Alright, finally tackling my 4.0 head swap.

[NoCoEagle]

I also already regasketed everything on the bottom end while the car was running (with help from member tougeagle), which is another reason why I wouldn't want to use the 4.0 block. Gaskets add up!

[doc65]

No, 258 pistons can't be used in a 4.0 block, they are smaller, you would have 0 compression and lots of noise as the pistons rattled up and down the bores when you spun the starter(it would not run) If you are staying carb'ed then you absolutely can run the manual fuel pump, though putting a generic electric pump and relay on the passenger side of the engine bay in the same general area as the manual pump is now would be easy & work fine(though most E-Pump vendors recommend closer to the tank as they push much better than they suck) I believe that the header you are referring to is a Rugged Ridge, and that is a very good question as to fitment, I have an APN header here taht I bought for my ZJ but haven't replaced yet that I've been thinking about using if it'll fit, my suspicion is that it won't without some serious massaging,  the one that seems to work closest without too much work is a 87-90 Renix style 4.0 exhaust often called a "Log" style exhaust

[eaglefreek]

I'll give you a $100 for the crank. I'll be in Denver tomorrow evening till Friday afternoon. Are you in Fort Collins?

[doc65]

Now there's a thought, wish I have thought of it...

[NoCoEagle]

I'm in the Fort Collins area, yes. I actually live up in Drake. Before I decide anything, though, any insight on my previous question of how the new crank would benefit me? Is it just dependent on the condition of the crank that's in there?

[eaglefreek]

I'm in the Fort Collins area, yes. I actually live up in Drake. Before I decide anything, though, any insight on my previous question of how the new crank would benefit me? Is it just dependent on the condition of the crank that's in there?

The new crank can benefit you by being able to rebuild another engine while still driving your Eagle with it's current engine. It sounds to me like someone was assembling the parts to build a stroker. 258 crank and rods and 4.0 block and pistons.
If that 4.0 block is truly a machined block and depending on casting number, I may be interested in it for another $100.

[captspillane]

I just purchased a brand new stainless steel exhaust manifold for 88 dollars on the evil bay. There was a bunch of the same one for sale. Its got the baffles where the stock ones usually crack. I was impressed with it and it turns out its identical to the one that my Spirit already had.

If you get that one, do not use the gasket it comes with!

When its time to put the head on I use two old 4.0 head bolts instead of buying the spacers. It works much better. I grind the hex head off and flip them upside down so that the 7/16 threads that used to be for accessories go into the block and the 1/2 threads stick up in the air. Slide the gasket down two bolts at opposite corners, align perfectly, then slide the head down the two modified bolts perfectly into place. It's a nightmare to do it any other way because you can't slide it without misaligning the gasket.

[NoCoEagle]

The casting # on the block is 53008405.

[eaglefreek]

The casting # on the block is 53008405.

That would be a 91-95 block.Let me know what you decide to do.

[NoCoEagle]

PM sent.

[carnuck]

I just purchased a brand new stainless steel exhaust manifold for 88 dollars on the evil bay. There was a bunch of the same one for sale. Its got the baffles where the stock ones usually crack. I was impressed with it and it turns out its identical to the one that my Spirit already had.

If you get that one, do not use the gasket it comes with!

When its time to put the head on I use two old 4.0 head bolts instead of buying the spacers. It works much better. I grind the hex head off and flip them upside down so that the 7/16 threads that used to be for accessories go into the block and the 1/2 threads stick up in the air. Slide the gasket down two bolts at opposite corners, align perfectly, then slide the head down the two modified bolts perfectly into place. It's a nightmare to do it any other way because you can't slide it without misaligning the gasket.

When I did the swap where the headbolts were wrong diameter, I did similar to what you suggested, but I re-threaded two of the bigger diameter bolts to the smaller thread and cut a screwdriver slot where the head was so I could back them out again.

[NoCoEagle]

Pretty sure my '88 head and the 4.0 head both use 1/2 inch head bolts.

[carnuck]

Some were 7/16"

[NoCoEagle]

They seem to have the same amount of play in the 4.0 cylinder head (tiny bit of wiggle) and the 4.2 head they came off of.