BuckeyeBullet

I'm sure this has been asked before but I wasn't able to find anything quickly in the search. Anyway I have an '01 XJ that is new to me and I'm doing a mild build on the motor. I'm interested in opinions on hypereutectic vs cast pistons for the 4.0.

The engine is going to be bored, not sure how much yet but probably no more than .030". It will have a Crane 258 cam that's a little better than stock, and intake/header but nothing too fancy. I intend to use the Jeep as a daily driver with some weekend trail fun, and I might haul a ~450lb motorcycle from time to time. Only planning a 3" lift on 31s to keep it simple. Thanks

Bustedback

www.summitracing.com has a lot of pistons to choose from, they even have Keith Black (Silvolite) pistons for the 4.0.

BuckeyeBullet

I know where I'm buying my pistons from, but...would you recommend hypereutectics or cast?

Bustedback

Cast are noisy and expensive, I would go with hypereutectic. Just make sure the ring gap is correct when running hyp pistons.

mdnov

Don't you mean forged are noisy and expensive? Cast are stock aren't they?

Jeepjunky

personally i like J&E, and Sealed Power. i have also heard that a company called Bulltear are pretty good

mdnov

The Sealed Power are good. I believe they used to be TRW brand.

BuckeyeBullet

I'd agree there, that's why I wasn't considering forged for this build. I run TRW forged pistons in my '65 Dodge and they aren't too noisy but I'd still rather not have them in a daily ride. The stock pistons that came out of my XJ sure looked cast. My machinist also said cast were best for my application.

Bustedback

Yeah, you're right, I had a brain fart.

Outlaw Star

Sealed power are Federal Mogul brand. The same company that makes Fel-Pro.