RJUSMC

I just pulled the engine on my '87 951 today. I've got some time, but I'd really like to see a comprehensive checklist of the "while I'm in there" stuff. I've seen a lot of conflicting information out there and I'd like some sort of consensus on the most important things that need to be fixed. Mostly, I'm just looking for advice on everything I should replace or upgrade for the rebuild.

Here's the goal: I'm not building a track car, I just want a fast-ish version of the 944 I know and love. The biggest mod I'm looking at right now is the LR 300 WHP package. But if my turbo is shot, I could talk myself into just upgrading the turbo now (never, ever want to remove the crossover pipe again). I'm definitely replacing all the obvious seals. I'm not really sure which fasteners/studs etc. need to be replaced/upgraded and if aftermarket or OEM is appropriate for which.

• Connecting rod bolts (ARP worth it?)
• Rod Bearings
• Oil cooler seals
• Ignition wires
• Alternator (maybe?)
• Turbo (rebuild) <--not sure how to tell if it needs it.
• Head rebuild kit (pelican)
• Block rebuild kit (pelican)
• Motor Mounts
• Throttle Body Rebuild

Sensors?
Harnesses?
Other Seal kits?
Clutch looks fine but while I'm in here...

I'm also interested in beautification

• New hardware with yellow-zinc (McMaster-Carr)
• Venturi delete and new vacuum hoses
• Silicone Hoses (LR)
• Wire harness looks like it came out of a Russian tank from WWII, but it works.

Of course, budget always gets a vote.
I know a lot of you out there have a lot of experience with this, this is my first Porsche rebuild, so I want to do it right.

kev951

Can you post or send me a picture of the bare engine bay? I'm looking specifically for where the DME harness (fuel injector) is mounted to the firewall if any and a general picture of all the hard brake lines and associated clips along the firewall. Thanks in advance

moalaska

If you are going to pull the engine or do any major work, there are a massive amount of things that you should do that gets expensive.

Upgrade your turbo. If it's original 26/6 it's old anyway
Clutch
Look at your exhaust manifold, it may be cracked.
Water pump, timing belts
Head and block are usually good
Throttle body is easy to rebuild but can be done any time.
Venturi delete.
Put new connectors on wiring harness!!!!

RJUSMC

Hope this helps.

RJUSMC

Like, replace ALL the wiring harness connectors? I haven't heard that one yet. Why not just replace the whole thing then, or is that getting super pricey?

50Lombardy

I have a somewhat related question on an engine rebuild I'm doing on a 951 with 65,000 miles. The engine has cylinder scoring in two cylinders and is using oil. I have a 300 HP Lindsey Kit that I'm using almost exclusively on the street. I've spoken to three reputable engine rebuilders who have given me very different specs. One says the rods and pistons should be reused if possible. He also says there's no need for crank balancing for this build, but that the pistons and rods should be balanced. A second builder wants to change the pistons but reuse the rods. A third says that both pistons and rods should go because there are far more efficient and lighter options to use. The second two would balance the lower end as well. Two of the builders will do the work for about $6K to $8K. The third is nearly twice the price so that pretty much rules him out. You views on the minimum machine work that should be done for a good quality, reliable street build would be appreciated. Most importantly, is it acceptable to reuse the pistons and rods if they are in acceptable condition? That would save a significant amount on the rebuild.

kev951

Thanks @RJUSMC, I'm guessing the oval round shaped hole in the firewall / bulkhead is where the DME harness grommet goes and then routes up to the firewall. I was hoping to see if it then gets mounted anywhere to the firewall at that point because there is a Adele clamp on my harness and I'm assuming that goes somewhere lol. The picture is very helpful and will hopefully get me where I need to be because my engine bay is completely stripped and everything is going back on. Unfortunately it's been many years since I've taken it all apart so I need some kind of a guide or reference and your picture will help a lot! And thank you for your service!

moalaska

There is a new one available now, I think it's well over $1000. I rebuilt mine, depends on what you want to do and how much time you want to spend.

GPA951s

The Wiring harness does not get mounted to the firewall, From the factory it has a big wire Loom holder that attaches to the back of the engine.

As far as the engine rebuild: I would not hesitate in any way to re-use the rods.. It would be wise to get new Serrated Nuts for the rods.. . I re-used turbo rods for a track car build and that engine has been living between 4000 and 5800 RPM for the last two years with no issues. So for the street its a no brainer.
I have re-used pistons in the past, but I didn't touch the bores.. just new rings. If you have a scuff in the wall and it needs touch up then just go 1st oversize, Wossner pistons with rings and wrist pins are only $600 ( Call Karl Poetl at racers edge) Not sure where you are located but you need to find someone who can do the Alu-sil honing.
Factory head studs are fine for the street, a widefire Headgasket and call it a day
As far as the harness, just clean it really well, inspect all the connections, I have only ever had to replace the injector plugs (Lindsey) has a kit for that, as well as the reference sensors.. those tend to crumble.
If you are planning on having Air Conditioning in your car now is the time to change all the O-Rings, Esp the two on the firewall, you cannot get to them with the engine in.
Clean everything really well, you also might want to get a full set of ex Gaskets, the downpipe and the pipe off the turbo take bigger crush rings than the header to crossover and the Wastegate. Also there are TWO different size Doughnut (really mushy and fat) gaskets you should replace one is crossover to WG and the other (the bigger of the two is WG dump to main Ex. .(If you need Misc parts I use Mark at Germanaustoparts.com.. if things aren't listed just give him a call.. He will help you out. and he also owned these cars and still has a 968).
If you have a Hydraulics shop near you, I would convert the oil cooler lines to Stainless Steel with AN fittings. They don't leak and the whole setup is cheaper than one factory hose. But you need the adapter fittings. You need to get the Loctite 574 as well for the Crank Girdle and BS.
As far as the Turbo, Call Tim at Tims turbos... He can make what you have work.. I have a turbo off my 86 that he turned into basically a Cup turbo..
Just a quick TIP … When you re-assemble the crank girdle, put the oil pump on and just draw it up hand tight... This locates the crank girdle properly so that it is totally "Flush" with the front of the block.
If your Crank has a "groove" in the back, you can take the spring out of the rear main seal and shorten it. (it screws into itself) Take your old one and practice.
Put in a new Pilot bearing in your crank as well.
Goto Autozone and get a can of "right stuff" RTV sealant. Use that in the corners of the pan. when you mount it.
Look up Van Svenson on youtube, and watch his videos on rebuilding his 44 engine.. Not a turbo but most of the same stuff applies.
Hope this helped.. - Good Luck..
P.S. Unless you are planning on having the block honed properly, Do not touch the bores with anything other than a clean soft cloth. (As me how I know THAT one..!) 20 years ago I was in your boat..

RJUSMC

@GPA951s Excellent! This is exactly what I was looking for. Thank you!

GPA951s

Happy to help, and this is also a Good time to do the "Urethane trick" on the Transmission mount.. Look up the thread, I did it on my car,, ZERO additional vibration, and VERY strong.. and the Kicker is that it only costs about $30 …
Also, when you Re-install the engine.. mount your crossmember loosely and then measure from the backside of the crossmember to a castor block bolt hole.. (I use cheap plastic Giant Harbor Freight Calipers) This way your entire driveline will be "square" and you wont have a fight on your hands when you install the Trans and the Half shafts..
Think about Slotting the Bellhousing as well, you can then Gap the sensors with a feeler Gauge on the stand... then slide the BH on.. Also if you ever have an issue down the road much easier to take the BH off if needed. I was able to switch a clutch disk with a friend helping on my lift in an hour and a half... start to finish..
you can install with crossover on. But when it comes time for the front ex part and the WG set everything in, draw it up hand tight, then once everything is in place torque it down.
If I think of anything else Ill post. ..OH.. Get some "fire sleeve" and run your power wire to the starter in it as well as the WG hose..

kev951

Thanks again @GPA951s My factory harness has 2 loom clamps (Adele clamps) on it and I am trying to figure out where they go (if both go on the block). Would you have any pics of info on that?