78 911sc rebuild

[Mysterytrain]

Hey folks,
A while back I posted about my 180K mile SC engine self-destructing. You might recall the story..the distributor seized and sheared off the drive gear. The gear dropped down in the intermediate shaft area and was launched out of the bottom on my case..small 'quarter' size hole. Anyway, I am about to have the engine rebuilt. I had always planned on bumping up the displacement to the Max Moritz 3.2 liter upgrade but after reading some threads here I'm very confused. I'm not going to know how bad things are with the engine until later this month when it is opened up. I intend to keep the CIS system. I've abandon the idea of QQ plates because of all the limitations on driving the car here in NJ. So I have lots of questions. I'm assuming the P&C will need to be replaced, is there a recommended bump up P&C set for this car that will be cost effective and make MV inspectors happy? Sounds like I want to stay around 9.3 or 9.5 : 1 max? Are there recommended exhaust changes that will improve performance and again make the MV happy? I guess I can remove the stock system every two years! I want to minimize cost cutting on the rebuild where things are real important..so I'm planning on a new oil pump, anything else that I should not be tempted to reuse? I have alot of faith in the guy doing the work but the final call on what to replace will come from. I really want this right. I'm a little gun shy with distributors at the moment. I know that new ones will break the budget on this project so my plan is to buy a rebuilt unit or find someone that will rebuild a used unit..any recommendation? Finally, what are your thoughts on saving the case and having it welded?
Thanks in advance, Ron

[Doug Zielke]

Hi Ron,
Before you weld up that case, please post a few good shots of the carnage. TIA.

[Mysterytrain]

Doug,
I've attached a picture of the damaged area. The shot is looking in from the rear drivers side..muffler is to the right. The damage is below the distributor area of the engine.
peace, Ron
http://www.mysterytrain.org

[Mysterytrain]

actually this might be better.

[adamred]

Hey Ron:
Just curious are you willing to post who you are considering for your rebuild? I'm in Jersey too always curious to see who people use here.

Adam

[john walker's workshop]

look weldable. is the chunk still around?

[Mysterytrain]

Nah, the chunk is gone, launched into the great cosmos. Anyday now I expect one of those Mars probes to pick it up.
So it looks weldable? Thats good news. Can it be weld be finished up to look real purdy or will it always have a Frankenstein scar?
Peace, Ron

Adam I sent you a PM

[Grady Clay]

Ron,

Sorry to see that. Never have seen that problem before. It’s good that the damage doesn’t appear to be in a critical location. I am sure there are Pelicans who can advise on the “do” and “don’t” of welding the case. There are some big issues there but don’t be afraid of a scar.

Reading your post, it looks like you are considering many options.
My questions are:
How do you want to use your 911SC? Daily driver, weekends only, DE, or other?
How far afield from stock are you want/willing to go?
Do you know your budget? Don’t necessarily tell us, you just need to know.
What are the details of NJ emissions requirements for your year 911?
BTW, what are QQ plates? Dumb o’l me.

There are lots of Pelicans who can help you with the process information to help you make the best decisions and then help with the technical information to have the project come out best.

Be forewarned, I can be a “Pied Piper” and get you into a semi-legal “wolf in sheep’s clothing” before you blink an eye. I think I also give good council and reality checks. I try and distinguish between the two.

Best,
Grady
gradyclay@hotmail.com

[Doug Zielke]

Nice shots, Ron!
Thank you for sharing, and good luck on the repair.

[Mysterytrain]

Thanks for the replies...QQ plates are historic plates, meaning the car nolonger needs to be inspected but..it becomes a museum piece or show car..hence very limited use (mileage) and is to be driven to and from shows only and in daylight! I figure if I'm going to sink major money into the rebuild I'm going to drive it! So to answer your question it will be a street car, not a daily driver but one that is reliable for long trips. Budget..well I have recovered from the intial sticker shock and I'm aware that this will be somewhere between 8 and 12k. Kinda like buying the car again. I also know that I will have a bad case of 'as long as your in there'. So, I'm sure the little things will add up and push me into the outer limits. After a heart to heart with my mechanic he told me he has a new set of Mahle 98mm nikasil cylinders and that we could mate them with the proper 9.5:1 JE pistons and keep the CIS. Price is right, slightly more then a stock 8.5 set. Sweet! He is unsure as to whether we will need to replace the fuel distributor to a euro version.. any thoughts? I've also read an article on using 964 cam profile for the SC is this something I want to do with this P/C setup and CIS? Also because I will not be going the historic car route I will need to keep the current heat excahnger/cat/and muffler and air pump combo to go thru inspection every two years. Once the state is happy then I guess I will remove the stock exhaust and install an SSI system..any thoughts on that? The key to all of this is that I bump up performance, maintain reliablity and still pass NJ emissions tests! Anyway, thanks again Ron

[Rolf G.]

Hi Ron,

I had exactly the same problem 5 years ago.

The case was welded, but the seam was too thick, so the intermediate shaft drive gear didn't fit.

I ground off some material, which brought the pores in the welding seam to light. I filled in petrol, and it seeped through.

I had it welded again, but same result, so I bought some special aluminium epoxy from Loctite and smeared it into the pores. Perhaps JB Weld is similar.
No more leaking and saved a lot of bucks (or Deutschmarks).

It's not really beautiful, but who cares.




Best regards
Rolf

[Mysterytrain]

Ouch, I was afraid of that. No doubt that the clearance inside the case is very tight. Looks like the welder might need to be an artist!