924Board.org

keith · Guest

Hello there.

I am close to engine installation (1980 931), and want to renew those items that aren't easily accessible in the chassis. This is a used engine, but I figured I'd AT LEAST replace the rod bearings while it was on the stand... Any other items or seals that I would be better off addressing at this time?

keith · Guest

also - this would include problem areas common to this engine...?

Zuffen · Posted: Fri Sep 07, 2001 4:17 am Post subject:

What is the mileage on the engine? What was the oil pressure like? I think the biggest pain is the pan gasket leaking especially off the front pump.

These engines aren't like the 944 were you have to replace the engine seals and the cam tower gasket every four years. I'm exagerating but not really.

I would leave the engine alone. The bottom end of these things is nearly bullet proof. Just replace the pan gasket. And maybe rebuild the turbo oil lines and the wastegate before installing.

If the engine is old you should crack it open and replace the head gasket, then while your in there refresh the head. If you plan on boosting it look into installing studs now and not later. It is alot easier with engine out to set the head back on.

_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

Zuffen · Posted: Fri Sep 07, 2001 4:26 am Post subject:

One other thing you could do. Plasti gauge the bearings on the rods and mains, to see if they really need replaced. I've only done one lower end and that was because the engine had low oil and spun a main bearing.

All the others looked great.

Its not alot of money but every penny saved can go to upgrades.

_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

Rick MacLaren · Guest

Actually, you could have a lot of your parts X rayed...

keith · Guest

can you access the mains without completely disassembling the engine? (I'm thinking of the 951 here, where you have to split the case...)

And yes, I'm going to boost it, ala HKS EVC (early series). I'm assuming I'll have some issues to contend with concerning the stock wastegate...

The HKS is to be coupled with the use of an intercooler, either a side-mount unit like the SAAB 900 unit, or front mount 951.

I want to stay as economical as possible (have VERY LITTLE in this project, including car, replacement engine, and controller), but I think a streetable, reliable 200+ hp should be achieveable with the better boost control and intercooling?

To get back on topic - just want to take care of the problem areas before I stuff the motor in there...

larso · Guest

I haven't checked my bearings in my 931 block yet, but I heard from a guy with a 924 that took his bearings out and they were down to the copper, also know a guy that has spun a bearing in his 931, i personally don't think they are bullet proof, the bare block itself is, but not the rings, bearings, pistons, seals, all the wear points are just as bad/worse as other cars. In other words, (most) Porsches and jettas burn oil, (most) hondas don't. Hondas are the one that have bullet proof blocks.

cs · Guest

most porsches are also built with more clearance than hondas. no one will accept a honda that uses oil. but once a honda does start using oil then it's pretty much dead. burning a little oil isn't a bad thing, most machinists will tell you it's better to be a little loose than a little tight.

Zuffen · Posted: Thu Sep 13, 2001 5:51 am Post subject:

also Honda's have a bad trait common with a 924 and that is the cam journals can wear out and cause low oil readings. Once the head is out of spec the motor is toast, cause you can't cheaply redo a honda or Porsche head. The Porsche would be easier to line bore and sleeve.

larso · Guest

burning oil isn't that bad of a thing you are right, but it makes me feel like I don't know how to take care of a car, people look at you and say, wow, there's another porsche hacker, doesnt know how to keep up his car.

It's just annoying to also diagnose an oil problem, if it is just the rings, if it is the turbo, the CV, the seats, there are so many oil burning problems.

Not sure about the tight clearances thing, wether thats a good thing or bad thing, because thicker oil means you lose power, and tighter clearances also make you lose power but you can run thinner oil.

Not sure about honda cams cuz i haven't had much experience, all i know is the rockers are even easier to adjust than the 924 valves and that rocker engines are harder to modify than a 924 cam since you have to get shorter valves so they don't break in a honda etc.,
About the strength of cams though and the bulletproof ness of a 924 cam:
A dude just bought a 924 cam from me, he sent me a picture of his old cam, I think you will laugh, here it is:

http://members6.clubphoto.com/l457220/495994/owner-c387.phtml

click on "924 cam lobe" it's after all my drum crap in my album

Zuffen · Posted: Fri Sep 14, 2001 3:24 am Post subject:

Lars
forward the pic to Vaughn so he can post it showing what happens when you don't change your oil and also letting the need for a valve adjust go on to long. One other possibilty in this is that the oil feed tube broke. I had a 79 engine which did just that. My cam is worse than that, the car still ran though, amazing.

_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

cs · Guest

the cam i took out of my 924 would make that one look like a joke. mine probably had a flat area twice the size of that one, but it was like that when i got it, not my fault. as far as the clearance thing goes, my brother is a machinist in the motorsports/prototype division of mahle. basically he makes the pistons for nascar, irl, indy, and anyone who wants to pay a lot of money for a set of custom made pistons. generally, the higher performance the piston, the more oil it's allowed to use. it's true that there is hp loss, but it's a small price to pay to ensure that the engine doesn't seize up from the heat expanding everything. of course, like everything else, everyone has their own theories.