Cast or Forged Pistons
#1451962
06/12/13 10:39 PM
06/12/13 10:39 PM
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Joined: Jan 2003
Posts: 5,449 Woodbridge,CA
NAS Backyard
OP
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OP
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Joined: Jan 2003
Posts: 5,449
Woodbridge,CA
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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
1970 Challenger Ragtop 426 4 speed
1961 Olds 88 2 dr Sedan 394 4 speed GVOD
1968 Pontiac Firebird 428 4 speed
2000 Ford F-150
2002 HD Roadking
1961 Licence Plate collection
1995 Buick Roadmaster
www.nogreenautolaws.com
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Re: Cast or Forged Pistons
[Re: NAS Backyard]
#1451969
06/12/13 11:51 PM
06/12/13 11:51 PM
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Joined: Jan 2003
Posts: 4,437 Omaha Nebraska
Brian_wo
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master
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Posts: 4,437
Omaha Nebraska
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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.
who is that guy?
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Re: Cast or Forged Pistons
[Re: RSNOMO]
#1451972
06/13/13 08:01 AM
06/13/13 08:01 AM
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Joined: Oct 2003
Posts: 21,345 Marysville, O-H-I-O
70Cuda383
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Too Many Posts
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Marysville, O-H-I-O
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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.
**Photobucket sucks**
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Re: Cast or Forged Pistons
[Re: NAS Backyard]
#1451973
06/13/13 09:37 AM
06/13/13 09:37 AM
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Anonymous
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Anonymous
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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.
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Re: Cast or Forged Pistons
[Re: NAS Backyard]
#1451974
06/13/13 09:44 AM
06/13/13 09:44 AM
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Joined: Feb 2005
Posts: 4,318 Prospect, PA
BSB67
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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.
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Re: Cast or Forged Pistons
[Re: BSB67]
#1451975
06/13/13 02:28 PM
06/13/13 02:28 PM
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Joined: Jan 2003
Posts: 16,376
dogdays
I Live Here
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I Live Here
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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.
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Re: Cast or Forged Pistons
[Re: dogdays]
#1451976
06/13/13 02:49 PM
06/13/13 02:49 PM
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Anonymous
Unregistered
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Anonymous
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Quote:
If your engine is a MOPAR engine
The OP has not yet informed us what kind of motor he's rebuilding, but the fact that he has 3.08 gears and is even thinking about Egge pistons makes me think it is NOT a Mopar engine. If it is his 61 Olds, he may be able to get an off-the-shelf cast piston for it. If it's something else (like my Packard V-8), there simply may not be any off-the-shelf pistons available other than Egge. And a custom-made set of forged pistons ain't gonna be cheap.
If I'm wrong about it not being a Mopar engine, please excuse the digression.
Last edited by 413coronet; 06/13/13 02:53 PM.
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Re: Cast or Forged Pistons
#1451977
06/13/13 05:50 PM
06/13/13 05:50 PM
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Joined: Oct 2003
Posts: 21,345 Marysville, O-H-I-O
70Cuda383
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Too Many Posts
Joined: Oct 2003
Posts: 21,345
Marysville, O-H-I-O
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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.
**Photobucket sucks**
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Re: Cast or Forged Pistons
[Re: bonefish]
#1451979
06/13/13 11:18 PM
06/13/13 11:18 PM
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Joined: Jan 2003
Posts: 5,449 Woodbridge,CA
NAS Backyard
OP
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OP
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Posts: 5,449
Woodbridge,CA
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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.
1970 Challenger Ragtop 426 4 speed
1961 Olds 88 2 dr Sedan 394 4 speed GVOD
1968 Pontiac Firebird 428 4 speed
2000 Ford F-150
2002 HD Roadking
1961 Licence Plate collection
1995 Buick Roadmaster
www.nogreenautolaws.com
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Re: Cast or Forged Pistons
[Re: NAS Backyard]
#1451980
06/14/13 08:12 AM
06/14/13 08:12 AM
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Joined: Jan 2006
Posts: 8,162 USA
360view
Moparts resident spammer
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Moparts resident spammer
Joined: Jan 2006
Posts: 8,162
USA
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Quote:
At this point I know for sure we will have more control over final compression ratio with the custom forged.
The forged pistons conduct heat away from the crown better and this can allow a higher static/dynamic compression ratio than either conventional cast or eutectoid aluminum alloys
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Re: Cast or Forged Pistons
[Re: 360view]
#1451981
06/14/13 01:04 PM
06/14/13 01:04 PM
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Joined: Jan 2003
Posts: 16,376
dogdays
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,376
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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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Last edited by dogdays; 06/14/13 01:07 PM.
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