4.0 rebild

im rebilding my old 4.0 out of my 2000 XJ and i want to put like a stage 1 cam in with roler rockers to get some more power and i was thinking of putting a aluminum head or should i just get a thicker cast head.

The answer depends on the amount of money you want to spend.

If it was me I would do the comp cam extreme 4x4 cam kit.

If your head is good ,I would reuse it.. Don't know about alum. heads for the 4.0 . I'am sure they are expensive.

Just my two cents

Nick

jimbow912 said:

im rebilding my old 4.0 out of my 2000 XJ and i want to put like a stage 1 cam in with roler rockers to get some more power and i was thinking of putting a aluminum head or should i just get a thicker cast head.

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old 4.0, 2000? How many miles are on it. I got a 2000 with almost 110k and it runs just like when I brought it home the first day. It does get fresh Rotella every 3k, that keeps her happy.

I would consider the comp cam, or there are a few good crane cams out there depending on what you want out of it. For the head, I would grab an older casting head from the J/y and then have a shop touch up the ports, re-valve it with bigger valves and the correct springs for whatever cam you choose, and then just clean it really well. Paint it and throw it on. Roller rockers are good, but not very necessary unless you don't have anywhere else to spend the extra $350 in coin, with just the cam they will not make much of a difference if any, more of a high RPM helper than the ranges where a 4.0 runs. I would consider dropping in a 4.2 crank and rods while you are rebuilding. Coupled with the head work and cam that would make a world of difference compared to just a cam.

This is all based on you not saying exactly what you meant by a rebuild. I assumed whole hog tear down because that is more fun. I would also consider proof reading and a spell checker if I were you.

all depends on what you want the rig to run like, so, I would advise getting a quality valve job and a custom cam. There are professionals out there that design cams... well worth every penny.