how big can you make one?

z06corvette427 · Post by **z06corvette427** » Tue Sep 02, 2003 12:34 pm

does anybody know how big you can make one of these new hemis. How much cylinder wall do they have? I was wondering if you could bore and stoke one of these new ones to make it into a 426 or atleast another nostalgic number like 392.

Hemidakota · Post by **Hemidakota** » Thu Sep 04, 2003 5:42 pm

z06corvette427 wrote:does anybody know how big you can make one of these new hemis. How much cylinder wall do they have? I was wondering if you could bore and stoke one of these new ones to make it into a 426 or atleast another nostalgic number like 392.

You can puchase a 528 crate hemi from a local speed shop that deals in Mopar Products. I don't know for sure if the 6.1 Hemi is the same block. We have to wait and see at the next auto showing.

Post by **scottm** » Fri Sep 05, 2003 7:32 am

I have heard that these new Hemi blocks
are not designed to be rebuilt after death.
If that is true, I imagine they cannot have
any boring done to them. We will have to
see if the 6.1 uses the same block or not.

mnc2886 · Post by **mnc2886** » Fri Sep 05, 2003 11:19 pm

Do you know by any chance what the miles per gallon is on the 6.1. I wont expect too much if it is just bored out, or a little bigger stroke, but a new block might be nice. Maybe one that is a real hemi, not a semi-hemi.

Hemidakota · Post by **Hemidakota** » Mon Sep 08, 2003 8:41 am

It maybe true. Someone from Hughes purchased a wreck truck (new one) and seen the bore liners are very thin. Not much to rebore with though.

May hve to talk to Hughes on that one.

6.1ltr and the 5.7 are almost the same minus 1-2mpg. That is not the issue though when buyin large engines.

MG42pillbox · Post by **MG42pillbox** » Mon Sep 08, 2003 4:20 pm

True that is not an issue, But with only .4L of more displacement there must be more than just that to give it that much worse gas mileage. Will it have the same compression and cam?

Hemidakota · Post by **Hemidakota** » Fri Sep 12, 2003 7:49 am

MG42pillbox wrote:True that is not an issue, But with only .4L of more displacement there must be more than just that to give it that much worse gas mileage. Will it have the same compression and cam?

Compression yes (9.6:1) but cam no. It will have a larger torque than the current flat line torque in the 5.7.

MG42pillbox · Post by **MG42pillbox** » Sat Sep 13, 2003 12:03 pm

they need to just cut the BS and Bring back a Big block. 426!!!!!

panic · Post by **panic** » Sat Sep 13, 2003 2:59 pm

MG42pillbox · Post by **MG42pillbox** » Sat Sep 13, 2003 3:15 pm

Good to see your keepin up, kinda.... (but the 392s are hardly Old compared to others. They were a very capable and advanced Motor in the mid & late 50s.....

mnc2886 · Post by **mnc2886** » Sun Sep 14, 2003 7:35 pm

I agree, old 426 hemi in a sport truck and car. And a big block, not a small block bored or stroked to that. I want a big block damnit!!!

Hemidakota · Post by **Hemidakota** » Mon Sep 15, 2003 7:55 am

mnc2886 wrote:I agree, old 426 hemi in a sport truck and car. And a big block, not a small block bored or stroked to that. I want a big block damnit!!!

Asked yourself why they didn't bring back the old hemi 426?

1) Could not pass today's SMOG standard
2) NOt as efficent in design as today's hemi engines.
3) The next big block is currently being tested and it produces more power than the old hemi for a production vehicle.

mnc2886 · Post by **mnc2886** » Tue Sep 16, 2003 8:32 pm

You know what I mean, I want a 426 with the new tech stuff. That would be bad butt.

z06corvette427 · Post by **z06corvette427** » Thu Sep 18, 2003 3:47 pm

Someone needs to make a aftermarket new hemi small block with more material much like World Castings does with their Chevy-based Merlin BBs and Motown SBs. The hopped-up big-inch smallblocks are the trend in streetmachines due to their lighter weight. Can you imagine a 390+cid new fuel injected smallblock hemi in an old 'cuda. That would be incredible! I'm sure it wont happen for quite a few years though, and thats only if the crate 5.7s and 5.7L aftermarket parts actually catch on and they can keep the cost down.

Hemidakota · Post by **Hemidakota** » Thu Sep 18, 2003 4:14 pm

If I stand correct, the biggest you can stroke this crate motor is a 408 size.

Hemidakota · Post by **Hemidakota** » Thu Sep 18, 2003 4:15 pm

mnc2886 wrote:I agree, old 426 hemi in a sport truck and car. And a big block, not a small block bored or stroked to that. I want a big block damnit!!!

Isn't the top Merline engine is a 6XX cube motor? However, not a hemi though. N/A is 7XX HP with 10.1 compression.

MG42pillbox · Post by **MG42pillbox** » Sun Sep 21, 2003 1:07 pm

Yea what about that GM, much rather have a 500 Wedge

z06corvette427 · Post by **z06corvette427** » Tue Oct 07, 2003 1:18 am

the merlins are based off the big blocks and yeah i think their biggest is a 632? cid....the motowns are based off of smallblocks and their newest is a 454 "smallblcok". I like the idea of making the factory blocks stronger with some more material for increased displacement. I wish somebody would recast some of the mopar blocks for the hardcore builders like World Products does. maybe cast some beefed aluminum blocks?

MG42pillbox · Post by **MG42pillbox** » Tue Oct 07, 2003 1:21 am

z06corvette427 wrote:the merlins are based off the big blocks and yeah i think their biggest is a 632? cid....the motowns are based off of smallblocks and their newest is a 454 "smallblcok". I like the idea of making the factory blocks stronger with some more material for increased displacement. I wish somebody would recast some of the mopar blocks for the hardcore builders like World Products does. maybe cast some beefed aluminum blocks?

Well do the 800 ci Keith Black blocks count?..... It all depends on how much you want to spend.... For every American Racing Application, Mopar has their foot in the door and as always are ahead of the game.

panic · Post by **panic** » Tue Oct 07, 2003 8:47 am

MG42pillbox · Post by **MG42pillbox** » Wed Jan 28, 2004 2:23 am

panic wrote:This might be a good time to define the terms. As to geometry, none of the motors mentioned (392, 426, 4.7, 6.1) are hemi. All the chambers are partial sections at best. The modern engine closest to a true hemi is the 1957-71 Harley Sportster.
The new (6.1, etc.) "hemi" motors do not use the spherical-section model at all. It's called a hemi because the factory thinks you'll buy it. In terms of chamber design it's as much a hemi as it is a Toyota (or as a Toyota is a hemi).

(picture from Gary Pavlovich's 318 poly race motor sight: http://www.1962to1965mopar.ornocar.com/poly318.html)

The theoretical advantages to hemi chambers (low intake port down-draft angle, low surface to volume ratio) date to pre-WW2, and are not efficient compared to modern shallow high-swirl quench multi-section chambers, which is what every current design uses.
No designer would give up the advantages mentioned to mimic an obsolete concept.
Th 6.1 has closer bore centers than a 318 (4.09" vs. 4.46"), in fact smaller than any other American V8 including the Buick 215", and lower deck height (9.09" vs. 9.60"), so its maximum size is considerably smaller than the LA motors.

Its no where near a full SPHERE Thats the whole point,...... (sigh) the 66 426 Hemi is less of a Hemi than the 392, the 2003 Hemi is just as much HEMI as the 66,...... What difference does it make if it 100% Hemi like the mid 50s 392 or 95 or so % like the 66 426........ It makes a full "SPHERE" <--- Key Word....... If the new Hemi isnt a real Hemi neither is the 66 426,...... But it is a real hemi....

How hard is this to uderstand.

Whats the point of people trying to denounce the fact,..... The Motor deishgn is the most powerfull Automotive engine of all time either way, what difference does it make.

panic · Post by **panic** » Thu Jan 29, 2004 8:29 pm

MG42pillbox · Post by **MG42pillbox** » Thu Jan 29, 2004 9:24 pm

panic wrote:"Whats the point of people trying to denounce the fact,..... The Motor deishgn is the most powerfull Automotive engine of all time either way"
Compared to what?

I think you have a different understanding of what the words "denounce" and "fact" mean than the rest of the world.

Is this how you win most of your arguments?
1. be wrong
2. repeat your original contention continuously (as if accuracy was a cumulative process)
3. finally the other side realizes that you just don't understand why what you're saying doesn't work
4. they give up
5. you win

Be wrong??? Ok I guess you have a long way to go, but anyway.... Do you think I was attacking you? Im talking about the fact that people call the Magnum 5.7 a half hemi,.... and Im sorry but the 4.7 is not a Hemi

panic · Post by **panic** » Fri Jan 30, 2004 5:53 pm

MG42pillbox · Post by **MG42pillbox** » Sat Jan 31, 2004 3:27 pm

panic wrote:Sorry, the 4.7 reference was a typo on my part, used the wrong picture etc.
"Denounce" does not refer to a dispute over physical properties, physics or dimensions. It is an attack on the character, behavior or motive of another person.
I should not have been quite as vehement.

Just as long as the perspective is understood, it happens. No big deal

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how big can you make one?

how big can you make one?

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