Additional Comparisons of US V8 Engines

AMC 327 XRV8 Race Parts Rambler V8 Specifications AMC Gremlin Rambler Marlin pictures Cutaway View of V8 Engines V8 Cutaways P2 XRV8 Gremlin Project AMC 327 XRV8 picture page

I finally found a cutaway view of the Chevrolet 'mouse' V8 engine, after over twelve years of searching the Internet, so I decided to add a second page of cutaway views.

'55 Chevrolet V8: 575 lbs. -head bolts and pressed in rocker studs penetrate water jacket, the two lifter galleries feed off the rear cam bearing groove along with the rear main: somewhat prioritized but not quite. It does appear that the 'short' style Chevy small block valve cover stamping may help oil the rocker tips by oil squirt deflection. Oil pump pickup tube needs a bolted tab to hold it on securely. Chevrolet did make internally balanced forged piston forged steel crank and rod versions of this engine in a variety of displacements which indeed makes the task of building one into a proper racing engine much easier if so equipped. Another design feature is seen by comparing total piston length to to total cylinder wall length of this engine to these other cut away veiws (note cylinder wall length is only 1/3rd longer than piston length) SBC's low deck/short stroke/big bore design was rather unique and it may be argued that this design peaked with '69 302 Z28 engine showing superb high rpm capability...

'66 290-401 AMC V8, 540 lbs. (generic weight) -Scan taken from '71 AMC Technical Service Manual, appears to be '68-'69 "AMX 390" having '66-'69 type concave floor rectangular outlet exhaust ports -quickly re-designed for '70 models to have better flowing convex floors; aka 'dog leg' heads.

Where 'time is money', this design adopted lower cost stamped steel rocker arms which, along with fewer drilled oil system passageways, increased speed of manufacturing and features simple wedge combustion chambers to meet new US Federal Emission Control Laws which basically outlawed the former AM Rambler V8 combustion chamber design. Lower cost/faster production speed cast nodular iron replaced more expensive forged steel crankshaft and connecting rods in the smaller 'bread and butter' versions of this engine

Notice the 'extra meat' around the crank gallery at oil pan flange for strength & rigidity compared to Chevy above.

Truth is, architecture of '66-'91 AMC V8 is near copy of Buick's '61 V8 design.

Cadillac also copied Buick's '61 oil-pump-in-the-aluminum-timing-chain-cover design when they revised their '53-'62 version of the '49 OHV V8 design in '63 for weight reduction. (revised 599 lb. Cad V8 then matched Rambler V8's 601 lb. rating)

The stock curved top AMC valve covers positively deflect oil squirts from the push rods to lube the rocker arm and valve stem tips.

It may be observed that all US automakers were doing a similar thing in the later half of the 1960s; all the 'bread and butter' engines were getting revised to have longer strokes, lower compression and simple 'wedge' style combustion chambers, a combination that is known to produce less toxic oxides of nitrogen exhaust emission content.

It's not that short stroke, big bore, high compression designs became outdated, rather it was the emission content of their exhaust that became illegal.

AMC published a paper bound book in '72 named "Performance American Style" which describes how to modify their inline sixes and vee eights in three sections for racing purposes, each section describes the general components needed to suit an expected rpm range.

Without exception, all 390 and 401 CID versions of this engine came with superior quality high strength forged steel connecting rods and crankshaft.

Although one AMC engineer was quoted in a magazine interview for saying "AMX 390"'s rotating parts were designed for 8000 rpm, none of these '66-'91 AM V8s came from the factory with internal balanced rotating assembly; they were all external balanced to reduce production cost and increase speed of assembly.






Old school Hi-Tech! Cord V8 mounted behind it's front wheel drive transmission, propeller type airplane engine style. Interesting valve train arrangement looks to be evolutionary missing link from flathead to overhead valve design architecture, but also to have 'V' cylinder layout with minimum width as inline eights were the norm at that time. (Interesting to check out 'Miller' inline 8 racing engine history... Duesenburg had double overhead cam inline 8 engine? Nash flathead inline 8 had 'twin spark' ignition; 16 spark plug distributor cap? Packard's 327 CID inline 8s weigh over 800 lbs?... 9 main bearing crank alone is like 150+ lbs?... but one of the smoothest running engines I've ever witnessed in person = truly can balance quarter on radiator cap!...)

Lycoming V8, for Cord

'32 Lycoming 392 cid V12 *the more I study spark engine design theory, the better this engine design begins to look. Crankshaft is designed for perfect balance, 'old' combustion chamber shape is 'new' diesel 'high tech'! Valve train appears to be extremely durable -note 'valve cover' -Ford 'Windsor' engines appear to have similar wrist pin oil spurt from con rod big end...

Pontiac V8; invented (?) 'modern' stamped steel rocker arms which could be manufactured by machines similar to high speed cookie cutters, instead of a much slower manufacturing process of casting/forging and machining 'conventional' shaft mounted rocker arm system... studs used to make solid lifter adjustment instead of dedicated pushrod adjusters etc = great innovation to enable higher speed manufacturing capacity... this pic shows Pontiac's 'early style' reverse flow cooling system...

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