High performance 4.0 or 4.2 aluminum head is available.

[Stumpalump]

Eldelbrock has come out with an aluminum head. Flows better and weighs a lot less. http://www.edelbrock.com/automotive/mc/cylinder-heads/jeep.shtml
Order from Jegs bare or built or just drool:Wow1:

http://www.jegs.com/p/Edelbrock/Ede...ormer-Aluminum-Cylinder-Head/3170486/10002/-1

 

[mr2kxj]

That's pretty cool! I had to swap a head on my old '01 XJ back in '08. Wish this had been available at the time.

 

[Mitch502]

I've been waiting for these to come out. I read about them about a year ago, and have been waiting since just to hear if they are as good as everyone says they will be.

 

[jk_surgeonfish]

So...what kind of performance would one get with this on a stock motor?

 

[DucRyder]

...or with headers, Cold air intake and a Bank's tuner:drool:

 

[shortbus4x4]

It would make some nice man cave art too.

 

[F40]

performance increase aside, I'm wondering if it'll keep that lump of cast iron cooler.

 

[Jurfie]

So...what kind of performance would one get with this on a stock motor?

 

[Mitch502]

View attachment 282025

What is this over stock?

 

[Jurfie]

1987-90: 177 hp (132 kW; 179 PS) at 4500 rpm and 224 lb·ft (304 N·m) at 2500 rpm
1991-95: 190 hp (142 kW; 193 PS) at 4750 rpm and 225 lb·ft (305 N·m) at 4000 rpm
1996-01: 190 hp (142 kW; 193 PS) at 4600 rpm and 225 lb·ft (305 N·m) at 3000 rpm
2001-06: 190 hp (142 kW; 193 PS) at 4600 rpm and 235 lb·ft (319 N·m) at 3200 rpm

 

[Mitch502]

~25hp and ~30ft. lb. torque. not too shabby.

 

[aluke0510]

Depending where you live and how strict they are with emissions you may have to wait a bit longer; they are still pending emissions legal status. Back when Hesco still sold theirs it was something like a 30lbs weight drop as well. A lot of people didn't get the full increase out of Hesco's though; possibly partly because of other improvements to the engine they had already made.

 

[Shoeman]

I'm always skeptical when companies claim big number gains over stock. But I took a quick look around for stock 4L dyno charts and from what I could see, this new head does not really penalize you anywhere in the power curve. It's can be relatively easy to boost peak HP or torque at a given rpm but the trade off is often a decrease somewhere else, often in a place you really don't want it to drop. But this chart when compared to factory 2000's and a few newer actually makes more torque everywhere and has no significant dips in the curve. Impressive. It gives really noticeable gains over some of the earlier years, but there would probably be other parts that need changing to realize the full potential of this head on those motors. Nice flat torque curves that start early and hold steady are where it's at in my experience. Turn that tire and grunt over things and up hills.