392 Hemi -- Heads and Flow

Discussion of the 331-354-392 HEMIs.

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Bored&Stroked
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Location: Columbus, OH
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392 Hemi -- Heads and Flow

Post by Bored&Stroked »

Hi Gang: I'm new to Hemis, but have lots of experience with other engines. Just bought a complete 392 (haven't opened it up yet) and am planning on building it as a blown motor for my 40 Merc. I've heard many say that the 392 heads don't flow as well as 331 or 354 heads, but is this anything to ponder? Would you guys just stick with the 392 heads if they are in good shape? Also, what about stroker cranks? They've made them for years, was wondering if anybody is running a stroker in a 392 and what you think about it. How good are the 392 cranks if I wanted to have them welded up and stroked. Obviously a billet crank is a possibility, but they probable run $2500+ dollars (probably more with todays steel prices). Porting and Valve Work --> have done lots of this on other engines, any books or articles on the old Hemi? Stock rods --> can they handle 6 - 8 lbs boost? Mains -- should I replace them with 4-bolt steel billet caps -- who makes the best ones?

Thanks guys, appreaciate any and all help.
57' 392 Hemi -- much to learn!
Bailiesdad
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Post by Bailiesdad »

Heads: 392 are fine, 331 55s are better 354 56 are the best.
Cranks: to 3/4 inch are avaiable, billett the best
Rods: stock preped with ARP 2000 and polished rods should hold mild blower motor
Mains: any blower motor gets 4bolt mains.
Your pocket book dictates the brands and the quality.
Bored&Stroked
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392 Hemi - Can you use 426 rods

Post by Bored&Stroked »

Thanks a bunch -- going to pickup my engine next weekend . . . hopefully it is a good one! Do you know if you can run 426 rods -- the NASCAR 7.06" versions on a 392.
57' 392 Hemi -- much to learn!
George
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Joined: Wed Aug 25, 2004 4:12 pm
Location: Fl

392 hemi heads & flow

Post by George »

A good book to pick up is Tex Smiths hemi book. A few errors but over all a good one www.hotrodlibrary.com 1-800-513-8133. heads while the 55 331, & 354 heads flow better than 392s you probably wouldn't notice on the street. Rods 440,426 7426 NASCAR rods can be used, w/ custom pistons and/or crank work. Stroker cranks are used in racing,but I've heard talk of them throwing rods....
392heminut
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Post by 392heminut »

Also, if you use the 440 rods you should get the whole reciprocating assembly balanced as the 440 rods are quite a bit heavier than the stock 392 rods.
Owner of the Poor Man's Hemi Cuda
Moparlee
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Post by Moparlee »

7.06 rods? I thought that the 426 Nascar rod was on .100 longer than the stock 440 rod which is 6.7 something putting the Nascar rod around 6.8 something and the 392 being 6.9. Is this not right?

Lee
392 Hemi
354 cracked and needs a sleeve
241 or 270 the only running one I have
340/E-brock heads/six-pack/4-speed/mini tubed/spool-64 Valiant
Bored&Stroked
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426 Rods

Post by Bored&Stroked »

I saw an add on eBay for some 426 rods that were 7.06 length - said they were a standard part number from Mopar.

Thanks for all the help guys -- will get Tex's book, as he is typically a decent writer. Will probably go ahead and run the 392 heads, unless I decide to "take the plunge" and pickup some aluminum ones. I'd like to save some serious weight and with a blower and all that good stuff, the front end of my Merc is going to be quite heavy. Are any of you guys running the aluminum 354 versions from HotHeads?

Take er' easy . . .

Dale
============================
57 392 Hemi . . . just starting down the path!
2003 5.7L Hemi . . . or so they say . . .
57' 392 Hemi -- much to learn!
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