924Board.org

TonyBray · Joined: 02 Oct 2006 Posts: 47 Location: So Cal

Guys,

I have a 81 924 Turbo that I bought for my kid a while back. The car didn't run when I got it and with your help, I fully refurbished the fuel system and it now starts just fine. We had a smoking issue (thick black smoke) and we resolved that by replacing the turbo. Now we have a white smoking issue when the car warms up. #3 is low at around 80lbs with the other 3 cyls around 150lbs. I'm guessing it's a headgasket leak. After replacing the turbo, I'm not sure I want to pull the head! If I were to do this, I would probably pull the entire engine and do the rings, bearings, etc while I had it out so I would know what I have. The big question is, is it worth it? What will it cost to rebuild the engine myself vs what is the car worth when running right? I already have tons of cash and time tied up in this car and don't want to junk it. But I am sure I can't get what I have in it with it not running right either.

If I keep it, I will buy it off of my oldest boy and probably end up giving it to my youngest when it's done since he will be driving next year and probably will end up doing alot of the work with me. At least if I do that, he get's the experience of an engine rebuild and it's not like I don't have the room. I have a large shop with all the tools needed to make this happen.

Any thoughts or input?

--Tony
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67 912 2.0 Type 4
94 968 Cabriolet
82 924 Turbo

skemcin · Joined: 02 Sep 2003 Posts: 1284 Location: Plainfield, IL

Most folks will likely comment that you will never get out of the cart financially what you put into it. So you are already beyond that point.

So do you cut your loses now or go as you have proposed. Personally, I think you go froward with your plan. I only say that since you seem to have a good feel for the car and know where the issues are. If you had no idea where to start or what the problems are, or what underlying problems you might discover, then it would be different.

My vote is stay with the car.
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924.org (no time to complete)
9249206346 - 89k – new shifter bushings, belts, running well.
9249206347 - 8k – waiting its resurrection, no power at the fuel pump and fuse #7 blows w/power

endwrench · Joined: 07 Dec 2002 Posts: 1631 Location: Victor, Montana

I'd say keep it and fix it. Not worth much the way it is and if you have the tools and space you can probably ring and bearing it for less than $400. The heads are not difficult to work on. If you can find some old coger with a valve grinder you could probably get a basic job done for less than a $100. I think finding rings may be a hassel though. Talk to -nick.

Todd
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'79 924NA. Rebuilt 9.5:1, MSDS header, Mega Squirt Injection, MJLJ-EDIS Ignition, 1.6L Whipple Charger and Intercooler, 10lbs Boost, 944 Trans, Custom HD Clutch.
"simsport" said....superchargers are better than turbos its official!....

Joes924Racer · Posted: Wed Jan 03, 2007 4:09 pm Post subject:

I can get the parts ... & you should definatly do this.
for rings bearing mains & rod plus a head gasket
youll be looking at least 320 bucks ... be prepared
more hidden costs Im sure youll want gaskets such
as for the oil pan and seals for the crank shaft &
oil pump gasket freeze plugs maybe too.
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

TonyBray · Joined: 02 Oct 2006 Posts: 47 Location: So Cal

Ok. I'm pretty much planning on doing the engine and then driving my money's worth out of it. Joes924Racer, how do I in touch with you to figure out parts?

--Tony
_________________
67 912 2.0 Type 4
94 968 Cabriolet
82 924 Turbo

macBdog · Posted: Thu Jan 04, 2007 2:25 pm Post subject:

If you can ascertain that its definitely head gasket leak by means of a leak down test then just replace the gasket. If you woke up early you could get it done in a day and the cost would be minimal.
_________________
1979 931 with a 350 chev
1973 911E with EFI

TonyBray · Joined: 02 Oct 2006 Posts: 47 Location: So Cal

macBDog,

You are saying you can remove the head with the engine in the car? How do you get the exhaust off? I spent 2 days R&R'ing the turbo in that super tight space. I just don't see enough clearance to slip the exhaust manifold off the studs to get the head out.

If you have a procedure, by all means, let me know!

BTW, I just the following info from the Porsche dealer:

head set 156.35 week away
lower gasket set 79.47 week away

rings discontinued
rod bearings discontinued, hard to believe
main set 129.16 week away standard size

--Tony
_________________
67 912 2.0 Type 4
94 968 Cabriolet
82 924 Turbo

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Call EBS Racing for a more "supportive" approach to your overhaul parts.

As for the head, I have heard (from Paul) that it can be done with turbo piping in place. I presume you just remove the manifold nuts and head bolts, and pull it away from the manifold and up.

Also, in addition to Joe's parts list, plan on exhaust studs and nuts (and don't skimp).

This wouldn't be a white 931 from Ebay, would it? I almost bought that one.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

TonyBray · Joined: 02 Oct 2006 Posts: 47 Location: So Cal

Nope, not the white one from E-bay. This one was a local car.

I will get started on this one soon but not immediately. I am just finishing the full suspension rebuild and big brake upgrade on my 67 912 and then my 968 needs a clutch. Once those projects are done, I will move the 924 to my "long-term" bay and get started. Thanks everyone for the help. I will start a new topic if I need more help on the actual removal of the head and what parts to replace and where to get them...

--Tony
_________________
67 912 2.0 Type 4
94 968 Cabriolet
82 924 Turbo

-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

Rings are available through EBS for $100
Standard size rod & main bearings are available through thepartsbin.com for $110/main and $35/rod
Headset is $125 and engine/block set is $90 (includes rear main seal) from partsbin too.
You'll also want to replace the turbo-manifold and wastegate-manifold crush rings ($15/ea).
Add on an engine hoist rental and an engine stand.

If you pull the whole thing, I would highly recommend having the block deck checked for straightness, having the bores checked and running a stone through to take out the glaze if needed, and have the crank journals checked and polished if needed.

Replace the studs in the turbo & manifold with bolts, and it goes together much more easily.
_________________
1980 931S
15psi boost, MS-II, EDIS, 951 IC, custom intake, Ford 5.0L throttle body, Forge BOV, WB o2, G31 w/LSD, 964 wheels, 968 rear sway, Bilsteins, 200# Welt. springs. A laptop, and a partridge in a pear tree.
1991 964 C4 Cabriolet

TonyBray · Joined: 02 Oct 2006 Posts: 47 Location: So Cal

Thanks Nick...

I already own an engine lift, and 3 engine stands. I'm really thinking of being on the safe side and do the full rebuild as opposed to the head only. Seems like the only way to get any money out of this thing by driving and enjoying it.

--Tony
_________________
67 912 2.0 Type 4
94 968 Cabriolet
82 924 Turbo

-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

^^ ah, then you have no excuses

_________________
1980 931S
15psi boost, MS-II, EDIS, 951 IC, custom intake, Ford 5.0L throttle body, Forge BOV, WB o2, G31 w/LSD, 964 wheels, 968 rear sway, Bilsteins, 200# Welt. springs. A laptop, and a partridge in a pear tree.
1991 964 C4 Cabriolet

TonyBray · Joined: 02 Oct 2006 Posts: 47 Location: So Cal

Nic,

I just noticed your long sig... We should talk. I have the MSII and EDIS system already for another project that I have temporarily aborted. I also have a nice little eaton supercharger as well. If I am going to keep the car for a long while, maybe a switch to EFI is a good idea.

Did you document anything here or somewhere else when you did yours?

--Tony
_________________
67 912 2.0 Type 4
94 968 Cabriolet
82 924 Turbo

-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

I just followed the MS directions then experimented from there. The MS documentation and defaults should get you close enough to start it up and run.

Endwrench went the supercharger route with his MS-I. Min is the other 'squirter on the board with a MS-II.

EDIS is dead easy with the MS-II. Getting the trigger wheel adapted to fit was the only somewhat tricky part. The rest was plug & play for me. Although, my stock tach isn't working and I haven't traced wires to find my mistake yet...

It is, however, a _very_ slippery slope!
_________________
1980 931S
15psi boost, MS-II, EDIS, 951 IC, custom intake, Ford 5.0L throttle body, Forge BOV, WB o2, G31 w/LSD, 964 wheels, 968 rear sway, Bilsteins, 200# Welt. springs. A laptop, and a partridge in a pear tree.
1991 964 C4 Cabriolet

TonyBray · Joined: 02 Oct 2006 Posts: 47 Location: So Cal

Theres a small diode thing needed to get the tach to work with the EDIS. I know that much but I can't tell you exactly what needs to be done. I had already heard about this from the 914 guys who did it.

What are you using for a fuel rail and injectors? Did you mod the CIS intake or fab your own?

--Tony
_________________
67 912 2.0 Type 4
94 968 Cabriolet
82 924 Turbo