Chrysler 354 Hemi .060 forged pistons
jboymechanic
Posted 2013-08-08 10:03 PM (#390408)
Subject: Chrysler 354 Hemi .060 forged pistons



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Anyone know of any suppliers of forged pistons for a 354 Hemi with a .060 over bore? Hot Heads has custom made ones from Ross Racing, I was wondering if anyone was aware of any other quality suppliers as I would like to shop around. If it comes down to it, I will order the pistons from Hot Heads or direct from Ross.
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GregCon
Posted 2013-08-08 10:25 PM (#390409 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Not sure but I think a 392 piston, standard, can be used in some cases.
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MOPAR-TO-YA
Posted 2013-08-09 12:59 AM (#390444 - in reply to #390408)
Subject: RE: Chrysler 354 Hemi .060 forged pistons


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Egge Machine has all kinds of pistons, and they manufacture them..................................MO
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56Fanatic
Posted 2013-08-09 1:11 AM (#390448 - in reply to #390444)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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IIRC the compression height of a 392 piston is 0.0285" higher than a 354.
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Mopar1
Posted 2013-08-09 8:38 AM (#390487 - in reply to #390448)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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If you use 392 pistons order a C/R 1 point higher than you want & it'll come out what you want.
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Mopar1
Posted 2013-08-09 8:45 AM (#390489 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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"Wayfarer" here on the Board is Gary at Quality Engineered Components, check with him for a quote.
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Shep
Posted 2013-08-09 9:06 AM (#390495 - in reply to #390489)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Why forged pistons, not really required for most engine builds in our cars.
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jboymechanic
Posted 2013-08-09 9:33 AM (#390499 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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We're not doing a stock rebuild, I hope to be in the 400 hp and 500 ft-lb range when done. I also plan on enjoying the car for a long, long time and while cast is ok forged is better. Same reason I've been using all stainless steel fasteners in the car (other than high stress applications, such as suspension and body mounts where I've been using grade 8 hardware), updated to disc brakes, updated the rear end to a Mopar 8 3/4" with 489 carrier, updated to an alternator and so on. Good enough is ok, but I prefer better.
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GregCon
Posted 2013-08-09 1:26 PM (#390520 - in reply to #390499)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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You can do what you want, for sure.

I'm not sure forged pistons are better for a FL car. It's kinda like the idea that SS fasteners are better - maybe, but also maybe because of the sex appeal that magazines attach to them.

My most recent engine - the 354 for my '58, uses cast Egge pistons. This is the first cast engine I have done in a long time. The rest have all used forged. I could have afforded forged pistons from Arias if I wanted, but I chose the cast pistons because......they are undeniably quieter all of the time, not just when cold. I'm also not convinced the forged pistons being offered by the aftermarket are truly a long-life proposition. Their shorter skirts, alloy composition, looser bore tolerance, and various other features are all geared toward HP production which is often at odds with durability. The idea of a forged piston bobbling around the bore every time I start the engine cold doesn't speak well for long life. It's tough on the rings, too. Do you know anyone with a 200,000 mile history using Ross pistons? I don't. I also don't plan to drive around with my engine pinging all the time, so there goes another good reason to use a forged piston.

The average cast piston of today has way more technology behind it than a simple forged piston.

As for SS fasteners....why would you want to use a fastener that has usually a lower tensile strength and much higher tendency to galling than a good Grade 8 carbon steel bolt? I sometimes use SS but I'm selective about when I do it. A 55 year old FL car is not that corrosive of an environment any longer. Chances are your car is garage kept and sees light use in good weather. Not a real need for SS fasteners.

Most major oil companies - guys who know more than all of us - use SS offshore due to sal****er corrosion. But they've also gone to a passivated SS fastener - basically a mega-buck SS fastener with a special surface finish - because they've gotten sick of all the galled threads.







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57chizler
Posted 2013-08-09 3:12 PM (#390532 - in reply to #390408)
Subject: RE: Chrysler 354 Hemi .060 forged pistons



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The OP is working on a couple of misconceptions, that forged pistons are "better" and SS hardware is "stronger".

Cast pistons and iron hardware will be just fine for your build.
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jboymechanic
Posted 2013-08-09 3:29 PM (#390537 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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From what I've read a good rule of thumb is to use forged pistons when the compression ratio is 10:1 or higher and the targer/estimated horse power is 50 or more over the cubic inch displacement. I'm right on that line, so I thought it would be wise to err on the side of caution and go with the forged. We would opt for a hyperutectic but I'm not aware of any available for a 354 with a .060 overbore. We've been talking with Bob at Hot Heads and will probably just stick to what he recommends.

Greg, as for the stainless, of course it's about sex appeal, isn't that what classic cars are all about? I just happen to appreciate the clean look of new stainless hardware and I'm 31 and hope to have the car until I'm forced to give up driving so I want all the hardware to appear as new for as long as possible. Another thing I did that was never done at the factory was to paint the inside surfaces of the car with POR-15. The under side of the dash, inside the doors, inside the rear quarters, the underside of the roof, all of it. This was never done from the factory, but I feel better knowing that I'm protecting my investment and making it better than it was. I'm sure you can appreciate that because I've seen pictures of your work here and it is excellent and beyond what the factory ever did. So I guess I better leave it there before I hijack my own thread, let's talk pistons.

Edited by jboymechanic 2013-08-09 3:29 PM
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Powerflite
Posted 2013-08-09 3:51 PM (#390538 - in reply to #390537)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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The best thing about a .06" overbore 354 is that you can get pistons CHEAP. Look on ebay for some used standard 392 forged pistons with 11:1 compression that will give you 10:1 in your 354. I think I may even have a set. Hypereutectic would be best, but the selection isn't there to support your motor. But if you are going to shell out serious $$ for custom pistons, it seems that there has got to be a company that can build custom hypereutectics.

Oh, and I always use stainless in certain places - like exhaust. I like to be able to get exhaust bolts off without using the torch.

Edited by Powerflite 2013-08-09 3:57 PM
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56Fanatic
Posted 2013-08-09 7:19 PM (#390567 - in reply to #390538)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Powerflite, please explain to me how using an 11:1 392 piston will give you 10:1 in a 354. Like I said above the compression height is 0.0285" taller than a 354 piston. It seems to me this will move the piston crown 0.0285" further into the combustion chamber, not to mention any amount milled off the block and heads to achieve flat surfaces. Don't doubt you are right, just can't understand it.

Thanks,
Loyd
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Shep
Posted 2013-08-09 7:43 PM (#390570 - in reply to #390567)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Both 10 or 11 to one is an issue with pump gas in an iron head engine, 93 octane will still be on the ragged edge of detonation under load, some dist recurving will be in order here. I target a max of 9.5 when we build any iron head engine, unless it is running an aggressive cam that tends to bleed off some compression at low speeds.
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Powerflite
Posted 2013-08-09 8:30 PM (#390577 - in reply to #390567)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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The main reason for the compression ratio difference is the smaller swept volume of air from the shorter stroke of the 354. Less air drawn in means less resulting compression if the height is the same.

I have run a 392 with 10.5:1 pistons using mid-grade pump gas for 15k miles. My cam is a street performance grind - I don't remember the specifics. I believe this is a stock compression ratio for '58 motors. And hemi motors need less advance than wedge motors anyway. Is it ideal with today's gas? Maybe not, but it works.

Edited by Powerflite 2013-08-09 8:33 PM
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Mopar1
Posted 2013-08-09 10:58 PM (#390604 - in reply to #390577)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Powerflite - 2013-08-09 7:30 PM

The main reason for the compression ratio difference is the smaller swept volume of air from the shorter stroke of the 354. Less air drawn in means less resulting compression if the height is the same.

I have run a 392 with 10.5:1 pistons using mid-grade pump gas for 15k miles. My cam is a street performance grind - I don't remember the specifics. I believe this is a stock compression ratio for '58 motors. And hemi motors need less advance than wedge motors anyway. Is it ideal with today's gas? Maybe not, but it works.
Exactly on the swept volume. OEM 392s were 9.25 or 10:1. Generally speaking a hemi is supposed to run on the same octane as a wedge with 1 point less C/R.
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1959Dodge
Posted 2013-08-10 6:59 AM (#390624 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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I've had the KB Alloy pistons in the 440, (475 HP, 535 ft/lbs torque) for 3 years now.

They are quiet, rev fast (cause of light weight), and the engine never uses even a drop of oil, runs on 87 pump gas, No detonation, (aluminum heads).

I had put TRW forged pistons in the 426 Wedge in my 64 Dodge. That engine sounded like a freakin diesel, especially when cold
and even when hot they were not all that quiet, and running around 10 to 1 compression, I had to really retard the timing to
(Minimize detonation--alto I could never eliminate it entirely.

That engine was replaced by a 413 bored out to about 420, and regular cast pistons, compression about 9.3 to 1.
The engine runs great on 89 octane, (Not a trace of detonation and running about 34 - 36 degrees of distributor advance.
I've had this engine about 10 years now and I'm very happy with it.

My friend Aivar just finished a Stroker 440 engine with 500 HP, 10 to 1 compression, forged pistons.
He is not all that happy with the sounds the forged pistons make, (even when warm) and as mentioned,
detonation using 91 Octane is a real Pita for him.

Anyway some things to think about, from one that has "been there and done that"!

Gary
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GregCon
Posted 2013-08-10 9:29 AM (#390634 - in reply to #390624)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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I'm not against forged pistons...and the fact that they can be made to any specs is a plus. I just don't know if they are best for every engine. That's all I'm sayin'.


We used to buy 440 powered cars for $150. We'd pull the 440, put in new bearings and hone the cylinders and use new rings. I think PAW used to sell a kit for something like $54 that came with all those parts plus gaskets. The stock cast pistons were always reused. No one bought new pistons. Anyway, that was our rebuild along with a cheap valve job. We'd then drive the crap out of it with as much timing as we could dial in - if we didn't hear pinging that meant you needed more advance. After a while, maybe a year, we'd notice the engine was not doing well so out it would come. You'd slide the piston out of the bore and the ring lands would fall on the ground. That's what 6000RPM and lots of detonation would do. Then it was time to go find another 440....





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Shep
Posted 2013-08-10 10:08 AM (#390639 - in reply to #390634)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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I think we all need to keep in mind any engine built at the factory advertising 10:1 compression fell somewhat below that, when checking my Stage111 Max Wedge, using deck height, gasket thickness and head cc specs it worked out to 11.8 not 12.5, thus the blueprinting began.
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GregCon
Posted 2013-08-10 11:27 AM (#390642 - in reply to #390639)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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That's why my 354 worked well with the 392 pistons. It supposedly brought the compression up to around the published value.
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wayfarer
Posted 2013-08-10 11:32 AM (#390644 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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If the OP wants 10:1 c/r he will be using a forged piston. There are no cast pistons in anything but oem numbers and places like EGGE take some generous liberties with the advertised numbers. In the FWIW department, the EGGE piston is from the, now ancient, Hy-Duty Piston molds.
As to some of the other issues presented, we have not sent a rebuilt EarlyHemi out of our shop with anything other than 10:1 forgings in over 10 years and this includes some quasi-resto jobs where some of the grampa-style owners would definitely call if they had issues with noise-smoke-fuel or anything else that they didn't think was right. I just don't hear complaints.

And please, don't compare 10:1 in a Hemi engine with 10:1 in a wedge headed engine. They are simply not the same, and do not have the same operational characteristics.

If anyone is considering forged pistons I am currently offering them at $750/set w/pins.

As to using a 392 piston in a 354, you will LOOSE compression simply due to the smaller swept volume as previously mentioned. Go buy a calculator and figure it out for your self.

Edited by wayfarer 2013-08-10 11:36 AM
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56Fanatic
Posted 2013-08-10 11:55 AM (#390647 - in reply to #390644)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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<p>Wayfarer, what compression can I run in my 354 hemi build that will run reliably on regular unleaded? Oh, and what is the block deck height on 354 and 392 hemis?</p>

Edited by 56Fanatic 2013-08-10 11:58 AM
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57chizler
Posted 2013-08-10 1:58 PM (#390655 - in reply to #390644)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Egge has off-the-shelf pistons that may or may not produce the CR they advertise but they can also make custom cast pistons per your spec.
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GregCon
Posted 2013-08-10 2:21 PM (#390658 - in reply to #390655)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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I wouldn't want 10:1 CR in an iron headed engine anyway. I don't remember the details now but my engine wound up somewhere around 9.25:1 actual which is a lot more comfortable with pump gas and smaller cams.

As for complaints with forged pistons....the average grandpa or even the average 40 year old might not realize what he is hearing. Actually, the average grandpa might be too deaf to hear any noise anyway! Here's my take - most guys putting a rebuilt engine in a FL car are just glad to get it all back together and running. They're not nitpicking about a little mechanical noise. And they drive the car not all that much, so longetivity issues aren't going to show up for decades, not just years.

As for street rod guys using early Hemi's...well they're never the standard for low noise anyway.

I'm in the somewhat rare (for me) position of having two Hemi cars running at the same time with fresh engines. I can drive them back to back and there is no mistaking the Chrysler, with its cast pistons, is way more 'OEM' than the Plymouth with it's forged pistons. You just don't hear all the noise and 'uncertainty' coming from the block.

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jimntempe
Posted 2013-08-10 4:18 PM (#390662 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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I'm always mystified by the worry people have over getting their engines rebuilt to they can run on "regular unleaded" so they go to lower CR. Most of these cars don't ever do 2000 miles a year. Even at 10 mpg that's just 200 gallons. If you had to pay an extra 25 cents a gallon to use premium you are only talking about another $50 a year for the use of premium fuel. Why lose the performance to save $50 a year?? And the higher CR would probably give you better gas milage!!
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GregCon
Posted 2013-08-10 4:32 PM (#390663 - in reply to #390662)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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I didn't say regular unleaded, I said pump gas. Premium fuel is a given.
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56Fanatic
Posted 2013-08-10 6:05 PM (#390669 - in reply to #390663)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Jimntempe,
Iif your comment was aimed at me, I just want my Chrysler as a smooth running crusier. I already have a BUILT 400 cu '65 GTO that requires pump premium and it can be expensive to drive, but it's alot of fun. Besides my 1956 New Yorker St. Regis that I drove when I was seventeen ran just fine on regular so I think my lates build should run on regular too. Just sayin'.
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jboymechanic
Posted 2013-08-10 10:23 PM (#390695 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Now we're having a hearty discussion. Yes, I'm more than happy to run 93 octane in my car. I'm going to be driving it to plenty of shows and would hope to hit shows like Back to the Fifties in the twin cities and Hershey, PA. Those are good, long drives from the Milwaukee, WI area. I've done as much as 5,000 miles a year in a classic car, so that is my bench mark. I will be using the stock cast iron heads.

Greg, what kind of 392 pistons did you use in your 354? Also, the standard bore for a 392 is 4.000 inches, a 354 bore is 3.9375 plus 0.060 will give me 3.9975 so I'd really need the shop to bore out 0.0625, is that what it takes?

Wayfarer, PM will be sent shortly.
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wayfarer
Posted 2013-08-10 10:31 PM (#390696 - in reply to #390647)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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56Fanatic - 2013-08-10 8:55 AM

Wayfarer, what compression can I run in my 354 hemi build that will run reliably on regular unleaded? Oh, and what is the block deck height onĀ 354 and 392 hemis?



Regular unleaded, 87 rm octane, is an issue in some parts of the country, especially now with 15% alky. I would still run 10:1 c/r and deal with it however I needed. Your needs and tolerance to the issues mentioned are likely to be different than the 'next' guy so only you can make the call.

As to deck height, the tallest numbers that I have on record: 354-- 10.390" ; 392-- 10.880"
We have measure plenty of variations and the most common numbers are 10.320 and 10.870

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56Fanatic
Posted 2013-08-11 1:47 AM (#390709 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Yet the 392 deck height is purported to be 0.500" more than a 354. Which, to me makes running 392 pistons in a bored out 354 somewhat problematical.
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jimntempe
Posted 2013-08-11 3:23 AM (#390717 - in reply to #390669)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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56Fanatic - 2013-08-10 3:05 PM

Jimntempe,
Iif your comment was aimed at me, I just want my Chrysler as a smooth running crusier. I already have a BUILT 400 cu '65 GTO that requires pump premium and it can be expensive to drive, but it's alot of fun. Besides my 1956 New Yorker St. Regis that I drove when I was seventeen ran just fine on regular so I think my lates build should run on regular too. Just sayin'.


It wasn't aimed at anyone in particular. I did interpret the comments in general to be referring to the notion that the goal was to use the lower octane pump gas and it sounds like I might have misinterpreted the intent of some of the comments. I do hear a lot of people talk about wanting to rebuild so they can burn "regular gas", which like I said, mystifies me.... what I spend on gas is a very small part of what these classics cost me to own.
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Mopar1
Posted 2013-08-11 8:24 AM (#390722 - in reply to #390709)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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56Fanatic - 2013-08-11 12:47 AM

Yet the 392 deck height is purported to be 0.500" more than a 354. Which, to me makes running 392 pistons in a bored out 354 somewhat problematical.
For those who go for big, instead on minimal, overbore using 392 std pistons is common, as is 354 std in 331s.
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Beltran
Posted 2013-08-11 10:31 AM (#390735 - in reply to #390709)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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56Fanatic - 2013-08-11 1:47 AM

Yet the 392 deck height is purported to be 0.500" more than a 354. Which, to me makes running 392 pistons in a bored out 354 somewhat problematical.


As quoted from The Complete Chrysler Hemi Engine Manual. " Due to its increased stroke, the decks (head surfaces) were raised, hence the 392s are often referred to as a raised block, the 331-354 as standard, or low blocks. A ramification of increasing the deck heights was that the heads were now spaced further apart than with the low blocks. This problem was addressed by adding material to the intake manifold face of the heads. Along with the increased deck height and modifications to the heads, the connecting rods were also lengthened. To keep rod angles from becoming severe, the connection rods were stretched from 6.125 to 6.95-inch. "

The pistons did not make up for the deck height. The rods did.
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Beltran
Posted 2013-08-11 11:03 AM (#390745 - in reply to #390735)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Here is the page on this piston swap. Read the right column.



(392-354 pistons (465x640).jpg)



Attachments
----------------
Attachments 392-354 pistons (465x640).jpg (249KB - 280 downloads)
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56Fanatic
Posted 2013-08-11 11:12 AM (#390747 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Beltran,

That's exactly right. But, if you take the deck height-stroke/2-rod length you will arrive at the compression height of the pistons.

For the 354 (using nominal specs) this equals 10.37"-1.8125"-6.625" which gives 1.9325" as the compression height.

For the 392 (using nominal specs) this equals 10.87"-1.9530"-6.956" which gives 1.9610" as the compression height.

The difference is 0.0285" which means if you have a less than nominal 354, you better do some darn close checking before you go stuffing 392 pistons in a 354 !
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jboymechanic
Posted 2013-08-13 5:25 PM (#391066 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Well after talking to Bob and Eric at Hot Heads we're going to use cast standard bore 10:1 (1958) 392 pistons. Eric has this setup in a 354 he's running in a 1958 Plymouth and he's had no trouble for 19 years and 90,000 miles. His compression ratio is 10.25:1, stock 354 heads other than an upgrade to 2 inch intake valves and some minor milling. I'm intrigued, but I also trust them. We're more interested in low end torque (4800 lb car with 3.23 gears and 30 inch tires), which they state the motor will make plenty of with the correct cam and timing. So here we go.

Edited by jboymechanic 2013-08-13 5:26 PM
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wayfarer
Posted 2013-08-15 12:25 PM (#391412 - in reply to #391066)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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jboymechanic - 2013-08-13 2:25 PM.... going to use cast standard bore 10:1 (1958) 392 pistons. Eric has this setup in a 354.... His compression ratio is 10.25:1, ... So here we go.


The 'math' simply doesn't support this c/r without significant cutting on the decks or heads...

Good luck.
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Powerflite
Posted 2016-12-20 3:19 AM (#529249 - in reply to #391412)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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Wayfarer, do you know what the volume of the 354 combustion chamber is? The article that Beltran posted states that it is at 105.5cc. That is right in between the 392 (110cc) and the 331 (100cc). Does that sound right? I am wondering if you could get alot of your compression back up by using 331 heads when you swap to 10:1 392 pistons.
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wayfarer
Posted 2016-12-20 1:53 PM (#529288 - in reply to #390408)
Subject: Re: Chrysler 354 Hemi .060 forged pistons



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For whatever reason(s), we have found a lot of variation in head cc's. The current 354 project measures 102cc.
The biggest problem most folks have is being able to determine what heads are untouched and which have been cut. I have not yet taken the time to inventory the heads that I have to try and determine cc vs. casting number or, to measure the heads to develop a measurement of some sort from point 'a' to point 'b' to help determine if a substantial cut has been made. Obviously, with some sort of benchmark number, a big cut could be seen but I have no idea how much variation was allowed at the factory in something like the deck to the rocker arm stand mounting pad so a small clean-up cut could go un-noticed.
My (personal) problem is that the older I get the less time I seem to have for such adventures and I just deal with each engine on an individual basis and make all of the parts play nice together for the intended use.
Now, if some young'un wants to spend a week in the shop measuring stuff......
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