LS7 Block
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Teching In
Joined: Jul 2017
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From: Central Ohio
LS7 Block I have a new LS7 block that I bought pretty cheap. I want to make 1k at the tires and now I find out that many don't like that block. This will be a alcohol twin 61/62 turbo build. The car is extremely light weight and wont need big power to go fast. Its a race only car. Could I fill the block solid or have sleeves put inside the factory sleeves? I will be running LS7 heads also so I will need a fairly big bore. Just checking to see if anyone has tried this with any results. Thanks
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Joined: May 2009
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From: over dere
The weakness of the ls7 block is overplayed. Some guys have had issues but so have a lot of other blocks. But it is better as an NA block
Those things are worth money. You could sell it and buy a darton sleeved 5.3 block and be better off though IMO
Those things are worth money. You could sell it and buy a darton sleeved 5.3 block and be better off though IMO
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Joined: Mar 2018
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From: australia brudda
I have a new LS7 block that I bought pretty cheap. I want to make 1k at the tires and now I find out that many don't like that block. This will be a alcohol twin 61/62 turbo build. The car is extremely light weight and wont need big power to go fast. Its a race only car. Could I fill the block solid or have sleeves put inside the factory sleeves? I will be running LS7 heads also so I will need a fairly big bore. Just checking to see if anyone has tried this with any results. Thanks
I think an LS7 can be made to be just as strong as a sleeved 5.3, 6.0, etc.
The weakness in the factory block is the sleeve material and design. By replacing the factory press-in sleeves with a Darton sleeve that is made from better material, you gain the same strength as you would with the same sleeve in a 5.3/6.0/etc. block.
Call Steve at Race Engine Development and he can tell you all about it. (760) 630-0450
The weakness in the factory block is the sleeve material and design. By replacing the factory press-in sleeves with a Darton sleeve that is made from better material, you gain the same strength as you would with the same sleeve in a 5.3/6.0/etc. block.
Call Steve at Race Engine Development and he can tell you all about it. (760) 630-0450
The point is he can sell the $3000 ls7 block and buy a $1000 ls2 block if he’s just going to sleeve it.
The sleeved 5.3’s are the absolute strongest, but lose significant power at high rpm due to the lack of bay to bay breathing.
The sleeved 5.3’s are the absolute strongest, but lose significant power at high rpm due to the lack of bay to bay breathing.
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Joined: Aug 2009
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From: Coast of San Mateo County Between Pacifica & HMB
I think an LS7 can be made to be just as strong as a sleeved 5.3, 6.0, etc.
The weakness in the factory block is the sleeve material and design. By replacing the factory press-in sleeves with a Darton sleeve that is made from better material, you gain the same strength as you would with the same sleeve in a 5.3/6.0/etc. block.
Call Steve at Race Engine Development and he can tell you all about it. (760) 630-0450
The weakness in the factory block is the sleeve material and design. By replacing the factory press-in sleeves with a Darton sleeve that is made from better material, you gain the same strength as you would with the same sleeve in a 5.3/6.0/etc. block.
Call Steve at Race Engine Development and he can tell you all about it. (760) 630-0450
LS7 Block at a premium and buy a less expensive 5.3 pocketing the
difference. The cost to machine and sleeve I believe is the same and
Steve @ RED (the only place I would have that done) may have 5.3
block in stock and save shipping the LS7 to RED.
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Joined: Aug 2009
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From: Coast of San Mateo County Between Pacifica & HMB
Steve can also put bay windows in by drilling I believe,
depends on RPM,best to discuss with Steve.
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I recently emailed Steve about his blocks. He said the hole in the cam tunnel still gives up power vs an ls2, even with a vacuum pump. Steve is also unable to source 5.3 blocks anymore.
I think with a vacuum pump and the hole in the cam tunnel the hp difference has to be damn small. Steve said as a direct comparison the sleeved 5.3 w/o the breaker hole vs ls2 will be 20+ hp at high rpm with
His favorite setup is a dry sleeved ls2.
I think with a vacuum pump and the hole in the cam tunnel the hp difference has to be damn small. Steve said as a direct comparison the sleeved 5.3 w/o the breaker hole vs ls2 will be 20+ hp at high rpm with
His favorite setup is a dry sleeved ls2.
But at the 1,000 HP level, I'd seriously consider my other options since this is not a "cheap" build by any means. At that point, I think I'd give up the 110 or so pounds and run an iron block. Like a LSX or Dart.