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budget 258 rebuild

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purple72Gremlin View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Oct/28/2017 at 7:55am
Originally posted by DaemonForce DaemonForce wrote:


Originally posted by TheBirdman TheBirdman wrote:

I appreciate the tips, but please dont assume that Im
not up to the task just because Im new to your forum. That kind of
condescending smugness is what drives people away from cars as a
hobby.

It's not about the car. It is about fighting years of
bad engineering changes that hit performance in the worst ways possible.
It's about fighting years of poor service, moronic hack job repairs by
owners that had no idea what they were doing or they did and just wanted
to see this thing gone, creating a giant impossible mess for the next
guy. Either you are that guy willing to put the time, money and effort
into cleaning this up or you're an addition to the already painful
chore.
It's about effecting a permanent repair to a temporary
problem. I'm not questioning your skill with the Sunnen or what you're doing, I'm questioning what all has been done to the car that you have yet to discover. It's been over 4 years since my factory 258 blew up and I'm
just starting to weed through the cobweb of bad OEM wires and hackjobs
that warranted all new wires after building and swapping in a 4.7L L6. It's easier to get things running correctly when you don't have a mess.

I'm not saying you
can't make it better but you have a lot of work to do considering the
length of time this has been sitting. 20 Years of sitting is 20 years of
rotting seals, bad joints and worse for other vital components. This same situation was bad enough to my Javelin but multiple
people have tried to jump in and mess with it since they think it's a Mustang or Shelby. They didn't know what they were doing and now I'm out a 304 again. This is going to sit longer than the Eagle and that's been way too long already.

Originally posted by purple72Gremlin purple72Gremlin wrote:

I would definitely put a rear seal and timing
chain and gears in. But it's alot of work to remove the engine out of an
Eagle.

When you try to go cheap on something that has been
sitting long enough to automatically need a full refresh and you don't
go through it all, you're going to wake something that was holding
everything together or destroy something with an implemented hackjob
repair that you didn't know about. Surprise headaches aren't kind to
people on budgets or tight time frames and the Eagle's engine is one of
the worst to remove. So be aggressive about this and do it right the
first time.
Originally posted by AMXRWB AMXRWB wrote:

We have an Eagle that we fixed the worn out items on.Today it is the go to car for our family year round.We have owned it about 20 years and has outlasted many new cars our other family members have had. 

This guy gets it. Embarrassed
Oh I get it. But he said on a budget. So I try to help people. Not telling him goofy things like FMXs that fit AMC. Which isn't true. I stick with facts. If I don't know something I'll tell you that. I'm usually aggressive when it comes to engine rebuilding. But I've also rebuilt an engine cheaply, and the first day I drove it to kenosha....375 miles one way. Back in 2002.
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tomj View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote tomj Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2017 at 12:15am
most of the cost of rebuilds is in labor. the more you do the cheaper it gets. you can 'freshen' a motor for cheap, if nothings busted too badly. 

a full disassembly and cleaning, like all the way apart, pistons out, block boiled, parts inspected, new gaskets and seals, if you are double-lucky maybe just polish journals, new bearings (after very careful measurement, buy the tools if necessary, and plastigage, etc), timing chain, etc. 

but there's a serious tension between "budget" and half a century of wear. you could luck out, or not. i did just get a 195.6 ohv, '65, that's in wonderful condition, 0-under all around and everything's great. it happens. but most of the time there's a lot of wear.

i did one engine that had cylinder taper and out of round, not bad, but only honed it and reringed and compression stayed high and even and no oil consumption for 10 years. it was 40 pver when i started, same pistons, just got reringed.

my strategy is always quality over quantity. best oil and adhesives, best possbiel gaskets, and scrounge all my iron, hard parts off ebay, collect a bunch of stuff, sort out the best ones, swap and make fit.  cheapskate yankee all the way.

1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5
http://www.ramblerLore.com

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Post Options Post Options   Thanks (0) Thanks(0)   Quote DaemonForce Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2017 at 2:01am
Originally posted by tomj tomj wrote:

there's a serious tension between "budget" and half a century of wear. you could luck out, or not.

This is the part that I'm so concerned about because it's been the source of never ending professional embarrassment and a whole host of problems that prevents me from moving forward with anything in my life. When I encounter an antique engine that runs great but has been sitting around for years never being started or driven, don't expect a whole lot of life from those factory seals. In my case I look at doing a refresh whenever I acquire an AMC or Buick engine because they're prone to being left somewhere and forgotten. The only problem is my endless circus of FORD troubles that forces me to drop everything to give attention to that instead of doing what is almost always a badly needed 100% teardown, inspection and rebuild of these old engines. It's the same reason the Fords blow up on me every year and the lack of time/patience/$$$$$ is why they become scrap. AMC engines are cheap to build and cheaper to maintain than anything else puttering around besides Toyotas and those are becoming my new go-to for parts instead of the next yard Wagoneer. Everything else amounts to personal decision and build quality.

My plan of attack involves looking at the history for each generation of the engine on my build table and go to the last proven configuration OR force it to evolve with newer parts, creating an entirely different blueprint and final product. That last part is why I went from a 258 to a 285 and it's scary. I guess the bottom line is you get what you get. Ouch
1971 Javelin SST
American 304 2v | FMX | AM20-3.31

1983 American Limited
Jeep 4(.7)L S-MPFI | 1982 NWC T-5M (4.03/.76) | Dana30IFS/35-2.72
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Post Options Post Options   Thanks (0) Thanks(0)   Quote amcfool1 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2017 at 11:22am
well, for what its worth, I did an Eagle 258 in 015, and a Hornet 258 in 016, just motor alone, a full, and I mean FULL, rebuild for either was roughly $3000. This can be lowered if , unlike me, one stays away from premium parts, like, Harlan Sharp rollers, Cloyes doubles, etc. But, the Eagle, though basically the same engine as the Hornet, was EXPONENTIALLY more difficult to get out/back in/tuned., most of which was my own doing, 'cause I challenged myself, and brought it back to "stock", yes, including computer, feedback carb, and all eight sensors. Took roughly two years, for the Eagle, and a couple heads smarter than me, but, I am here to say, YES WE CAN! Eagles are the last frontier for us AMCers, so long story short, go for it, spend as much or as little as you can, but again, while its out, you want to do as much as you can, cause you don't want to pull that thing out EVER again! good luck, gz
george z
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Post Options Post Options   Thanks (0) Thanks(0)   Quote TheBirdman Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2017 at 11:28am
Thanks
I got the hoist this morning but I dont know if Ill get around to pulling the motor today, hung over me doesnt feel like it right now.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote amcfool1 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2017 at 11:37am
btw, sorry! for what it's worth, the Eagle, all done now, including it's new Freakride subframe connectors, StengelBros springs, and new NiCopp fuel/brake lines, runs up and down the road like new car, feeling solid as a piece of granite! Total expense, (ok, quick, my wife ain't looking!) a little over $20,000. Whew!
but, again, as close to a new 84 Eagle as one can come in 017! gz
if i ever get smart enough to post a picture, I will. The car, stock but new "Deep Night Blue" turns heads!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Greyhounds_AMX Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2017 at 1:12pm
I don't think it has been mentioned yet (or maybe I missed it), but you should really consider swapping in a 4.0L from a late model Jeep instead of repairing the 258.

Why?

1) It'll probably be cheaper. The cost for one piston, rings, gaskets, etc will be more than a long block at Pick N Pull ($170).
2) You'll get more power & torque from the 4.0L
3) If you wanted, you could use the factory reliable fuel injection setup from the 4.0L

There's writeups out there to help, here's one:


1968 AMX 390 w/T5
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Post Options Post Options   Thanks (0) Thanks(0)   Quote TheBirdman Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2017 at 4:35pm
It has been mentioned, and I am not wholly against the idea, but I couldnt find any good options for a 4.0 in my area. There is one 95 cherokee at the local u-pull yard, and entire engines are barely over $100, but I dont like the combination of not knowing anything about it, the time required to pull it, and the weather getting cold. There is one guy selling a 4.0 for $250 that has 200k miles on it, and I would probably have to rebuild it in another few years anyway. There are two guys selling 4.0s, but live an hour away and expect the buyer to pull the motor out of its jeep. In the end I decided it was just simpler and less hastle in the long run to get a full rebuild kit for the 258 for around $400. Part of it is that while ive done individual parts of rebuilds, Ive never done an entire one, and I enjoy sitting in my heated garage, getting greasy, and turning some wrenches, so this will provide me with both a few weeks of entertainment, and valuable experience. Additionally, I really dont care too much if it has 80 hp or 200. If i wanted to get somewhere fast, I would take my DD, and its not like there are any sheer faces of rock that need climbing in the upper midwest. The two primary uses for 4wd here is snow and mud.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote amcfool1 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2017 at 7:04pm
hey Mr. Birdman, I totally agree. Your 258 is bought and paid for right, and you KNOW it is a "bolt in", that much maligned phrase, since you can "bolt out!" What once was, can be again, right? If you have read my above comments, you can see that I just did a basically "no expense spared" restification on an Eagle. Yes I could have afforded to go the 4.0 route, but I chose not to. again, simply cause the 84 258 was in there, bought and paid for, and still (barely) running. btw, I paid $300. for this car seven years ago. A stock 4.0 is 190-205hp, stock 84 258 is about 120hp, maybe less, depending on whose counting. 
But, I tried to do things correctly, did my research, read LOTS of opinions, 4.0 head? Mr Farnas favourite upgrade, decided not to, just didn't like the idea of a home remedy for cooling jacket leaks. My 258 head is in, but with SBC 1.84/1.5 valves and positive seals, Harlan Sharp Roller rockers, and Comp Cams one piece pushrods, as well a a Comp cam/lifters. I have not had this on a dyno, but my engine builder, who is an old school honourable gentleman, said he crunched some numbers, and this engine should be good for about .8 to.9 hp/per cid. At +.030, about 262 cid, this motor should have about 215-235 hp, available down low. So, not having a 4.0 doesn't bother me in the least. I will say this, took over a year to tune this thing, but now, though it will never be a 401 match, this Eagle is FAST, even with stock 2.35 gearing, in town you are over 50mph before you know it! On the interstate, easy cruise at 70, about 2200 rpm, thing ain't even working hard.
So, the moral of this story is: 4.0s are great, But, keep your 258! good luck, gz
george z
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Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2017 at 7:36pm
A properly rebuilt 258 is NO SLOUCH. Just ask all the rock-crawling Jeep people. I've owned my share of them - including in a 77 AMX I drove all over the country (LITERALLY, Pike's Peak, Denver, AZ, a crazy range of weather or climate and elevations and it performed great)

PS - the 4.0 route will NOT be cheaper if you are comparing apples to apples. The parts to do the same sort of rebuild would basically be the same. PLUS - depending on your car, there are some little odds and ends that you have to do beyond just dropping it in. I went the 4.0 route because, well, that's me, who I am. The challenge, the fun, etc. My car is also beyond basic repair....... it's a no-holds-barred, find as many NOS parts as you can (including NOS ASH RECEIVER) and it will never be finished to my satisfaction. Ever. I added power locks and windows, added relays for those items totally revamping the factory switch wiring, ran many of the AMC electrical items through the Jeep PDC and relays, found a NOS transfer case, and more. 
Yeah, I went 4.0 but I'm a big fan of the 258. With a few tweaks a 258 can be even BETTER than good. 



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