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Discussion Starter · #1 · (Edited)
I'm at a standstill with my 72 GT right now! Would love to be able to pull out her heart and have her punched out to a 2.0, but beyond R&R of the head and timing chain ect...I'm not equiped to R&R the engine and tranny myself! :( I bought the car off this site in Houston and drove it all the way back home to CA. Since then I've done the brakes/includ. master cyl. new pacesetter header, shocks, weber 32/36 and got the linkage and auto tranny kickdown working. The PO must have replaced the radiator and water pump as they look new, so was the fuel pump (new) but they left off the spacer and it was leaking oil from the weep hole so I replaced it and tightened a few things up and oil consumption is almost nill!!! It idle well, no knocks and pings and can climb hills faster than the 1991 Dodge Dakota 3.9 I have. She has low 120-95 compression though all within allowable to each other according to the manual. It's almost like if it aint broke don't fix it!!! I think most off the compression loss is due to the head as the plugs show no signs of fowling and oil consumption nill. Problem is if I only do the head and cam I could develope leagage past the rings after icnreasing the pressure with new valves ect... I have to decide like this weekend to buy new standard flat top pistions with rings and pins for $295 off ebay ( seller had two sets and I was second highest bidder) to proceed with a freshen up approach or wait till she needs the rebuild and spend about $2,000 in parts and labor for a 2.0 complete rebuild. Also on a freshen up just replace the rod bearing??? And or the mains without removing the crank all of this done from under the car with the pan removed of course. The ebay piston seller has bearings as well...

Thanks in advance for your replies! You guys are the best!!! ;)

I got a answer from (God) Good ol Rally Bob and I respect his thoughts greatly after reading his, GT JIM and Otto's accomplishements and advice (wer'e talking hours of reading posts) a freshen up is ill advised!!! :( I just afraid to do the head alone!!!

Rick
 

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i was terrified to dig into the head my first time too. its not that bad. you will have a hell of a time finding a proper valve spring compressor though. i had to build my own from an 8" "C" clamp and cutting a notch into it. works like a charm and only cost 12 bucks for the clamp opposed to spending 100 from a catlogue. careful you may get addicted to head work and start porting like i did. since you are so close to me if you want to drop it by Id be glad to help you out and even do a little porting on it. we have a really good machine shop here too. had 2.0 valves and hardened seats put in for $322. and they are quick about it.
 

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Your freshen up plan is what the trucking business calls an "in-frame overhaul" because the engine is not removed from the chassis. I call it a "quick and dirty" and I hate them. On a truck engine at least we can pull the cylinder liners and replace them, on a car engine that is the equivalent of boring and honing, so at least the cylinders and pistons are good as new and the rings will work properly.
Whenever you open up an engine you find worse than you hoped for, at that point you have to decide to do a "half assed repair" and throw it back together, or get real and pull the engine and "fix it", realistically called a "rebuild". There is a huge difference between "fix" and "repair" and those of us in the business know it and have to explain this many times a day!
That's the only way you know you've got something that will run to your liking.
On a little Opel engine you don't have much room for error, one little important detail skipped or cheapened will cost you power and you'll find yourself being passed by Yugos.
Or you can always leave well enough alone and just drive it! When it really needs a new engine you'll know it!
 

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Discussion Starter · #4 ·
Thank You guys for your posts!

Wasp will have to get togather someday, maybe caravan to a meet would be nice! :D Any way what I was saying about just doing the head alone is the gained compression would probably make the tired lower end give blowby! Not to mentioned me having to look at those pitifull dished topped Horsepower robbing Emission controlled pistons before closing the casket lid after a head and cam rebuild!!! :eek: The Opel reminds me of my last year in high school and the gas pump wars, the Nox and smog pump ect....the end of the Muscle Car!!! :( Those were the days AMC Gremilin with a 401 C.U.
Z28 Camaro that'll smoke the tires almost a full block, or a 67 GTO with 2 duces (3) 2 barrels for anyone wondering)! It's hell too get old!

Just have to decide if I should buy the STD. Flat tops for $295 or Just spend the extra $100 and punch her out to a 2.0 with only aprox. 10 hp more, she could probably runs standard 93 mm flat tops with .030 oversize I'm guessing
giving me about 102 HP. better than the 65-68 maybe I producing now!!!

Cheers!
Rick
 

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Detritus Maximus
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Rick-

Do yourself a favor, if you have limited resources for pulling motors (meaning indoor space and equipment or money?) and are worried about the bottom end of the motor, find another block to rebuild, preferably an early high compression unit. Get it ready, buy a small folding hoist (about $200, cheaper if you shop around), and have everything ready. Since it sounds like you have no problem pulling the head and replacing with the motor in the car, I suggest you pull the head, then pull the block and trans as a unit (this can be done as opposed to trying to pull the entire engine out the top). This may be much easier than lifting the car and dragging the engine out from under it.

You could pull your head and have it done now, then re-pull it when the 'other' shortblock is ready. Or get the shortblock ready and swap it with your existing block while the head is in the shop. The problem here is if you go with bigger valves or cam, as that may require checking head/valve/piston clearances, which are much easier to do on an engine stand at the machine shop.

Even if you just want to do a freshen up, you can't do much about the cylinder walls with the crank in the block, no honing or polishing. I personally would not put new rings and pistons into old untouched cylinders. Especially $300 to $400 worth of pistons and rings. I might be willing to put new rings and some used flat tops in it.
 

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I have to agree with Opelbits on this one. Find a 69 or 70 block and do all the work to it first while still enjoying your "driver". After the rebuilt block is ready to be installed you could rent a lift if you don't want to buy one or if you don't have the storage space. You could easily have the swap done in a weekend and send the rental back, probably cost 50 bucks for a weekend.
 

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Detritus Maximus
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Watch out with rental lifts, usually they are pretty big monsters.
 
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