Packard V8 piston problems

PackardV8 · Post by **PackardV8** » Tue Sep 26, 2006 11:02 pm

Greetings, All,

As many of you know, we do stock and performance rebuilds on Packard and Studebaker V8s. As often as we have done them, there is something to be learned every time. We just finished another complete stock rebuild of a 1956 Packard 352” and put it on the test stand. Everything had been done to spec, crank .010” under, cylinders .030” over, cam reground, new lifters, rocker tips reground. It started and ran fine, but there was a bit of a knock which should not have been there. As the water temp went up, the knock got louder. Nothing to do but shut it down and open it up and find the problem.

When we got inside, it took about an hour of looking to finally notice traces of aluminum on the edge of one of the crankshaft counterweights. Close examination showed the skirt of one of the pistons was brushing the crank. As the engine got hotter, the piston expanded, the bearing clearances got larger and it tapped louder.

The piston wasn’t hurt. We dressed the piston skirt, smoothed the casting roughness on the crank and the clearance opened up to the .015” or so the other cylinders had. With two people working on the problem, at $100 an hour of shop time, the mis-made piston cost us $400. Just one more reason I don’t like the Egge Machine cast repo pistons.

On the one hand, without Egge Machine, we wouldn't have any cast repo pistons, but more often than not there are issues with them. They have to be set up with at least .0035" clearance, instead of the OEM .0015". Even at that, they tend to run hot, sometimes scuff and generally give a bad account of themselves.

Because of this, we built a test stand and run in each engine before it is shipped. It adds to the expense of the rebuild, but it is the only way to insure the quality of our product.

Guess I am going to have to step up and order a run of forged pistons in stock configuration. The Packard V8 uses a 4" to 4.125" bore piston with a very tall 2.070" pin height and a .9803" piston pin. The early big block Mopars 413" were the closest match, but they are .050" short and the pin is .091" larger.

Any suggestions as to which piston manufacturer might be the most interested in a project like this? Ross once quoted $650 a set in small batches, but they are race-oriented and specify more wall clearance than is ideal in a stock rebuild. Would be good to find a piston which would stay round and install with .003" max clearance. Suggestions are welcomed.

Thnx, jv.

Ed-vancedEngines · Post by **Ed-vancedEngines** » Wed Sep 27, 2006 12:21 am

Jack,
I work with BRC on all of my custom pistons. They are a small race oriented company that was one of the original mfg of racing products way back when. Jay is the owner and both Jay and his lead design engineer, Steve are very easy to work with on things that are different than the normal and you do not have to pay an arm and a leg for them to do it for you. I am not sure just what all alloys they have available to work with for blanks, but I am pretty sure that they are not doing castings.

The other approach is to check the available pistons from United Machine's KB Line of Hypereutetic, and see if any machine work can be done with any of those to fit the bill for your needs. At KB I deal with Kevin.

I am also thinking of a smaller but up and coming company that may have a low expansion rate piston available or maybe can work with you that is named Mahle.

Ed

Unkl Ian · Post by **Unkl Ian** » Wed Sep 27, 2006 2:36 am

What about running longer rods,then you'd have more piston options.

TORQUE INC · Post by **TORQUE INC** » Wed Sep 27, 2006 3:30 am

Pistons are very similar to a 425 cadillac

For customs try Probe racing and talk to Shawn Mendenhall

Very nice guy easy to deal with.

That would be my suggestion based on my dealings with other companies

Only other company IMO worth a try would be Diamond

a 4000 series alloy would be better than the 2618 for a mild rebuild.

Good luck TI

Sir Yun · Post by **Sir Yun** » Wed Sep 27, 2006 5:03 am

" am also thinking of a smaller but up and coming company that may have a low expansion rate piston available or maybe can work with you that is named Mahle"

I wish i owned a small company with 37.500 employees

Barry_R · Post by **Barry_R** » Wed Sep 27, 2006 7:28 am

I'll second Torque's opinion. I am a dealer for and geographically close to Diamond - - and would definitly look at them for these. They are about the fastest around for custom stuff - - 2-3 weeks. And they will do a 4032 alloy that'd be better for what you are doing than 2618.

PM me and we'll get the data to for check blank availability. etc.

PackardV8 · Post by **PackardV8** » Wed Sep 27, 2006 10:27 am

As always, this list is the greatest - thanks for the good suggestions:

1. Unkl Ian - the Packard rods are 6.78125" long, 2.250" journal, 1.060" width. Haven't found an OEM rod which can be made to interchange. All leads appreciated.

On the strongest Packard we have built, we did go to longer rods and Mahle pistions - using Oliver BBC 7.250" rods with SBC bushed pin ends. They will never break, but at $1600 a set, aren't really practical for our other engines.

2. Torque, Inc - as always, you appreciate the non-bb engines. The 425" Cad is somewhat close to the Packard, but almost as rare and am not aware of anything other than OEM replacements for it.

3. Ed - we have been through United's catalog and on-line listings backward and forward and haven't found anything closer that the 413" Mopar and the 425" Cad and these aren't really useable in stock rebuilds.

One more question for those who know - to whom would you go for .9803" ID x 1.500" width pin bushings?

thnx, jv.

needforspeed66gt · Post by **needforspeed66gt** » Sat Sep 30, 2006 5:48 am

Sir Yun wrote:" am also thinking of a smaller but up and coming company that may have a low expansion rate piston available or maybe can work with you that is named Mahle"

I wish i owned a small company with 37.500 employees

lol- I was going to say something smilar. Being that mahle is soo large, profit margins are very important to them as compared to having customers happy with small one-time runs of old pistons - I have tried to get them to modify some of their off-the-shelf cast pistons in the past with no luck. That price you were quoted by ross is not bad at all considering the application and low volume...if it is made out of a 4032 forging you should have minimal issues with piston to wall...what operating temp does that motor obtain?

PackardV8 · Post by **PackardV8** » Sat Sep 30, 2006 6:33 am

Operating temp with OEM pistons and .0015" clearance is your usual thermostat-controlled 180 degrees.

With the Egge Machine cast pistons, unless the clearance is opened to at least .0035", they will scuff, drag and run 225 degrees or more in the same engine.

Ed-vancedEngines · Post by **Ed-vancedEngines** » Sat Sep 30, 2006 6:50 am

I again suggest you to call to BRC. It is a very old well established company and all you have to do to talk with the owner is to ask for Jay.

Thier prices are in my opinion very reasonable and I am sure you can easily get Jay to work with you on a variety of alloys if he has it or can get it.

BRC Racing
1-800-522-7478

Ed

machine shop tom · Post by **machine shop tom** » Sat Sep 30, 2006 9:51 am

I curious now. Does anybody know who makes Kanter's pistons?

tom

PackardV8 · Post by **PackardV8** » Sat Sep 30, 2006 6:34 pm

Hi, Tom,

AFAIK, Kanter, Tucson Packard, Packard Farm and the maddog on eBay are just re-selling Egge Machine pistons. No other known source.

thnx, jv.

machine shop tom · Post by **machine shop tom** » Sun Oct 01, 2006 10:57 am

PackardV8 wrote:Hi, Tom,

AFAIK, Kanter, Tucson Packard, Packard Farm and the maddog on eBay are just re-selling Egge Machine pistons. No other known source.

thnx, jv.

I suspected that.

Thanks!

tom

n2omike · Post by **n2omike** » Mon Oct 02, 2006 12:45 am

Years ago a guy I knew had some custom pistons made for an old RCH. Yes, OLD.... and not like anything commonly available now.

I believe he had them made by Arias.

If your other leads don't pan out, you might try them.

Mike@DiamondPistons · Post by **Mike@DiamondPistons** » Fri Oct 06, 2006 3:25 pm

PackardV8, please give me a call @ diamond pistons @ 1-877-552-2112 x 115. We can discuss the specs, and get a very friendly quote. I'm pretty sure I can get you something that will work perfect for you.

Thanks,
Mike Panetta