Ok moparters, I know opinions are like other things, but heres the scenario. Im building a mild street engine that will never see a race track, it will have a mild cam, 4bl, 4 speed and 3:08 posi gears in A 4200 lb car. The guy im getting my parts from is a hard core racer and swears forged are the only way to go and that even the Egge Machine USA cast pistons Im considering are total junk. Forged pistons and ring package from him is going to cost me 980.00 Cast piston and rings are around 450.00. Money is an issue, I want to sleep at night.All my other peeps say the cast will work fine. Lets hear your input. BTW i ran cast in my 440 With no problems. AAlso theres a 4 week wait on the forged. Ok, let er rip.....thanks

I'll go out on a limb and say cast may be best in your application. You can run tighter wall clearance which reduces noise and wear. Weight is not a big issue with moderate cam/moderate RPM.

Goes without saying whichever you choose needs to be done correctly/carefully. Compression, wall clearance, ring gap all dialed in for the piston. If your engine guy isn't comfortable dealing with cast pistons, is he the right guy for your situation?

cast

He may be on to something. I couldn't in 4 tries get a Speed pro cast piston than had round pin bores . I reinstalled the beat up piston and moved on. There are some junk parts being sold. A proper cast piston sounds good enough for your application. What engine combo is this for?

.... for a cost factor and mild-street ... another vote for cast ...

Summit has Ross forged in stock for under 600 with free shipping, I would go with those, saw too many problems with some cast stuff.

Stock were cast and I cant recall seeing a piston being the reason a stock engine failed,usually it was a rod knocking.

I did see a hyper fail,ruined all but I think one head on the engine.

A GOOD cast piston is always better for street and good for a little track use also...and it won't sound like a diesel when cold!

Forged...

Strength...

Especially with what is today called 'fuel'...

sure forged will be stronger, but where is he getting his pistons that cost $900? I'd expect to pay in the $600 ball park for a set of forged pistons.

but for what you want, cast will be fine. my 5.9L has stock cast pistons in it, a cam, intake, headers. it's putting 285hp 325 tq to the wheels and running 14.3 with abysmal 60' times on street tires (indicating it has the power to run 13s if I can get it off the line) in my 4000 lb pick-up truck.

If cast pistons work in that application, why wouldn't they work in your 4200 lb vehicle?

as mentioned, you just need to be sure your tune is in the ball park and keep it from detonating. but even if you had forged pistons, detonation will still wreak havoc on your motor and tear up rod bearings/main bearings, and forged pistons won't protect the bearings.

Well, just to throw out another curve ball, your post sounds like what you are building isn't a Mopar? I've read on the Packard forum that Egge cast pistons don't have expansion struts like the factory cast pistons did, and so must be run with a lot more clearance than the factory cast pistons, and for that and maybe other reasons aren't really suitable even for street high performance driving. And so I pulled out one of the cast pistons out of the rebuilt Packard V-8 motor that I picked recently, and the reports were right - no expansion struts. So I'm mulling over whether to use the Egge cast pistons I already have or pay the extra money for forged, even for a true street engine that won't have much over 300 hp.

If you just want it to run, cast will be fine. If you notice, some of the responders stated a GOOD cast piston is fine, not any cast piston.

Here are the things to consider, 1) The $350 cast piston is probably not in the good category, 2) you will not have a good selection of compression heights.

Again, if you just want it to run, this likely does not matter.

If you want a good motor with the possibility to step it up in the future consider getting the Probe SRS pistons. About $625 with rings. My machinist and others (mostly Chevy guys) say it is a decent piston and a good value. This is what you get: 2618 high silicon (low expansion, tighter clearance) forged piston, 1/16, 1/16, 3/16 ring pack, 2.060" compression height, and lighter piston.

For an extra $200 today, you get so much more, and a buch of potential without having to get back into the short block, IMO.

So much BS, so little time.....

First of all, I would NEVER use an Egge piston when there was a decent Sealed Power or Silvolite piston available. Or Badger or any of the other name brand pistons. IMHO Egge is a place where you get pistons for engines that are going in show vehicles and will never be run hard.

Second, if your characterization of your engine and its uses is correct there's no way you need forged pistons. No way. Millions of production engines used regular cast pistons and made some pretty good horsepower with really good longevity.

Third, I think you should take a tube of K-Y jelly with you the next time you visit your "friend". $900 for a set of forged pistons is criminal, or at least illegal in several states. Do some shopping around and you'll see what I'm talking about. For starters, go to www.flatlanderracing.com and see what they have to offer. Then call them if you have an engine for which custom pistons are needed. Or if it's off-the-shelf, CNCMotorsports.com can get you a really nice price. At this point I will add that those are for comparison purposes. There are several hard part dealers that are Moparts.com sponsors who speak MOPAR and will probably get you the best deal in the end.

Fourth, so far I haven't mentioned hypereutectic pistons. If your engine is one for which there are hypereutectic pistons, they can be a superior product and there are some that may fill your needs.

Fifth and last...WEIGHT. If your engine is a MOPAR engine it has the heaviest pistons known to man. It'd be worth spending the $200 or so over the cost of stock replacement pistons, plus the $200 or so for balancing the assembly, to have a much lighter piston/pin in your engine. You'll notice the difference, even just driving around. For example, my friend who restored a 1949 chevy truck replaced the cast iron piston with much lighter aluminum ones and said even at 216 cubic inches, the difference was quite noticeable. So give some serious thought about weight.

End of lecture.

R.

PS: Please feel free to PM me with specifics and further discussion.

what Packard do you have? I worked for Pat Aldrich for awhile at Aldrich restorations, who specializes in packards. we worked on mostly 1955 and 1956 Caribbeans, but also had the occasional Clipper, Patrician, and some stuff from the 30s -- various business coupes, etc.

i just ordered forged stroker pistons for my 520 ci. from CNC motorsports,over 100.00 bucks cheaper than summitt.and only 14.00 bucks shippin,and im in FL.it was like 529.00 bucks.

Thanks for all the great replies. I didnt want to disclose the make for obvious reasons since it wasnt a Mopar, however I value the knowledge on this board for the last 13 years and knew i could get some good feedback. The engine is 394 Oldsmobile, about as obsolete as they come. It was a great engine with lousy transmissions.Thats why Im doing A 4 speed conversion behind it. As for the piston, they are totally custom pieces from a specialist whoraces these engines. He told me before I got started the pistons wouldnt be cheap. At this point I know for sure we will have more control over final compression ratio with the custom forged. I think he has Wiseco make them and there price was a few dollars more.Thanks for the heads up on the Egge shortcomings. Sorry for posting about a non mopar but i know the knowledge is here. I think Ill go with the forged. This car will be driven alot so i want it to last.

Before you do anything you need to find a copy of the Street Rodder series on the 394. I believe they used a 400 chevy piston and some bigblock chevy type rods with an offset ground crank. That did three things: Got more cubic inches, saved weight in the reciprocating assembly, and allowed the use of easily available and less expensive aftermarket high performance parts.

I really believe it's worth your while.

R.

Web search results, "The guy who built the bottom end (short block) with Doc is Kerm and can be reached at 717 334-6882 most any weekday. He can tell you anything you want to know about that engine build. He's a lifelong Rocketeer! He's sold his shop to his son in law, but still has a bay there where he works on projects that interest him.
The shop is K.A.R.S. in Gettysburg, PA."

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