Some interesting facts about various crankcases

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Sat Jul 15, 2006 6:50 am

So.....
I have this 400ish HP Turbo engine to begin building in the next month or so, so today I decided to dig through the rubbish and find the best case in the pile to do all the tricks to...

I have always preferred the early cases (1700) for my bigger builds just because I have found them to have less issues and also to have a bit better alloy, today I found some traits that yet again proves just how much better these cases are than the later units.

I loaded the Pinz down with 17 cases that **MIGHT** fit the bill for the right case for this project. Most of them were later cases from a stash of 914 engines I bought last year while 7-8 of them were 1.7 cases that I have had in the hold of the warehouse for some time.

So I break out the bore gauges and mikes and the straight edges and go to work. The first case was the highly recognized "GA" series from a '73 914 2.0, this is the case that appeared to be the best until I found a trait that we have seen for quite some time and thats the center of the case registers "sagging". This issue is apparent on most all 2.0 cases, and occurs directly under the cylinder seating surface, when the cases are decked on the mill you can see this portion of the case be cut last by the cutters.

Out of the cases I checked today, all but one of the 2.0 cases failed the tests on this portion of the measuring process.This means that all thoses cases will need the cylinder decks machined to provide a flat surface for the cylinder to mate against. Without this being done uneven deck heights will be a for sure occurance and that even effects the cylinder head torques and can cause head leaks.

It's standard procedure for us to check this spec of the case before assembling one of our engines and make the necessary machine work happen to cure it.

Now for the odd part...

NONE of the 1.7 cases had this issue, even one of them that was seriously worn in other areas did not have this trait...

It's my Hypothesis that in the beginning of the TIV engine that VW did not know exactly how strong the cases needed to be to live a long life, but over time they found out that they could skimp on materials and make the cases a bit lighter duty and save some bucks, it's the way VW and most companies work....

This is just something I thought I would share to yet again shed some light on the fact that just because something is newer, or shinier, or bigger doesn't necessarily mean anything. There is a good chance that some of the cases I tested today had TWICE as much mileage on them than the later cases that were taken from service in the mid 80s, yet the early cases with all the mileage still retained their structure even better.

This brings the question into my mind of just how well the later cases may hold up even after being machined compared to the earlier units that obviously retain their measurements in this area better. This is an area that I have not spent much time or effort analyzing, but I certainly will form this point forward....

Long story short I found the case for the Turbo beast. It ended up being an EA coded 1.7 that had near perfect measurements all around that only needed some scrubbing. I'll do the 911 oil squirters next week and get it out for internal micro polishing so I can start the mock up process.

FYI- 85+% of my engines have been built from 1.7 cases, even my 3 liter.

Wally · Post by **Wally** » Sat Jul 15, 2006 7:45 am

Interesting! Do you suspect material differences or casting differences to be the cause?

I am also very curious how you will install the squirter closest at the flywheel bearing ?

Thanks,
Walter

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Sat Jul 15, 2006 7:55 am

Wally,
I believe it was a materials issue, I am going to take some material samples from the various cases and send them to the metallurgist Monday to try and come up with a better idea.

I also noted that some of the cases are thicker in this area and that some of the "W" 1.7 cases actually have a gussett in this area that no other case has.

The squirter closest to the flywheel is a challenge, but can be done. Last time I did it some welding was used to make the job easier

I'd like to add that I have very few 1.8 cases compared to the others, and that none of them were used in this comparison. I do plan on tearing down a few of the 1.8 engines I have around and seeing how they measure up.

The Turbo case has now been welded in this weaker area and I have added a gussett under the weaker part of the register, machine work will be next. This will now be a standard for all 200+ HP engines.

Passatman · Post by **Passatman** » Sat Jul 15, 2006 8:27 am

After reading all of this jake i am a little bit disappointed that vw that i respect so much would do this. I have one spare 2.0ltr type4 case and one complete engine and i am very disappointed.

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Sat Jul 15, 2006 8:36 am

They did it all the time....

Tingly Bill · Post by **Tingly Bill** » Sat Jul 15, 2006 8:54 am

Dont be so surprised passatman, the sheet metal used to make the car bodies got thinner too, modern VW's are probably as much plastic as they are metal!

Kelley · Post by **Kelley** » Sat Jul 15, 2006 9:19 am

I can see the 1.7 cores starting to disappear more quickly now,,,,,,,,,,,

slowtwitch · Post by **slowtwitch** » Sat Jul 15, 2006 9:55 am

I guess I'll hold on to to my w and ea cases

Funny, someone, awhile back, was looking for a case, I told him what I had and he said that he really wanted a GA case....Oh well

pete

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Sat Jul 15, 2006 10:36 am

I tell people all the time that the 1.7 cases are my favorite, for many reasons... The nice thing is non TIV people think these engines/cases are worthless, so you can find them dirt cheap most of the time...

I built Beth's Super 2 Liter on an EA foundation, the 3 Liter was on a "W" platform and my Bus engine was also an EA..

Unkl Ian · Post by **Unkl Ian** » Sat Jul 15, 2006 10:45 am

How much weight did they save by taking material out of the later cases ?

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Sat Jul 15, 2006 11:10 am

It's not measurable on my shipping scale!

Passatman · Post by **Passatman** » Sat Jul 15, 2006 11:26 am

I know about the body panels tingley bill, i had to redo the whole front of my car a couple years ago because some jerk in a light truck totaled the front of my car ( i only drove the car for 4 month before accident ). The chasis of the mexican beetle are also crap but i have decided to go irs rear end with my car. Jake does cryoing the case help.

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Sat Jul 15, 2006 12:05 pm

Cryoing any ferrous material only does two things..

1- It ages the material, stress relieving it.

2- It enhances thermal conductivity.

Aluminum and other ferrous materials don't benefit as much from Cryo..

DaveB · Post by **DaveB** » Sat Jul 15, 2006 3:48 pm

Where in the process did the 1800 fall? I mean is it more like the 1700 or did they already change to the 2000 case?

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Sat Jul 15, 2006 4:03 pm

The EC and AW cases seem to have 1700 traits.... I'll know more when I measure more of them and have the materials analyzed..

BTW- This is nothing thats really new to us, Len has mentioned it to me in the past as he opens up cases for me a lot of times when my machines are tied up...

I first noticed the 1700 case strength about 10 years ago... Since then I have been paying more attention.