . . looks like the writing is on the wall!

[2 Fast 4 U]

Reading an other thread, "2.2 crank in a 1.9 block" I came across this written by opelnut10:

Originally Posted by opelnut10 Hard to come by, but adds a lot of torque to the engine comparted to the 1.9 crank. My suggestion is to have the 1.9 crank welded and offset ground to a 3 inch stroke, use the 1.9 rods (pre-74) and use a set of dish top pistons 73 up) you will need to have the pistons cut .125 which will make them flat tops with valve reliefs. With .060 overbore this will yield about 2100 cc and add torque to the engine. With a big valve head and street hyd. cam this combo will make about 125-135 HP and is a pretty inexpensive build. [ http://www.opelgt.com/forums/opel-en...tml#post102417 post #5 ]

I foregot to mention that I also have a 1.9 N engine [low compression], so could this work for me as wel??

[2 Fast 4 U]

Originally Posted by tekenaar Originally Posted by 2 Fast 4 U I read in the workshop handbook that if the piston pen is pushed out of the piston, the piston can not be used again is this true?? . . . looks like the writing is on the wall!

That is what you get when a person is a "Multi Linguist"

[GTJIM]

Originally Posted by 2 Fast 4 U As I said this has to be a VERY, VERY LOW BUDGET rebuild I have the following engines to work with: 1.6 S, 1.9 S and a 2.2 E [the "S" engines are high compression] I want to make an engine that has more torque [without having to take the engine to a machine shop]. I have been told, engines with a longer stroke have more torque.

Since you have a complete 2.2E motor the first step is to find out how worn it is. You may only need new rings, bearings and gasket sets to 'fix' it good enough for a street use motor.

[2 Fast 4 U]

Originally Posted by GTJIM Since you have a complete 2.2E motor the first step is to find out how worn it is. You may only need new rings, bearings and gasket sets to 'fix' it good enough for a street use motor.

I know, but looking at the numbers opelnut10 put down:

Originally Posted by opelnut10 Hard to come by, but adds a lot of torque to the engine comparted to the 1.9 crank. My suggestion is to have the 1.9 crank welded and offset ground to a 3 inch stroke, use the 1.9 rods (pre-74) and use a set of dish top pistons 73 up) you will need to have the pistons cut .125 which will make them flat tops with valve reliefs. With .060 overbore this will yield about 2100 cc and add torque to the engine. With a big valve head and street hyd. cam this combo will make about 125-135 HP and is a pretty inexpensive build.

I think that I'll get more out of the 1.9 with a 2.2 crankshaft then a 2.2 with a carb, and even if I get less I'll have a self made engine

[opelnut10]

Originally Posted by 2 Fast 4 U Reading an other thread, "2.2 crank in a 1.9 block" I came across this written by opelnut10: I foregot to mention that I also have a 1.9 N engine [low compression], so could this work for me as wel??

NO it will not work because the piston will still come up out of the bore too far with the 2.2 crank. You have two choices with the parts you have, use the 2.2 pistons & crank with the 1.9 block and rods (which will force you to have the block overbored 2mm) or use the 2.2 block and pistons with the 1.9 rods (if they are the early forged rods). Running on LP gas keeps the combustion chambers & valves very clean compared to gasoline and it is higher octane than gasoline (a least in this country) so you can run more timing. 2.2 crankshafts are easier to come by in Europe than here because they were never imported here. The 1.9 block/2.2 crank is the combo I run in my GT with a 1.9 head with 1.84 intakes and 1.5 exhaust and a cannon manifold with a 350 cfm Holley 2 barrel. With the cam I run it made 153HP at the flywheel which is a nice streetable combination.

[2 Fast 4 U]

Originally Posted by opelnut10 NO it will not work because the piston will still come up out of the bore too far with the 2.2 crank.

You had a 1.9 crankshaft welded and offset ground to a 3" 76.2 mm stroke, that is only 1.3 mm 0.051" less than the 2.2 stroke [77.5 mm].

You used dish top pistons and cut 0.125" off of the pistons which will make them flat tops with valve reliefs, 0.125" = ±3.18 mm, my question can I cut off 0.67 mm ±0.027" more to get the number mentioned by Otto and that is 3.85 mm ±0.152" and still have a sound piston top with valve reliefs??

Originally Posted by opelnut10 The 1.9 block/2.2 crank is the combo I run in my GT with a 1.9 head with 1.84 intakes and 1.5 exhaust and a cannon manifold with a 350 cfm Holley 2 barrel. With the cam I run it made 153HP at the flywheel which is a nice streetable combination.

As for the head I'm using the stock 2.2, [as Rally Bob mentioned it flows almost the same as a race prepped 1.5/1.6 head] inlet valves are 45 mm 1.77" and exhaust valves are 40 mm 1.57".