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Literati914
I picked up a complete 2.0+ engine today, came with all sheetmetal, alt, starter, fan, twin Italian 40 IDF carbs, etc. The seller got it second hand from a disabled N. Texas guy who'd crashed his 'real nice orange 914 with spoilers'...he remembered that it was built in Ft. Worth TX and said that it was over-bored but could not remember the details - said "it was built to a 2 point something" confused24.gif headbang.gif . Said the PO seemed honest and assured him that it was a fast, strong engine. It has a GA engine number. He was asking $700 for everything and I figured at the very least it was a descent price for a 2.0L + dual 40IDF webbers, so I bought it. I've asked some locals if they knew anything about it and none did.

Whats the general concensus, just do a leak down test, compression test and use it if within spec... or break it down and start taking measurement?

EdwardBlume
QUOTE(Dougster @ Apr 2 2018, 03:49 PM) *

I picked up a complete 2.0+ engine today, came with all sheetmetal, alt, starter, fan, twin Italian 40 IDF carbs, etc. The seller got it second hand from a disabled N. Texas guy who'd crashed his 'real nice orange 914 with spoilers'...he remembered that it was built in Ft. Worth TX and said that it was over-bored but could not remember the details - said "it was built to a 2 point something" confused24.gif headbang.gif . Said the PO seemed honest and assured him that it was a fast, strong engine. It has a GA engine number. He was asking $700 for everything and I figured at the very least it was a descent price for a 2.0L + dual 40IDF webbers, so I bought it. I've asked some locals if they knew anything about it and none did.

Whats the general concensus, just do a leak down test, compression test and use it if within spec... or break it down and start taking measurement?


What a good buy!

Build a test stand and run it, or pop in after a full service on the valves, fuel lines, belt, etc, might not be a bad idea to test the alt while its out.

It's not hard to take a motor in and out.
Boomingbeetle
See if she runs! Personally I'd want to pull a head and measure bore and stroke, that would definitely help if you're looking to sell it (in or out of a car). But you will likely be doing some teardown anyway if it doesn't run... Or you can connect a graduated cylinder to a compression tester hose, fill the motor cylinder with oil, turn it by hand and measure displacement of the motor cylinder on the graduated cylinder gauge. multiply x4 and you've got a very close estimate of displacement
Literati914
Just out of curiosity what's the largest /4 configuration that would use a pair of 40 IDF webbers and not need bigger ?
VaccaRabite
On 40s? maybe a 2300 or there abouts. But I'm guessing at a 2056 since that keeps the stock crank.

Zach
rgalla9146
QUOTE(Boomingbeetle @ Apr 2 2018, 07:07 PM) *

See if she runs! Personally I'd want to pull a head and measure bore and stroke, that would definitely help if you're looking to sell it (in or out of a car). But you will likely be doing some teardown anyway if it doesn't run... Or you can connect a graduated cylinder to a compression tester hose, fill the motor cylinder with oil, turn it by hand and measure displacement of the motor cylinder on the graduated cylinder gauge. multiply x4 and you've got a very close estimate of displacement


I agree.
Literati914
So..bdc on compression stroke and fill the cylinder til the oil just wants to touch the threads of the spark plug hole? Marvel mystery oil or reg dino or doesn't mattee? ... I suppose the specific amount poured into the cylinder would be verification for what was pumped out. Assuming that the rings are healthy, all oil will be evacuated on the upstroke, right? No need to worry about excess left in the cylinder? Is there a special graduated beaker for this purpose?
r_towle
Bolt it in, drive the shit out of it.
@700 bucks you can’t lose.
Larmo63
agree.gif

That's what I was thinking. Is the engine clean and tidy? The cleaner it is, the lower the miles it has on it.

Pictures?
porschetub
Check it over out of the car ,give it a clean if needs be,replace rocker cover gaskets after checking valve clearances,check over the carb linkage and make sure both carbs are even on the linkages,clean air cleaners etc etc,all this work is easier out of the car.
I purchased my 911 motor with ZERO history,only thing I knew was the plugs were a good colour and the motor was clean,turned out to be a great running motor count myself as being very lucky.
Treat this motor as a total unknown,when you have got it running change the oil and filter after its fully warmed up,good luck.
falcor75
You can measure the stroke with a piece of wood or tig welding rod thru the spark plug hole by compairing the bottom/top position of the piston. It wont be 100% accurate but should give you an indication of its a stock 71 mm stroke or a 78 mm stroke.

Other than that, change the oil and filter, adjust the valves, set the timing and fire it up.
TheCabinetmaker
Rich said it right!
maf914
QUOTE(falcor75 @ Apr 3 2018, 01:06 AM) *

You can measure the stroke with a piece of wood or tig welding rod thru the spark plug hole by compairing the bottom/top position of the piston. It wont be 100% accurate but should give you an indication of its a stock 71 mm stroke or a 78 mm stroke.


It may be time to resurrect the famous chop stick thread. laugh.gif
TheCabinetmaker
QUOTE(maf914 @ Apr 3 2018, 09:16 AM) *

QUOTE(falcor75 @ Apr 3 2018, 01:06 AM) *

You can measure the stroke with a piece of wood or tig welding rod thru the spark plug hole by compairing the bottom/top position of the piston. It wont be 100% accurate but should give you an indication of its a stock 71 mm stroke or a 78 mm stroke.


It may be time to resurrect the famous chop stick thread. laugh.gif

Nooooo! Well, maybe yes. Always need a good laugh!
Literati914
I didn't mention, the long block is intact and was mounted on an engine stand when I picked it up, the accessories and tins are all in boxes. The engine is not freshly rebuilt either, you can tell it was used before the car was wrecked.. there's some of the typical grime on it that you see on a used engine. I expected it to be cleaner. The seller said he was going to soda blast the engine and paint the cylinder fins. The fins are kinda rusty looking. That sounded like a good idea but got me thinking, is there any reason an intact pre-assymbled engine can not be blasted before installation? Tape up intake ports? what else? I know getting it started is first priority but I plan on purchasing a blaster soon for general restoration anyway. I'll try to get some pics later today.
Boomingbeetle
QUOTE(Dougster @ Apr 3 2018, 07:42 AM) *

I didn't mention, the long block is intact and was mounted on an engine stand when I picked it up, the accessories and tins are all in boxes.


If that is the case definitely pull the head and measure, piece of cake!

If you ever use the graduated cylinder method on any engine, you'll need to glue a hose fitting into the bottom of a 1,000cc graduated cylinder, attach it to a hose that is screwed into the spark plug hole, then fill the cylinder with oil all the way up through the hose and into the graduated cylinder maybe to the 200cc mark. Ideally you want the motor cylinder to be at Bottom-Dead-Center on the compression stroke but that is hard to get perfect. That's why I say start with 200ccs in the beaker before you begin, in case you aren't at bottom. Also make sure you are on compression stroke or the oil will exit through the valves. Turn the motor by hand and look for the difference between lowest cc volume and highest. if it is 500-CCs, you have a 2.0
porschetub
QUOTE(Dougster @ Apr 4 2018, 02:42 AM) *

I didn't mention, the long block is intact and was mounted on an engine stand when I picked it up, the accessories and tins are all in boxes. The engine is not freshly rebuilt either, you can tell it was used before the car was wrecked.. there's some of the typical grime on it that you see on a used engine. I expected it to be cleaner. The seller said he was going to soda blast the engine and paint the cylinder fins. The fins are kinda rusty looking. That sounded like a good idea but got me thinking, is there any reason an intact pre-assymbled engine can not be blasted before installation? Tape up intake ports? what else? I know getting it started is first priority but I plan on purchasing a blaster soon for general restoration anyway. I'll try to get some pics later today.


In a way its good the tins are off you can check for oil leaks top and bottom of the barrels,don't worry about corrosion on the barrels that's normal.
Really do take some pics of the motor it will help people advise you better.
r_towle
I would never blast an assembled motor
That stuff gets everywhere.
Unless you plan to put a heat disapating coating on the cylinders, there is no value aside from knowing they are currently not rusted.
Clean up the tin, powder coat that. Those should be done now, all at once.
That is well worth it.

If not knowing is going to drive you crazy, pull off the heads and measure your motor properly. It’s a few hours of work to do right.
Then setup the valve train geometry to make it as good as it will get and smile with you great purchase.
Literati914
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Literati914
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Literati914
95.9mm bore

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Literati914
71.28mm stroke

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Literati914
Chunky Push Rods, looks like aluminum ?

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Literati914
valves = 35.42mm & 41.86
Plugs = Bosch Platinum 'WR7CP'
r_towle
Looks like a 2.0 liter
Dave_Darling
You mean 2056, right? 96mm bore by 71mm stroke...

--DD
Literati914
QUOTE(r_towle @ Apr 3 2018, 10:14 PM) *

Looks like a 2.0 liter


96mm bores x 71mm stroke, does that equal a 2056 displacement? all be it the bores are technically 95.9 so ever so smaller...
BTW, the piston tops are dished. Do they come that way stock? and, those are not stock push rods are they?
Boomingbeetle

[/quote]

96mm bores x 71mm stroke, does that equal a 2056 displacement? all be it the bores are technically 95.9 so ever so smaller...
BTW, the piston tops are dished. Do they come that way stock? and, those are not stock push rods are they?
[/quote]

That is 2056cc if you calc it. The dished pistons may or may not be stock depending on year and CR of the motor. You can calculate that too, an Internet search will tell you how. Those are indeed stock aluminum pushrods for the type 4. Big difference from type 1 bug motors.
falcor75
[quote name='Boomingbeetle' date='Apr 4 2018, 07:06 AM' post='2595900']
[/quote]

96mm bores x 71mm stroke, does that equal a 2056 displacement? all be it the bores are technically 95.9 so ever so smaller...
BTW, the piston tops are dished. Do they come that way stock? and, those are not stock push rods are they?
[/quote]

That is 2056cc if you calc it. The dished pistons may or may not be stock depending on year and CR of the motor. You can calculate that too, an Internet search will tell you how. Those are indeed stock aluminum pushrods for the type 4. Big difference from type 1 bug motors.
[/quote]

Ummm, how can the pistons possibly be stock if the cylinders have been upgraded to 96's? The pistons are most likely aftermarket aswell is my guess.
Boomingbeetle
QUOTE(falcor75 @ Apr 4 2018, 01:34 AM) *


Ummm, how can the pistons possibly be stock if the cylinders have been upgraded to 96's? The pistons are most likely aftermarket aswell is my guess.


Doh! That’s what happens when you post to the forum way past bedtime! My guess is that they used a big-bore bus engine kit for the lower compression dished pistons. They look pretty clean, so the motor is likely rebuilt as OP says. Can you still see cross-hatch in the bore?
Dave_Darling
You'd have to measure the piston dish and the combustion chamber volume, plus the deck height, in order to calculate the compression ratio. I don't know that there were any "Bus kits" specifically with low compression, but it is possible.

The pushrod in your photo above is aluminum and is stock. The steel pushrod tube retaining wire will rub a notch in the softer aluminum pushrod if you don't seat it against the "lip" on the end of the tube...

--DD
Literati914
It didn't dawn on me, but you could have a low compression and a hi-compression 2056... Lot's of people do 2056 when rebuilding a 2.0, is it usually with dished pistons or flat tops? Why would you want low compression - besides turboing? Is there a problem with valves hitting piston tops or something? Is it that some people want to use low octane fuel? Is there an advantage to it? ... also would the extra volume that the dish creates increase the displacement, technically?
jcd914
I have never seen dished 96mm pistons until these pictures but obviously someone made them.
All that I have seen were flatop including the set in my shed.

The OE 2.0L pistons were dished. Bus pistons had the biggest dish, US 914 2.0 pistons a smaller dish than bus and Euro 914 2.0 pistons had smaller yet.

Valves hitting the pistons is a possibility depending on the valve lift, valve diameter and cam profile.
Usually valve pockets are cut into the pistons to prevent contact rather than dishing the piston tops.

Jim
Literati914
Do these valve diameters look stock = 35.42mm & 41.86 ?

Been looking, I can not find any dished 96mm pistons..maybe these are old and no longer in production?

Questions: All other things being equal, what will dished pistons in a 2056 do for performance vs flat tops? I mean low compression is going to produce a weak low end torque, right? But overall HP should be the same as w/ flat tops? Will it rev as well as a higher comp engine?

What kind of HP/torque can usually be expected from a 2056 anyway
Literati914
OK well, stock 2.0L pistons are 94mm, right? and I know the US versions were dished...so, wouldn't the stock bores measure something like 95.9mm (my quick and dirty measurement), to account for rings ? I'm feeling like these dished pistons are stock and if that's the case, then this engine is stock and not overbored. Is this plausable ?
jcd914
No stock 94mm 2.0L cylinders measure right about 94 mm, pistons are slightly smaller.
I don't know the specific sizes but I can look them up.
The rings are recessed into the ring grooves in the pistons.

Jim
Literati914
IF you guys bought a 2056 and discovered it had dished pistons (low compression), would you want to replace them with flat top pistons, for a spiritedly driven street car that may participate in autocross from time to time ?

There's a local guy who's got a set of 2.0L 96mm pistons and cylinders for $75, that I could pick up. I've got a message out to him inquiring of the condition.
Boomingbeetle
I think you will need to measure head cc and deck to find your compression ratio before you decide. Maybe they dished the pistons because the heads or cylinders were milled down in a rebuild and CR was too high. Also those flat pistons might not have the same wrist pin size or location to line up with your rods. You’d have to take one off the motor to compare. $75 is a good price though depending on make.
Spoke
I bought a 2L "mystery" engine with dual Weber carbs as well. My goal was to build it into a 2056 engine with 96mm pistons.

When I took it apart, I found out the pistons were already 96mm and have the dished pistons like the OP.

Instead of taking it completely apart and rebuilding with new 96mm pistons, I tried putting it all back together and trying it out. Cleaned up the case, bolted it back together, reinstalled the carbs without rebuilding, and it ran like a champ. The engine is in the car and runs real good.
porschetub
QUOTE(Dougster @ Apr 15 2018, 06:31 AM) *

IF you guys bought a 2056 and discovered it had dished pistons (low compression), would you want to replace them with flat top pistons, for a spiritedly driven street car that may participate in autocross from time to time ?

There's a local guy who's got a set of 2.0L 96mm pistons and cylinders for $75, that I could pick up. I've got a message out to him inquiring of the condition.


Don't place too much importance on the dished pistons ,the difference in power won't be that much unless you have a highly modified engine,go with what you have as spoke pointed out,for a street motor you have the benefit of the lower compression helping it to run a bit cooler,IMO fuel quality isn't what it used to be.
Dave_Darling
Either trust that the previous builder knew how to calculate compression, or take it apart and measure all of the pertinent volumes so that you can calculate compression. Then you can decide if flat-top pistons would help or not.

I personally think you should just run it...

--DD
Literati914
QUOTE(Spoke @ Apr 15 2018, 10:10 AM) *

I bought a 2L "mystery" engine with dual Weber carbs as well. ...

When I took it apart, I found out the pistons were already 96mm and have the dished pistons like the OP.



Wow! someone else with dished 96's !! They do exist ! I thought I was in the twilight zone. I have not been able to locate any mention of them, much less a picture (so thanks for posting). Do you remember if yours have a the divit in the center? Doesn't matter I guess, just wondering. Yea, I guess I'll bolt mine back together and try to enjoy.

Question though - cylinder honing: should I bother? I don't remember seeing crosshatching (kind of didn't pay close attention/in a hurry), I think there was some carbon build up on one of the cylinder walls. Can it be DIY'ed with the harbor freight hone that fits on a drill? if so... replace rings or re-use?

Also, this engine certainly has some oil leaks. I'll be getting the viton seals for the tubes but I noticed the "head gasket" rings that fit between the cylinders and heads were kind of crappy, you could see an un-even seal on them (narrow area of carbon) on one side/edge. And they didn't seem absolutely round and their fits into the recess on the head were not perfect. Is that normal ? Is there a preferred replacement for these? Likewise, is there a similar seal used on the cylinder/block end? 'cause it's probably oilier at that junction..
bbrock
QUOTE(Dougster @ Apr 19 2018, 10:44 PM) *

Question though - cylinder honing: should I bother? I don't remember seeing crosshatching (kind of didn't pay close attention/in a hurry), I think there was some carbon build up on one of the cylinder walls. Can it be DIY'ed with the harbor freight hone that fits on a drill? if so... replace rings or re-use?


I can't say whether you need to hone, but I had a bit of rust in a cylinder on my engine that was stored in humid sheds for too many years. I honed it out with the HF hone on a drill. Worked great.

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Literati914
QUOTE(bbrock @ Apr 20 2018, 08:44 AM) *

I honed it out with the HF hone on a drill. Worked great.


Thanks Brent, I think i'll just plan on that then.. mine may have been some rust too, but didn't seem major. As for rings replacement..I'm not sure that I could even find the correct rings if I want to replace them since these particular pistons are soo rare.

Anyone have info/recommendations for the 'head gasket rings'? and/or seals at the cylinders/case junction ?
Literati914
Ok, from what I'm starting to understand, what I'm calling "head gasket rings" is technically referred to as "sealing rings".. and apparently the latest wisdom is to not use them unless necessary. I read that VW recommended removing them at some point. Also, it sounds like there is a "shim" at the other end (cylinder to case), that is used to adjust the compression ration. Do I have this right ?

I am going to measure the CC of the head using plexiglass/syringe/oil. Then, I assume I can get the CC of the dished piston with the same method, right ? I do plan to do that w/piston installed btw. Then how does one get the current deck height number/? using simple digital calipers while spacer tubes are bolted down over the long head studs?
porschetub
QUOTE(Dougster @ Apr 21 2018, 06:22 PM) *

Ok, from what I'm starting to understand, what I'm calling "head gasket rings" is technically referred to as "sealing rings".. and apparently the latest wisdom is to not use them unless necessary. I read that VW recommended removing them at some point. Also, it sounds like there is a "shim" at the other end (cylinder to case), that is used to adjust the compression ration. Do I have this right ?

I am going to measure the CC of the head using plexiglass/syringe/oil. Then, I assume I can get the CC of the dished piston with the same method, right ? I do plan to do that w/piston installed btw. Then how does one get the current deck height number/? using simple digital calipers while spacer tubes are bolted down over the long head studs?


Good call on the honing,remember if you can feel any grooves with your fingernail the barrels are toast.
Grant or Hastings rings are pretty good,pretty sure they do 96mm check the websites.
Best to get your heads cleaned and checked over also,they may need work.
bbrock
I don't know that there is consensus on the head gasket. I don't remember details from reading those old threads except that at least one knowledgeable person said the VW recommendation to remove them was for a specific application (only bus maybe?) and didn't apply to us. The only other part I remember was that after all the reading, I decided I will be installing them when my heads go back on, but would love to hear opinions as it is a decision that I'll be making soon as well.

Tom Wilson's book has a good description for measuring deck height. It's worth having if you don't already.
Literati914
Yea I found this VW bulletin..
http://www.ratwell.com/mirror/www.dolphins...m/techbull.html
it specifies certain G engines but not the GA (which is what I have), so maybe that IS just bus engines. Would be nice to understand why the recommendation for eliminating them on some engines and not others. Anyway, I'm ordering Tom Wilson's book now, thanks.
MarkV
QUOTE(bbrock @ Apr 21 2018, 10:28 AM) *

I don't know that there is consensus on the head gasket. I don't remember details from reading those old threads except that at least one knowledgeable person said the VW recommendation to remove them was for a specific application (only bus maybe?) and didn't apply to us. The only other part I remember was that after all the reading, I decided I will be installing them when my heads go back on, but would love to hear opinions as it is a decision that I'll be making soon as well.

Tom Wilson's book has a good description for measuring deck height. It's worth having if you don't already.


There is lots of information about the pros and cons but I think the consensus is not to use the sealing rings. They are prone to blowout failure, I didn't use them on my rebuild. I lapped the cylinders to the heads with valve lapping compound.
bbrock
QUOTE(MarkV @ Apr 21 2018, 11:47 AM) *

QUOTE(bbrock @ Apr 21 2018, 10:28 AM) *

I don't know that there is consensus on the head gasket. I don't remember details from reading those old threads except that at least one knowledgeable person said the VW recommendation to remove them was for a specific application (only bus maybe?) and didn't apply to us. The only other part I remember was that after all the reading, I decided I will be installing them when my heads go back on, but would love to hear opinions as it is a decision that I'll be making soon as well.

Tom Wilson's book has a good description for measuring deck height. It's worth having if you don't already.


There is lots of information about the pros and cons but I think the consensus is not to use the sealing rings. They are prone to blowout failure, I didn't use them on my rebuild. I lapped the cylinders to the heads with valve lapping compound.


Do you have to compensate for removing the head sealing ring with shim rings at the base of the cylinder?
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