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Experience with a Rebuilt 258

Experience with a Rebuilt 258
I think that upgrading your rig to the used 4.0 (complete with F.I./ECM/etc.) is about as much work (if not more) as just installing the used 4.0 and dropping carburetion on it. And remember, the weekend peeps that help you cut 'n splice may not be available when you break something.

IMHO, F.I. is superior WHEN IT IS WORKING...carbs are easier to field repair and keep limping along. What I don't like about a non-factory F.I. installation are the gremlins that invariably come with all electrronic projects.

For me, carbs are easier to diagnose and tune...but then I'm old school. What is best for you long-term may or may not be like me. :)
 
For me, carbs are easier to diagnose and tune...but then I'm old school. What is best for you long-term may or may not be like me. :)

You know, I'm glad you brought that up because I had the same thoughts. I was hoping I could cast them aside for this and hopefully reap some benefit but I'm not confident. I really don't dig vehicle wiring so the O2, MAP Sensor and the CPS send chills down my spine and it's one of the reasons I was avoiding FI and newer diesel engine swaps.

I was just comparing the two engines and saw that the 4.0 has less low end torque which is what I like about the AMC 258 i6 / 4.2l . I would like more pulling power up some of these long hills not necessarily more get up and go. Every time I try to veer away, the AMC 258 i6 / 4.2l draws me back.
 
I was just comparing the two engines and saw that the 4.0 has less low end torque which is what I like about the AMC 258 i6 / 4.2l . I would like more pulling power up some of these long hills not necessarily more get up and go. Every time I try to veer away, the AMC 258 i6 / 4.2l draws me back.

Two ways to solve this, and I've done both:

AMC 258 i6 / 4.2l w/ 4.0 head OR Stroker 4.0 w/ AMC 258 i6 / 4.2l crank.

I've run each with the same camshaft (CompCam 252H) and I can't tell you the difference...but I think the stroker has a wee bit more bottom to it. Either one creates a worthy ride, IMHO. I would build either one again. My decision would be made by the available parts. :cool:
 
Anyone have experience with an RV Cam?

I'm using the low end anyways since that is where all my power is. Was hoping this would give an even bigger boost in that spectrum.
 
I just so happened to have replaced my blown AMC 258 i6 / 4.2l with a rebuilt AMC 258 i6 / 4.2l that has an RV cam last weekend. I'm still in the break in period, so I don't have a lot to offer you. I can tell you that I like the way it is performing and it sounds really cool with headers and a glasspack. I think I'll be very happy with it. I have a 2 barrel weber carb running 33" tires and a T-176 4 speed. My 3.07 gears could be a little shorter, but it allows me to travel down the freeway when necessary without redlining.

Personally, I like to drive down the back roads in 1st and 2nd gear just listening to the exhaust. It's rather soothing.
 
Good to know. I'm looking forward to it.

Spoke with several machine shops to feel them out. All of them said they now install RV Cams as standard practice. Said will give me better low end and able to pull up long hills better. They said with my setup it may also help my MPGs but it definitely won't hurt it. Read that it changes the engine sound as well.
 

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