WaynesWorld

In my research, there are a couple different 394's. Which one do I have?

How do I identify the high compression 394 to the low compression one?

What should the correct color for my motor and air cleaner be? Is there a guide that has this info?

I think I remember seeing three different horsepower ratings for a 1964 394 in a ninety-eight, which one do I have? It is 4bbl.

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Run to Rund

Hopefully someone else has the 64 service manual. Based on my 62 manual, green engines were 88 low comp (except export models), red were high compression. 98 had only high compression 4 bbl engines.

rocketraider

Assuming it's the original engine, a SkyRocket is the 330 horsepower high compression version of 394. There should be a curved "Ultra High Compression" decal on the front of aircleaner housing; looks like yours is AWOL.

It could have optionally been equipped with the 345 horsepower Starfire engine. Those engines when factory installed will always have dual exhaust.

You can also look on the left head, just below the valve cover and above the center exhaust ports. The engine ID number is there. An H prefix indicates a 2-barrel engine. A J indicates 4-barrel.

No suffix indicates standard 10.25 CR. An L indicates an 8.75 CR engine. An S is 10.5 CR Starfire engine.

As an example J001001 would mean a 10.25 CR SkyRocket 4-barrel engine. H001001 is a 10.25 2-barrel Rocket engine. H001001L is a low compression 2-barrel. Those were green and usually found only in Dynamic 88s. J001001S is a Starfire engine.

stan 65 cutlass

on top of the bellhousing is a number and the high performance ones had a 1/8 beside it. if memory serves me correctly

WaynesWorld

Thanks for the input.

Air Cleaners- I've seen pics of silver and black.... which is correct for a 10.25 CR SkyRocket 4-barrel engine?

rocketraider

All 1964 4-barrel aircleaners are silver.

59-59-59

Your probably thinking the number of 4 1/8 ,which means nothing more than the standard bore size that figures out to a 394.

stan 65 cutlass

check the tech section, block id 1949-1964
says red block hi compression, green low comp. if original paint
1964 394 #585786 this specific casting # seen on ultra high comp engines, the number 4 1/8 follows casting number. i knew my memory wasnt failing

OLDZGUY

On a 394 Engine the Unit Number is Stamped on the LEFT Cylinder Head just below Valve Cover center bolt. By using this Number, the prefix & Suffix Letter will tell which 394 you have.

Red Engine: 88 / prefix H suffix – / 2BC, 280HP, 10.25:1 CR

Green Engine: 88 / prefix H suffix E / EXPORT 2BC, 8.3:1 CR

Green Engine: 88 / prefix H suffix L / Domestic 2BC, 260HP 8.75:1 CR

Red Engine: 88, S88 & 98 / prefix J suffix – / 4BC, 330HP 10.25:1 CR

Green Engine: S88 & 98 / prefix J suffix E / 4BC, EXPORT 4BC 8.3:1 CR

Red Engine: SF & 98 / prefix J suffix S / 4BC, 345HP 10.5:1 CR