New Eagle! Now I just have to get it started...

[eaglebeek]

Now you can not only do the 4.0L head swap, you can swap in the whole motor too!

I agree. I would not invest time and money in a 258 unless your intent is to keep your Eagle bone-stock.

You can also use your 258 crank in a 4.0 block to make a stroker of about 4.6 litres.

[djohnston89]

Wow, I wonder how that made it all the way into the intake? Somebody must have been very mean to this motor, it's only got about 90k on the clock and the generally excellent condition of the body and the interior seems to support that number.

Welp, I did consider this possibility when I bought it and figured worst case scenario I could throw a crate motor at it. I think I will probably go the 4.0 route route and stick a motorcraft carb on. Luckily since it's over 25, it's emissions exempt here so I can keep things as simple as possible. Is there any specific crate 4.0 that anyone would recommend, or does anyone know a good engine builder near Northern VA?

[djohnston89]

Photobucket keeps suggesting I make christmas cards out of the pictures I upload.
 I couldn't resist. 

[Amc1320]

Ouch, sorry about that, yep it's 4.0 time

There are lots of them available from rebuilders, very common. You could also find a good used one. I bought a used one with 80k miles on it pretty cheap and we put it in a gremlin my dad and I are working on. Used the intake off the 258 and motorcraft carb and HEI dist.

The hardest part was a fuel pump, had to add an electric one as 4.0's don't have a place for the mechanical one. Othe than that everything else bolted right into place

[1985amceagle]

Now you can not only do the 4.0L head swap, you can swap in the whole motor too!

I agree. I would not invest time and money in a 258 unless your intent is to keep your Eagle bone-stock.

You can also use your 258 crank in a 4.0 block to make a stroker of about 4.6 litres.

sorry to see about the state of your 258, I also am one that would not bother with a 258. the 4.0, even in renix form, seems to be a way better engine. I just haven't had one that was carbbed yet. they seem to have a lot more power than the 258, which makes a better jeep truck engine than an eagle engine. maybe a earlier 258 would perform better, but Ive only experienced the 1980 and later motors.

[carnuck]

The motors were choked with emission junk and the BBD was too small (one from a 318 is a better match) The Jeeps had lower gears which really helped because the O/D made up for it. I mean 2.37 gears? What were they smoking?

[Nightpath]

I'd put in a 4.0L and carb it with a good carb. Would be a good boost in performance, even though you don't get the nice fuel injection you don't have the headache of all the installation of fuel lines, pump and computer.

If you're really handy I'd stroke it. A bit more work and that beast will be amazing.

[Prafeston]

...even though you don't get the nice fuel injection you don't have the headache of all the installation of fuel lines, pump and computer.

Even if you carb a 4.0 you still have to install a low pressure pump in the fuel line somewhere. Preferrably closer to the tank.

[mudkicker715]

...even though you don't get the nice fuel injection you don't have the headache of all the installation of fuel lines, pump and computer.

Even if you carb a 4.0 you still have to install a low pressure pump in the fuel line somewhere. Preferrably closer to the tank.

there is a lot of mention about a fuel pump here. That is about the easiest piece of the puzzle. 

[djohnston89]

So i'm thinking I'm going to go with a Crate motor, either a factory 4.0 ($1600ish) or possibly the 4.7 ($2800ish)stroker that Summit offers from ATK . I know I'll need an electric fuel pump, that's not too big of a deal, and from what I understand I'll need to use a 4.0  header, which might require some modification/persuasion  to clear some Eagle specific 4WD stuff in the front. Is there anything else I need to worry about as far as fitment?

Tomorrow i'm going to get on the horn with a few shops around here and see what they charge to do the install (I never swapped an engine before and don't have an engine hoist, although i suppose i could buy or rent one) and that will largely determine how much I can spend on the motor without blowing my budget.

Also, is attaching that Stroker motor to the 27 year old stock automatic trans a recipe for disaster? Like, would I be asking for trouble putting that much power through it?

[mudkicker715]

Each tranny is different. That said my wifes stroker has handled it with an a998 also 3.08 geared.

[carnuck]

If the trans is a lockup, the stock converter won't take the power. The rear sprague could use upgrading (bolt in is best) as well as the billet/brazed converter neck. That was why I bought a 32RE (aka 999 electric shift/lockup) from a '99 Wrangler with 4.0L but I didn't get the flexplate with it and back then no-one had one for sale.

I robbed the gears, etc and put them in my previous Eagle's trans. Still have the case, valvebody, dipstick tube and part of a rebuild kit with clutchs for $50. Come Christmas it becomes scrap metal as I get paid extra for scrap right before Christmas and I don't want to rent another month's storage without income to cover it.