Frequently Asked Questions

Why do you recommend aluminum heads even for engines destined to appear "Stock"?

Aluminum heads offer several advantages. Besides being more robust by design, the obvious one is weight reduction. Alloy heads also offer improved port flow, seats compatible with unleaded fuel, more resistant to detonation, and easily repairable, when compared to cast iron. When painted, they retain the "Stock" look.

What is the maximum compression to run on pump gas?

This is a question that nobody agrees on, as it can vary greatly due to cam selection. We rarely go over 10-1, even with aluminum heads. Unlike some small combustion chamber designs, hemi's have little quench at low compression. If the engine is efficiently filling the cylinders, a small camshaft can cause detonation, even at low compression ratios. We build many under 10-1 compression street engines that exceed 700HP. Too much compression for the octane of the fuel will be more detrimental to engine performance than compression that is slightly low. Note: higher altitude engines can use slightly more compression.

What intake should I use on the street?

We still recommend the cross-ram for many of our pro-street engines, and the Barton dominator intake for single four barrel applications. Another option now available is the new STAGE V inline single plane. It can use dual Holleys or Carters, and allows the use of factory breathers/shakers etc. (modification of baseplate required)or use a new FHO stamped steel baseplate. This manifold can be used for upgraded performance with it's much improved cylinder to cylinder fuel distribution or when the factory street hemi manifold is unavailable.

What are the advantages of the new STAGE V replacement aluminum heads?

Unlike their race heads, these heads come with stock location, but higher flowing ports, that require little machining. Compared to the Chrysler heads, they are far superior with integral spark plug tube seals, bronze alloy valve guides, better flowing ports, the ability to handle 2.30 intake valves and are made with higher grade aluminum which does not suffer from porosity or leakage. They have replaced the Chrysler head on all our engine packages.

Why do you recommend the STAGE V roller rockers for pro-street and race engines?

With the higher installed spring heights and longer valves often used with these roller cam equiped engines, rocker geometry is often greatly improved with the longer reaching tips available from STAGE V. During engine pre-assembly, valve tip wear pattern can be determined and rocker tip length adjusted if necessary for perfect geometry. The end result is reduced tip and guide wear.

** NOTE: Our NEW Titanium Roller Rockers offer all the above advantages plus much lighter weight and improved oiling.**

What are the advantages of purchasing a FHO crate engine over the Chrysler equivalent?

Not only can we tailor the crate engine package to fit your requirements, every component installed is the latest in design, not rehashed 60's technology. Our basic restoration engine package includes better heads, connecting rods, pistons and pins, valve-train components, (including roller rockers) and blueprinted engine assembly. All engines are delivered dyno tested with specification and parts lists. Pictures of assembly included. Thousands of dollars in improvements are done for the same cost of buying a lessor hemi engine elsewhere. Note: See parts and build lists.

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