I pulled an all nighter on getting my other engine torn apart, finally got it done and clean. I know for a fact that the design and engineering are there, but after taking apart it seems almost simple in operation.

A friend of mine works at a machine shop that can bore the aluminum, and I asked him about replating it, he said get some details and he'll see. I'd like to go with the plating again instead of sleeves (afterall it would be close to free since it's "his" engine he's building). From what I've read of the replating, that would save close to a grand, if his shop can do it. If any of you guys (generic term, girls can reply also ) can give me as specific details as possible of the plating...chemical compositions, is there a certain process, temperature of mixture...anything that can help him figure out if they can pull that off. I've gone through the tech manuals process for honing, but pretend I haven't. Picture me trying to rice it to hell and explain the right way to do it. I've been putting off fixing the car up for too long. If I wait any longer there may not be too much of a car left to fix up (yeah, bad shape). Also any tips or techniques on building 944 engines are also welcome. Thanks.

 

Steel sleeves require new pistions. Can't use the steel coated pistions from the stock 944.

Boring oversize requires an etching process to raise the grain in the aluminum.

Manuals say if there is insignificant scaring that you just ring the pistions. No honing.

 

I rebuilt my race motor and did not do any honing. No need as the cylinder walls looked fine even after 140k. I put it back together and am making solid power in my class.

 

a few yrs ago ,that process could be done at a m dealership, don't know how many can do it now, but its worth a shot to look into .

 

My pistons are VERY fried. The engine had over 240k on it...it went out because the thrust bearing (#3 journal) wore down enough that the crank counterweight hit the back of the block. Locked it up tight. Luckily I was at a stop light, at idle, with the clutch in; by the same token, I was at a stoplight stopped, backing up traffic. Moderately embarassing, because "breaking down always happens to someone else." So new pistons were an already given, sorry, I should have mentioned that earlier. #3 cylinder has a scarred area about 1.5 square inches, it looks like the piston tilted slightly in the bore. #1 has short vertical scares all the way up and down the bore. I wish my digital camera were working...let a friend borrow it and he managed to let condensation build up inside on a trip, awaiting repair.

So let me rephrase what I meant to say earlier. Boring/very, very heavy honing are required to my block (more than the +1mm the book shows). Like I said, the plating is preferrable over sleeving, but I don't have a problem with the sleeves.

 

Around here complete used engines can be had for about $1000 (long block). That might prove cheaper than the fix. Other alternative is a complete parts car.

If you must rebore then you could consider a large bore 2.8L motor. It would not be cheap, but you may have a great donor block. Worst thing is that this process may take some time.

 

Got lots of time. I bought and installed a replacement engine, so it's still on the road. I thought the 2.8 required the use of a 968/944S2 crank? Putting the bore @ 102.5mm would give me just a hair over 2.6, and if I could get a 968 crank with the 102.5 bore it would be an even 2.9L. Enough dream talk, can't afford a 3.0 crank. What is the maximum bore that can be done on the block. Wasn't Anderson going to 104 or 106 on his 3.1 engines? Keep the options coming.

 

Just got off the phone with my local Porsche expert repair shop and his advice is this.
if the bores are in good shape, just rering the pistons using a little atf as a lite oil to allow the rings to seat.
No nead to hone them. as mine are in nice shape, this is what I will do.
the procedure for boring and lapping the cylinders is in the manual and I can email you that if you like.

cheers
Lance