Pile of Parts - What Would You Do?
Posted: April 8th, 2023, 6:30 pm
Hey Everyone! I'm working on a 1988 AMC Eagle with the 4.2 and automatic. I am wondering what ya'll would do with the following available to you (with the caveat that I've already spent thousands on the following parts/components+ and would like to spend as little more money and time as possible):
1. 1988 AMC Eagle 4.2 complete engine/car. The block is cracked in 2 places and head is slightly warped. My machinist thinks the crank could use a slight grind but looks good otherwise. No spun bearings and the engine ran so I think the connecting rods are ok. I've purchased everything for a cooling system rebuild and the radiator has been re-cored.
2. 1998 Wrangler 4.0 complete engine with mpfi/harness/ecu. "Ran well" when pulled. Low compression on cylinder #1, no change with oil in cylinder. So likely a blown head gasket and/or (hopefully not) a cracked head. Removing the head for inspection tomorrow.
3. Comp Cams mild/torque cam (232-4) 800-4800 rpm, Comp lifters, pushrods, std valve springs, rockers, Comp timing set. Purchased for the 4.2 but seemingly all compatible with the 4.0.
4. Aces brand "Deuces Wild" throttle body EFI with spark-controlled distributor, fuel pump/regulator/lines (350hp capable with dual 100lb/hr injectors).I bought this for the 4.2 before I knew it had a cracked block.
Originally I just wanted to get the Eagle running and use as a daily driver... well sadly, cans of worms were opened. But I find myself having most of the parts for a stroker build for potentially little more money.
A. My machinist is months behind on work. Is it at all reasonable for me to think I might be able to avoid all machining with a 4.5 build? i.e. drill hone cylinders, new std-size crank bearings, fine sandpaper on 4.2 crank (there are no gouges), new std-size rod bearings, reuse the 4.2 rods, swap to 4.0 std pistons without a special press (?), change to aftermarket cam without changing the cam bearings (or leave the 4.0 cam in place?), new piston rings, rear and front oil seals? I think most of you will tell me to just have the machine work done to avoid having to do it all again in 20k miles!
B. In the likely event that I do have all the appropriate machine work done, seems like a 4.6 build would be better and less stressful on the engine & starter (lower compression) as well as my wallet (87-89 octane). Except those custom $700 pistons! Anyone have a source for cheaper pistons that would work with the 4.2 crank, 4.0 rods combo?
C. Is the factory Jeep mpfi/ignition system going to be a lot better than the aftermarket TBI I bought (whether stroker/cammed or unmodified 4.0)? I really am not looking forward to the prospect of adapting the 4.0 mpfi harness to the Eagle's electrical system and am more interested in simplicity and reliability than tons of power. My old Chevy 350 with TBI was one of the most reliable engines I've owned...
I apologize for the length and thank you for your insights.
1. 1988 AMC Eagle 4.2 complete engine/car. The block is cracked in 2 places and head is slightly warped. My machinist thinks the crank could use a slight grind but looks good otherwise. No spun bearings and the engine ran so I think the connecting rods are ok. I've purchased everything for a cooling system rebuild and the radiator has been re-cored.
2. 1998 Wrangler 4.0 complete engine with mpfi/harness/ecu. "Ran well" when pulled. Low compression on cylinder #1, no change with oil in cylinder. So likely a blown head gasket and/or (hopefully not) a cracked head. Removing the head for inspection tomorrow.
3. Comp Cams mild/torque cam (232-4) 800-4800 rpm, Comp lifters, pushrods, std valve springs, rockers, Comp timing set. Purchased for the 4.2 but seemingly all compatible with the 4.0.
4. Aces brand "Deuces Wild" throttle body EFI with spark-controlled distributor, fuel pump/regulator/lines (350hp capable with dual 100lb/hr injectors).I bought this for the 4.2 before I knew it had a cracked block.
Originally I just wanted to get the Eagle running and use as a daily driver... well sadly, cans of worms were opened. But I find myself having most of the parts for a stroker build for potentially little more money.
A. My machinist is months behind on work. Is it at all reasonable for me to think I might be able to avoid all machining with a 4.5 build? i.e. drill hone cylinders, new std-size crank bearings, fine sandpaper on 4.2 crank (there are no gouges), new std-size rod bearings, reuse the 4.2 rods, swap to 4.0 std pistons without a special press (?), change to aftermarket cam without changing the cam bearings (or leave the 4.0 cam in place?), new piston rings, rear and front oil seals? I think most of you will tell me to just have the machine work done to avoid having to do it all again in 20k miles!
B. In the likely event that I do have all the appropriate machine work done, seems like a 4.6 build would be better and less stressful on the engine & starter (lower compression) as well as my wallet (87-89 octane). Except those custom $700 pistons! Anyone have a source for cheaper pistons that would work with the 4.2 crank, 4.0 rods combo?
C. Is the factory Jeep mpfi/ignition system going to be a lot better than the aftermarket TBI I bought (whether stroker/cammed or unmodified 4.0)? I really am not looking forward to the prospect of adapting the 4.0 mpfi harness to the Eagle's electrical system and am more interested in simplicity and reliability than tons of power. My old Chevy 350 with TBI was one of the most reliable engines I've owned...
I apologize for the length and thank you for your insights.