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using 6.0 heads on a 346 block?

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Old Apr 20, 2003 | 03:24 PM
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Default using 6.0 heads on a 346 block?

i know alot of people do this but wouldn't the larger diameter chambr cause problems cause it's bigger than the bore??
please enlighten me! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

<small>[ April 20, 2003, 04:34 PM: Message edited by: 1dirtyZ ]</small>
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Old Apr 20, 2003 | 04:30 PM
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Default Re: using 6.0 heads on a 346 block?

Don't..they don't flow better than regular 5.7's AND you WILL loose compression thus lowering ur HP numbers.
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Old Apr 20, 2003 | 04:34 PM
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Default Re: using 6.0 heads on a 346 block?

they're reworked and milled to gain compression.
i'm just worried about detonation or portrusion of the deck edge at the edges of the combustion chamber.
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Old Apr 20, 2003 | 09:15 PM
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Default Re: using 6.0 heads on a 346 block?

I donn't think I've read about anyone running 6.0L heads on a stock shortblock... The port bowls would HAVE to overlap the cylinder walls, and might even lead to head gaskets blowing I would think. Or at least weakened head gaskets.
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Old Apr 21, 2003 | 01:08 AM
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Default Re: using 6.0 heads on a 346 block?

don't some of the sponcers sell them for 346 motors?
and don't alot of the boosted community use them on stck shortblocks to help compression?
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Old Apr 21, 2003 | 07:45 AM
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Default Re: using 6.0 heads on a 346 block?

You're thinking of the 5.3L heads, not the 6.0L.

For boosted apps, I think most of those guys are running resleeved LS1's or iron blocks. Although I think PSJ said he was going to use 6.0L heads on his latest project...

edit: PSJ's setup is going to be close to stock cubes as well.

<small>[ April 21, 2003, 07:46 AM: Message edited by: SMOKINV8 ]</small>
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Old Apr 21, 2003 | 08:19 AM
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Default Re: using 6.0 heads on a 346 block?

Harlan currently runs 6.0's on a 348ci. (3.905 bore)

I am about to do the same thing.

I will be using the 6.0 MLS gaskets.

I will be at 9:1 compression for the blower.
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Old Apr 21, 2003 | 04:00 PM
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Default Re: using 6.0 heads on a 346 block?

thanks colonel,
so are there any issues?
what do others use? (if it helps its n/a)the 5.7 gaskets or the 6.0 ones??

<small>[ April 21, 2003, 04:03 PM: Message edited by: 1dirtyZ ]</small>
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Old Apr 21, 2003 | 04:05 PM
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Default Re: using 6.0 heads on a 346 block?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by JoSeY:
<strong> Don't..they don't flow better than regular 5.7's AND you WILL loose compression thus lowering ur HP numbers. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Huh???? I'm confused. What's your point of reference on this? My head porter, who ports a LOT of heads, gets the best result with 6.0L heads. He's hit over 320cfm with a 6.0L head.... what's the max you've seen on a 5.7L LS1 head? ****, that 320cfm outflows a lot of the Stage-2 LS6 heads.

So.... what's your point of reference?
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Old Apr 21, 2003 | 04:55 PM
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Default Re: using 6.0 heads on a 346 block?

6.0 flowing better then LS6s wow..... Here is a flowsheet of Raughammers LS1s vs LS6 heads.

<img src="http://www.lockon.com/people/photoalbums/images/15714/78/2%2DLS1vsL2%2Ejpg" alt=" - " />
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Old Apr 22, 2003 | 06:00 AM
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Default Re: using 6.0 heads on a 346 block?

Could someone tell me the bore size of a 6L motor?

I will be using 6L heads[GREAT flow numbers] on a stock 346[or just might pull the motor and use a set of Diamond pistons,3.905-348CI].

So,what affect will the larger chamber 6L head have on the smaller bore 346CI or 348CI ?

6L gasket will sit a bit away from the edge of the cylinder bore?Could this cause a problem?

5.7L gasket will shroud the 6L cylinder head?
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Old Apr 22, 2003 | 08:34 AM
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Default Re: using 6.0 heads on a 346 block?

that's what i'm trying to find out.
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Old Apr 22, 2003 | 09:25 AM
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Default Re: using 6.0 heads on a 346 block?

I've got some 6.0L heads on a stock 5.7L. No problems, although, I'm about to take the heads off and put some stock ones back on. One of the sponsors didn't do what they said they did to them, so I have NO compression. Therefore, this car is a DOG. I used a 6.0L gasket from GM. The heads were a mild port job and they flowed 304@.600. They picked up 20cfm when I had the valve job redone, one that a sponsor orginally did. If you can't tell, this sponsor does GOOD work...NOT.
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Old Apr 22, 2003 | 11:30 AM
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Default Re: using 6.0 heads on a 346 block?

so i should go with 5.7 gaskets?
(if so which ones? pre2001 or 2001 and newer??)
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Old Apr 22, 2003 | 09:22 PM
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Default Re: using 6.0 heads on a 346 block?

anyone?
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Old Apr 23, 2003 | 05:58 AM
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Default Re: using 6.0 heads on a 346 block?

So we use 6.0 MLS gasket?

Come on,answer our questions if you know FOR SURE.
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Old Apr 23, 2003 | 09:50 AM
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Default Re: using 6.0 heads on a 346 block?

6 liter is a 4.000 bore STOCK.

Harlan is using GM 6.0 MLS gaskets, he has 6.0 heads on top of a 348ci (3.905 bore) LS1 motor.

I will be doing the same thing.
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Old Apr 23, 2003 | 07:11 PM
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Default Re: using 6.0 heads on a 346 block?

I am using the stock GM gaskets for a 6.0l motor. I have not had any problems.
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Old Apr 23, 2003 | 08:53 PM
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Default Re: using 6.0 heads on a 346 block?

according to that graph, campbell's heads dont even flow 300 cfm untill over .620" lift? whats up with that? .550" lift looks very weak. i am confused?????? <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
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