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and if one was to get custom made pistons done......wonder what it would take to test the rumored max 500 cubic inch that Packard was supposed to beable to do with this block? course that may not work too well with my TU trans LOL!

Overboring for cylinder wear isn't really a modification, it's just maintenance.

Here's a little formula from Steve (58L8134) over on the Modifications board for figuring cid based on bore and stroke.

Cubic Inch Displacement= Bore (squared) X Stroke X 0.7854 X Number of Cylinders.

The Packard 352 has a 4" bore and 3.5" stroke, so .030 over would yield about 357 ci. Pretty cool number.
.020 gives you a 355.

As far as keeping it "stock," your current .012" of wear doesn't work out to a perfect 352 any more either. But by any other displacement, it's still a "352" Packard engine, because that's how it started life.

Now a radical overbore or stroking the crank, then you're really talking a "modified" non-stock engine.

Quote:

The Ross piston for Packard is machined from a basic forging for SBC. That's what most of the high performance aftermarket suppliers do. The pistons from Egge are hand cast one at a time and do not have the internal steel expansion control rings like the original Packard pistons.

As far as the size difference, forged aluminum is much stronger than cast aluminum, hence a thinner skirt on a forged piston is just as strong as a thicker skirt on a cast piston. The Ross pistons would be good to probably 1,000 HP, so I wouldn't worry about strength. However, being lighter, you would/should have the crank rebalanced.

Craig

Do many cars still use the steel strut anymore? There was an episode of "How it's Made" with pistons as one the subjects. They had a rod of aluminum. Narrator said, for this model piston they need x amount. Machine cut off a length & fed it to an automated lathe. All the machining was done in a few seconds. Machine stopped, feeler gauge devices came out and checked. All was apparently OK so out it went to another machine for drilling and another piece of aluminum came in. No sign of steel struts there.

thanks craig i will tell my machinist ;0)

also if anyone is wondering....and not to call out a vender....but buying parts directly from egge is about 1/2 the price on some things and 3 times less on other parts.

i may post a price comparison on my blog without naming venders.

Hank

here is an update.

Jack Vines=Awesome! i have asked a billion questions and this guy just keeps on answering me, no worries. what a great guy!


i am going to be getting a competition balanced crank .010/.010 under, rods, pins, rings and 374" pistons from Jack. all Packard ;0) and for an excellent price! thanks again Jack! you da man!

getting cam reground for a mild performance enhancement by Jack.

going to bore the motor to 4.125 to make the 374" pistons fit.

later i will buy some higher lbs rated valve springs from Jack to go with the Cam modification, before i put it all together again.

3 angle valve job w/ hardened exhaust valve seats. but the valve guides are warn, so i may need to put in new guides or get oversized valves. as long as they are Packard valves i am good, otherwise i'll just put in new valve guides.

i wont have enough money left over to buy all the gaskets and bearings, but i'll have the machine work done and the parts to put in it and in a few months i'll get the gaskets, etc....

next years salado this will be in the car i hope.

later all.

Hank

but the valve guides are warn, so i may need to put in new guides or get oversized valves

These engines don't have replaceable valve guides. Either ream the head for valves with OS stems, or do as most rebuilders do and machine for replaceable guides (usually bronze?) sized for standard valves. Of course make this choice and do that work before grinding the valve seats.

understood. i am going to talk to the machinist in person today. (picking up parts he doesn't need anymore since i am getting them from Jack) we are going to talk about valve guides...

by new ones that was what i meant...machining and putting in replacable ones.....i will probably do this so i don't have to buy new valves.

okay talked to the machinist.

1. going to put in positive valve stem seals

2. need all 8 new exhaust valves, mine are toast. pitted and bad

3. Heads will have 3 angle valve job

4. will machine for new guides, choice of either bronze or cast steel, but since i'm not going to be racing i'll probably just go with the cheapest cast steel. unless Jack says it wont be right.

5. picked up the block to have the crack fixed soon and to get all the rust off of it. grease is all gone.

6. picked up the cam to send in to Jack for regrind to mild.

7. picked up the crank and pistons/rods to put back in storage

8. left the rocker arms to have the rocker arm stems reground smooth, most showed wear, but not bad. might as well do it.

9. after crack in block is fixed and parts from Jack come back to me, i'll take the block back and have the cam bearings fitted and the block bored to 4.125 for the new pistons.

10. will order the new valve springs from Jack to go with this cam so i can put the heads together.

11. will order gasket set and bearings to put motor all together.


i'm sure there are some things i'm missing in between those steps, but that is the basic plan anyways.

all together it should be around $2,000 and i'll be ready to put things back together.

have a good one,

Hank

Hank,
After seeing the repair already done to this block, and the crack repair that you are having done, and now boring out the block. Will this block take all of this? Will the block be sound enough for motoring. I am betting that one day you might just want to romp on the gas..............

I do not know ANYTHING about what you are doing, just keep thinking about how much money you are putting into it. You know where there are V8 blocks. Just not the one that came with your car.