Help! I know i'm forgetting something!

[wolfclan]

So after tearing down my AMC 258 i6 / 4.2l and finding a cracked piston skirt, low comp on 3 cylinders and 2 burnt valves, I started on a major overhaul. I have just gotten the 4.0 head, added a header, Clifford intake, and Weber 38 carb. Without going crazy, what else do I need to do? Flow Kooler water pump? upgrade the stock motorcraft ignition? I'm in coastal SC, so I'm limted to fairly flat roads and trips to the hunt club for a little muddin'. Jeep also has a 5 speed manual tranny and 273 gears in an AMC20 diff, running on 31's with 0 lift (for now!)

I do not want to be stupid, just solid an reliable with this build. Any thoughts and comments are much appreciated.

 

[alpha6]

If you haven't considered it, I would go for the Nutter bypass and the Team Rush upgrade.

Here is one of the better links.
http://www.jeep-cj.com/forums/f2/teamrush-ignition-upgrade-11416/

 

[mtnwhlr]

 

[1986cj7]

So after tearing down my 258 and finding a cracked piston skirt, low comp on 3 cylinders and 2 burnt valves, I started on a major overhaul. I have just gotten the 4.0 head, added a header, Clifford intake, and Weber 38 carb. Without going crazy, what else do I need to do? Flow Kooler water pump? upgrade the stock motorcraft ignition? I'm in coastal SC, so I'm limted to fairly flat roads and trips to the hunt club for a little muddin'. Jeep also has a 5 speed manual tranny and 273 gears in an amc 20 diff, running on 31's with 0 lift (for now!)

I do not want to be stupid, just solid an reliable with this build. Any thoughts and comments are much appreciated.

Maybe a mild cam upgrade. As to which one someone with more experience in building motors needs to chime in.

 

[CJim7]

No need to go with a high dollar waterpump. You will install it and find out your 4.0/AMC 258 i6 / 4.2l runs hot anyways.
An ignition upgrade is almost a must...the stock junk is just that. I did a TFI upgrade on my inline 6 using all Ford parts and it is a huge difference. I didn the same TFI upgrade on my 401 with the same results. Best part is you are replacing stock parts with better stock parts.

Cam selection can be interesting. I used flat pistons on my build to bring up compression and used a 262 duration cam with higher lobe profile for my CFM needs. A 262 will be more then you need however...my build demanded it.

If you can get away with it in your area, I would highly recommend de-smogging it also.

 

[wolfclan]

No need to go with a high dollar waterpump. You will install it and find out your 4.0/4.2 runs hot anyways

Thanks. If its going to run hot anyways AND I currently don't have a fan shroud on the stock clutch/fan package, should I spend the $100 on a shroud or go for the dual electric fan upgrade?

 

[CJim7]

Thanks. If its going to run hot anyways AND I currently don't have a fan shroud on the stock clutch/fan package, should I spend the $100 on a shroud or go for the dual electric fan upgrade?

Some people like the electric fans over mechanical clutch fans....I've never used one. What I do know is if you use the mechanical fan, a shroud is a must.
The AMC 258 i6 / 4.2l tends to run a bit hotter with the 4.0 head upgrade. I've used Water Wetter with good success. I also louvered the hood to vacate heat.