1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

What to do, what to do.....

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Old 03-11-06 | 06:45 AM
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Question What to do, what to do.....

Okay, here's the deal. The motor in my '85 GS is just a few miles away from hitting the 200,000 mile mark. It still runs great, but I imagine that the compression is probably down a bit and with that kind of mileage who knows what other issues may be lurking around the next corner. The rear end is pretty loose as well, and the gears are whining pretty loudly so that's about worn out. The tranny has no issues, and the clutch is still strong.

Now, I also have a complete drivetrain from a '83 (GS I think). It reportedly has just a hair over 100K on it (no way to confirm though). I'm in the process of cleaning up the whole drivetrain right now (will post some pics later). The engine seems to have good compression when turning it over, but I have no other clue as to what kind of shape it is in. The manifolds are off, and it has all of its apex seals. That's about all I know about it. Engine and tranny have not been separated.

So, here's the question: Should I just swap this in to my 7 next week, and later rebuild the high mile motor thats in it now? Or should I rebuild the one sitting in my garage and keep using the old motor for now? I figure its a gamble either way (the motor I put in might turn out to have issues, or my old motor might give up the ghost while the new one is torn apart).

I'm tempted to just throw the entire drivetrain in and try my luck. But on the other hand, what would it take to do a street port on the new motor before I put it in? What parts would be needed and what kind of money would I be looking at? I can't afford to dump much into her at the time, so cheap is what I'm after.

Thanks for your input!
Old 03-11-06 | 10:20 AM
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Here are some shots of the drivetrain, not that you can see a whole lot.... Give me your thoughts on my situation. Thanks!
Attached Thumbnails What to do, what to do.....-cimg3206.jpg   What to do, what to do.....-cimg3207.jpg   What to do, what to do.....-cimg3208.jpg   What to do, what to do.....-cimg3209.jpg   What to do, what to do.....-cimg3210.jpg  

Old 03-11-06 | 11:58 AM
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Can't really advise you about which engine would be better for now, or even a better canidate for a rebuild. However, to answer the question about street porting the spare engine prior to installing, that will require a full teardown. Might as well rebuild it while it's apart. Porting is done from the inside.
Old 03-11-06 | 12:47 PM
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Rebuild the one with less miles, and premix on the other one (leave the OMP intact, but premix)... that way you're SURE the one in the car has enough lubrication and won't just blow a seal on you. You know that one works, so drive on it. The other one might not even run, you could install it and have to switch back. Too many hours of hassle for nothing.

Just be easy on your car until you get the rebuild done on the new one.

Jon
Old 03-11-06 | 04:55 PM
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I'm with Jon on this one. Port and rebuild the lower mileage motor. The housings on the 200k motor are probably very thin in the chrome, and a good chance the irons will need surfaced, then you would be pulling the newer motor out for parts to rebuild with and have the car down for a while.

Who knows, your 200k may engine may be good for another 50k.
Old 03-11-06 | 05:09 PM
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yeah leave the motor in the car in the car. rebuild the other one. replace the diff though, makes a huge difference
Old 03-11-06 | 05:11 PM
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Yeah, you guys are probably right. I've got the motor stripped right down to the block pretty much anyway. What am I looking at for a cheap rebuild kit, just enough to get me down into the porting area (assuming that I don't find parts that need to be replaced)? I know there will probably be some parts that can't be skimped on...

Damn, maybe a 1/2 bridgeport? Hehe, now I'm getting greedy. But I really want that turbo too.....yummy...

So I'll get ready to take a second mortgage out to finance my rebuild...
Old 03-11-06 | 05:20 PM
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put a TII motor in it.
Old 03-11-06 | 05:31 PM
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Agreed with Vipernicus and the other guys, just rebuild the engine while its out. Makes more sense than swapping them out and rebuilding the 200,000 mile engine when you know for a fact its running.
Old 03-12-06 | 01:44 AM
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conserve resources

Why not fix the rear end and baby the engine in the car untill you have the $ to do the full buildup?
If you are thinking turbo you may not want radical port timing.
A 13BT would be nice!
Old 03-12-06 | 05:11 AM
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That's a good point Wecycle. What would be the optimal porting if I planned to go turbo later on?

I suppose swapping out the rearend and driveshaft wouldn't be too big of a job. I need to fix a gas leak at the filler neck too, while I'm under there.

I also have the full bushing pack for the front end along with tie rod ends etc. I just can't wait to get the engine out so i can finish up my engine bay. If it ain't needed, then its coming out of there! lol.

One more question for you; isn't there a front cover and maybe a water pump that you can get that is alloy? Maybe something made for a 2nd gen or something? I think I remember reading about it somewhere, but can't find it now. Thanks for the input!
Old 03-12-06 | 05:26 AM
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hey i still want to get those 500 wt lights kentetsu
Old 03-12-06 | 05:31 AM
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i think the 2nd gen water pump is direct bolt on? that is aluminum.

as for the car. do whatever fits ya, i would rebuilt and SP one of them and keep the best shell. its in the end all up to you, so start thinkin'
Old 03-12-06 | 06:41 PM
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Alright, so is the Haynes manual good enough to cover a rebuild or should I fork out the $$$ for one of the videos? Time to start researching I guess. Now that the decision has been made to rebuild the new one, I can't wait to crack it open and see how it ticks. lol.

Man, my wife would kill me if she had any idea how much money I plan on putting into this car over the next couple of years. lmao.
Old 03-12-06 | 07:17 PM
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The haynes manual is preaty good for dismantaling.. not sure about the buildup. You may want to get both, that way should anything else show up in other parts of the car your good. The video is just better.. you see what you have to do and theres no second quessing a sentance in the manual.

my 2 rusted pennies
Old 03-12-06 | 07:45 PM
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kentetsu, you buffed out the transmisssion and the transaxle. looks very sharp
Old 03-12-06 | 09:09 PM
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Originally Posted by d0ntdreamit
kentetsu, you buffed out the transmisssion and the transaxle. looks very sharp
Thanks man. All I did was spray it down with some P.B. Blaster (see can in background, lol) and hit it with a wire brush on my angle grinder. This was a lot easier than hand cleaning it, and it did shine up pretty nice. Not that anyone will ever see it once installed.
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