Need specs on Hesco Aluminum head

[5-90]

Most of the gain is probably from weight reduction going from iron to aluminum.

If it's tested for output on a dyno, weight is a moot point. There are advantages to an aluminum head, I just don't like mixing metals due to the differing coefficients of thermal expansion.

 

[Boostwerks.com]

Most of the gain is probably from weight reduction going from iron to aluminum.

Umm? :greensmok

 

[streetxj]

Umm? :greensmok

The butt dyno. :greensmok Weight reduction doesn't add hp, but helps with the acceleration and adds more to the "feel" of more power. That's what I meant by "gain" as in noticeable results. I apologize for the confusion. I might have exaggerated about the role of weight reduction playing a larger role than the flowing characteristics of the head. But, I'm pretty sure that it somehow plays a role in feeling the extra oomph during acceleration. Overall, for the price of a new hesco aluminum head, you could go with a nice stroker or boost setup. That is just my opinion.

 

[streetxj]

If it's tested for output on a dyno, weight is a moot point. There are advantages to an aluminum head, I just don't like mixing metals due to the differing coefficients of thermal expansion.

I understand. Not sure how it would work out with the jeep 4.0, but there are many engines that run a cast iron block with aluminum heads from factory. For example, Ford's 4.6, 5.4, newer 3.8's, etc.. A lot of the 5.0 mustang guys also like to run aluminum heads and don't have any problems that are caused by their cast iron block/aluminum head combo.

 

[O-Gauge Steamer]

FYI, going away from the single valve spring to double or tripple will reduce the bind as the wire diameter of the springs are smaller. Old school solution.

 

[Dr. Dyno]

there are many engines that run a cast iron block with aluminum heads from factory.

...don't have any problems that are caused by their cast iron block/aluminum head combo.

They don't have any problem until the engine overheats. Then the aluminum head can warp and crack because it expands at a faster rate than the block, and also blow the head gasket. The chances of head gasket failure during an engine overheat are much less when the block/head are of the same metal.