Twins with Twins, Anyone?

MarkBroviak

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May 25, 2008
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This is what I do! Anything 1200hp+ gets o-ringed on the block side and 625s. I've yet to have an issue myself up to the ~1600whp area.
We went to anything over 800hp or twin turbo towing trucks because they are very aggressive on cylinder pressure loading and can cause them to leak. Orings and ARP2000 is better than 625+ without the orings for the in between builds if budget is an issue also.
 
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2004LB7

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Dec 15, 2010
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I was just waiting for one pf those fence poles to wedge right up into the oil pan, cabin or something else important. Just to let them know how stupid they are
 

Bdsankey

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We went to anything over 800hp or twin turbo towing trucks because they are very aggressive on cylinder pressure loading and can cause them to leak. Orings and ARP2000 is better than 625+ without the orings for the in between builds if budget is an issue also.
I wish I'd have o-ringed mine but that ship has sailed. I'm not too concerned on mine but I do agree that o-rings are a great idea.

I've always done ARP2000/MLS up to 800whp area, 625/MLS 800-1200whp, 625/o-ring/MLS on 1200whp+.
 

kidturbo

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Jul 21, 2010
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Concern with that last set of heads, is all these center bolt holes being not round now. Ya can see it better after the cut. From the top, holes look like ya ran a hone down em..
Anyone ever noted that much wear before?
534b92b0cef84cb5612f11d01bfcf39a.jpg


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Bdsankey

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Concern with that last set of heads, is all these center bolt holes being not round now. Ya can see it better after the cut. From the top, holes look like ya ran a hone down em..
Anyone ever noted that much wear before?
534b92b0cef84cb5612f11d01bfcf39a.jpg


Sent from my SM-S901U using Tapatalk
I can't say I've seen that before.
 
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kidturbo

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I sent my buddy that video link. He said they forgot to fished those with a low speed cut. However his old machine still can't get down to 50ra on low. But goal of seeing how warped they are is accomplished.. Time to chat with ARP, cause this engine has now lifted 3 times in 100 hours. While it's twin, is still tight and happy.... ??
 

1FastBrick

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Man, Eric got grey. We havent gotten together in ages.

Yeah, please dont help perpetuate that WhistlingDiesel guy. He's a complete waste of time, even as satire. Makes diesel owners in general look horrible.
I was on my mobile when I upload it and something must have goten switched up. I was wondering about the coments from my post. Any way, I Fixed the link though so you dont have to look at that non sense.
 
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1FastBrick

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Concern with that last set of heads, is all these center bolt holes being not round now. Ya can see it better after the cut. From the top, holes look like ya ran a hone down em..
Anyone ever noted that much wear before?
534b92b0cef84cb5612f11d01bfcf39a.jpg


Sent from my SM-S901U using Tapatalk
By chance, have you checked the block deck for warpage on that engine?

Those are just standard GM heads or did they have porting done on them? LMM or LML. Been so long I forgot.
 

kidturbo

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By chance, have you checked the block deck for warpage on that engine?

Those are just standard GM heads or did they have porting done on them? LMM or LML. Been so long I forgot.
Heads are stock LBZ/LMM castings, no port work. Both blocks originally were decked 0.005. And I checked it with best straightedge bar my buddy had. Which wasn't far off on from what the mill cut off in pics above. So I feel the block is fine, unless it's cracked. Next weeks job, magnaflux the deck assembled..

I'll share some bore scope pics of those bolt holes when I pick up those heads later this week. I don't recall them being like that when we bolted them on. So these heads were clearly moving around enough in less than 100hrs to oblong all the holes.. Our high mileage spare castings look fine. Did I get those from you?? I only recall they were Seasoned, having like 5-700k or something..
 

1FastBrick

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Heads are stock LBZ/LMM castings, no port work. Both blocks originally were decked 0.005. And I checked it with best straightedge bar my buddy had. Which wasn't far off on from what the mill cut off in pics above. So I feel the block is fine, unless it's cracked. Next weeks job, magnaflux the deck assembled..

I'll share some bore scope pics of those bolt holes when I pick up those heads later this week. I don't recall them being like that when we bolted them on. So these heads were clearly moving around enough in less than 100hrs to oblong all the holes.. Our high mileage spare castings look fine. Did I get those from you?? I only recall they were Seasoned, having like 5-700k or something..
Not from me.

I was curious because I have heard of the guys with ported factory heads having issues with them warping and cracking because the casting is thinner after porting.
 

kidturbo

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Garrets best friend, is one of em who suggested I use that $75 a bottle block/ head sealer I'm now trying to clean off all our powder coated pieces.. Those guys all swore by it for sealing up Six Leakers, and others stuff they were attempting to kill. However, when she split the welds in the reservoir tank, that $150 worth of magic sauce, is now JB weld sprayed over all the pretty pieces... Not to mention all of it sill in the block.. Guess it's not designed for GM engines..
 
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