Packard Forum Index » V-8 (1955-56)

are they so heavy that they would cause problems at 5K rpm??? I don't really know. I'm guessing that about 6K rpm will top out a Packard V8 and 5k rpm sustained would top one out.

What is the alternative for an easy adjustment???? SBC type ball and stud is optimal for weight issues and alignmnet but alot of work to modify the Packard V8 for them.

As for "3 hands" to adjust just learn to do it with 2 hands by holding two wrenches in one hand kind'a like chop sticks and truning the end screw out with the other wrench in the other hand. Nearly always requires LONG THIN tappet wrenches.

The maximum RPM the Packard V8 will turn depends upon the camshaft, lifters, valves and springs used. The OEM engine will not reliably turn 5,000 RPMs. The valves are long and heavy, the springs are weak and the hydraulic lifters will pump up. Every manual transmission '56J I have ever torn down showed damage from at least one dropped valve.

With lighter valves, stronger valve springs, a good science roller camshaft, there is no reason a Packard V8 can't turn 8,000 RPMs. I'm building on one with these parts as we speak.

The late Steve Williams raced a stroker Packard V8 and told me he turned 7,500 RPMs. The camshaft he was using was so radical it would not idle below 1,800 RPMs.

As far as the GM ball-and-stud rocker arms, no serious racers use these any more. Today's GM racers spend big bucks with Jesel for shaft-mounted rocker arms. Packard and Studebaker got it right the first time.

When adjusting the pushrods, one hand is holding two wrenches, the second hand is turning the adjuster and the third hand is holding the feeler gauge.

thnx, jack vines

Quote:

This is one of the reasons why I chose flathead engines over the Packard V8. Can't drop a valve that has no place to go.

JV wrote: "Every manual transmission '56J I have ever torn down showed damage from at least one dropped valve."

Let me guess, the dropped valves seized in the guides?? Along with excessive guide clearence in the others that did not drop????

"Today's GM racers spend big bucks with Jesel for shaft-mounted rocker arms"

Probably because they are Aluminium???? I don't know what the Jesels are.

JV wrote "With lighter valves, stronger valve springs, a good science roller camshaft, there is no reason a Packard V8 can't turn 8,000 RPMs. I'm building on one with these parts as we speak."

Is this engine specifically for drag racing or for sustained high rpm operation over several hours???

1. Dropped valves were not siezed in the guides, but because the Packard V8 uses the longest, heaviest valve ever seen in a US OHV car engine. FWIW, the early big block Chevrolet 396" used long 3/8" diameter valves and was also plagued with dropping valves when run hard, and they were lighter than the Packard valves. The Packard valve springs were insufficiently strong to control the heavy valves and they floated when wound above 5,000 RPMs. The BBC hi-po 1965.5 396" V8s were good to 6,500 RPMs and then broke valves. With current valve spring technology and cam profiles, they are good to 8,000 today.
2. The race heads being of aluminum has nothing to do with needing shaft-mounted rocker arms. There are many aftermarket aluminum heads which still use the ball and stud. Modern 8,000 RPM racing engines need the stability and accuracy only a shaft-mounted rocker arm can provide. Ball-studs flex too much, even when a upper girdle is added. Jesel is the leading manufacturer of racing shaft mounted rocker arms for Chevrolets.
3. If circumstances ever align, I'd like to take the Packard to Bonneville, but if that doesn't happen, it will be streetable. AFAIK, the fastest Packard V8 ever timed was something like 145 MPH, so having the world's fastest wouldn't be too difficult.

Rich Fox has a Hilborn-injected 352" Packard V8 in a Vega. He is sorting it out and should easily exceed the 145 mark. He is using one of my NOS Iskenderian 505C cams reground by Deema Elgin, so I wish him good speed.

thnx, jack vines

The name Jack Vines keeps ringing a bell to me. There was a Jack Vines Raceing Team back in the 60's or early 70's ???

Or maybe it was HD aftermarket hi-perf parts manufacturer???

Since this thread has already been hijacked I don't see too much harm in continuing

Pushrods don't care on bit what engine they're in, all you need concern yourself with is length, diameter and ball shape. Weight or material is less a factor if you're not going racing.

Regarding valve springs, I'd be very interested to see if more modern bee hive springs could be installed in an attempt to address the problems inherent in the originals on these engines. For those who don't know, bee hives generally lack the self destructive harmonics and yet be run with lower pressures than a standard coil spring would require to eliminate bounce.

PackardV8 said "LLoyd. Did u see the so-called 56J engine that was on ebay recently????"
Are you sure you weren't referring to this engine?
cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll ... witem=&sspagename=STRK%3AMEWAX%3AIT

If so, I know the engine and the owner. That is a
Studebaker engine, not Packard.