Fixing a broke LS7
03-13-2021, 07:53 AM
#1
Fixing a broke LS7 I blew up my moms C6 Z06 a few months back and have since gathered parts to build her a heads/cam LS7 so she can drive it this summer.
Now I知 trying to save old the old blown up engine. Exhaust valve in #6 dropped, took out the piston, head and cracked the sleeve at 7k rpm. Shut it down almost immediately and that was the extent of the damage essentially. All bearings looked amazing and dry sump tank barely had any flake in it when I tore everything apart.
A buddy cut the sleeve out for me and we saw where the bore was cracked pretty much all the way down the water jacket. What I am asking is if anyone here knows someone who is willing to try to weld the block up so I can attempt to put another sleeve in it and run it in my V1. If this was an LS1, I wouldn稚 be asking but I知 interested in trying to save this LS7
Derek
Now I知 trying to save old the old blown up engine. Exhaust valve in #6 dropped, took out the piston, head and cracked the sleeve at 7k rpm. Shut it down almost immediately and that was the extent of the damage essentially. All bearings looked amazing and dry sump tank barely had any flake in it when I tore everything apart.
A buddy cut the sleeve out for me and we saw where the bore was cracked pretty much all the way down the water jacket. What I am asking is if anyone here knows someone who is willing to try to weld the block up so I can attempt to put another sleeve in it and run it in my V1. If this was an LS1, I wouldn稚 be asking but I知 interested in trying to save this LS7
Derek
03-13-2021, 08:20 AM
#2
There is a guy on here Steve at RED Performance out of California he is the best at determining that answer and doing the work. He does a lot of the MID sleeve work. I would post a couple of photos or if you get a hold of him send him photos - he will tell you if it can be saved or not.
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Corona (03-13-2021)
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G Atsma (03-13-2021)
03-13-2021, 09:50 AM
#4
TECH Senior Member
03-13-2021, 10:30 AM
#5
03-13-2021, 10:41 AM
#6
http://www.raceenginedevelopment.com/
The sleeves are a bit thin but.. Reasons for keeping a Good Tune and resistance to detonation.
Thin Skin sleeves
The sleeves are a bit thin but.. Reasons for keeping a Good Tune and resistance to detonation.
Thin Skin sleeves
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G Atsma (03-13-2021)
03-13-2021, 01:14 PM
#7
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Lots of people on this site have had issues with the LS7 blocks, cracks in the cylinders and cracks on the decks, bolt holes to water jackets. For the amount of a new one and what people want for used ones I’d consider getting a Gen4 5.3 re sleeved for large bore build. Maybe get 1/2” head bolts done at the same time.
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03-13-2021, 02:18 PM
#8
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Have you ever seen an LS7 block where the main caps are bolted have been ripped away from the sides of the block? I've seen two so far and can only assume it's from throwing too much power at them. If your gonna go big on boost then start looking into better foundations, plain and simple.
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G Atsma (03-13-2021)
03-13-2021, 09:46 PM
#9
There is a guy on here Steve at RED Performance out of California he is the best at determining that answer and doing the work. He does a lot of the MID sleeve work. I would post a couple of photos or if you get a hold of him send him photos - he will tell you if it can be saved or not.
It痴 not the blocks, it痴 the valve guides that cause the valves to break off and THEN the block gets hurt
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G Atsma (03-13-2021)
03-14-2021, 06:58 AM
#10
TECH Fanatic
What were you doing at 7000 RPM in your mother's vehicle . . . somebody else's ride? Sorry son, but you have been written out of the family will and you can go live somewhere else . . . .
Rick
Rick
03-14-2021, 12:23 PM
#11
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....Since your kids didn't work and pay for the ride there's no real appreciation there. Lessons learned and sometimes there tough ones but kudos to your mom for giving you an opportunity to make things right. I would personally scrap the entire short block and seek a better alternative because you owe her that and most likely you'll be driving it again.
03-14-2021, 12:28 PM
#12
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PS. Don't go throwing a band-aid on stock LS7 heads that are known for having guide issues. Buy some new aftermarket ones..GL
03-14-2021, 03:53 PM
#13
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Originally Posted by 01CamaroSSTx
....Since your kids didn't work and pay for the ride there's no real appreciation there. Lessons learned and sometimes there tough ones but kudos to your mom for giving you an opportunity to make things right. I would personally scrap the entire short block and seek a better alternative because you owe her that and most likely you'll be driving it again.
Originally Posted by 01CamaroSSTx
PS. Don't go throwing a band-aid on stock LS7 heads that are known for having guide issues. Buy some new aftermarket ones..GL
You can come breaks my wife's vette too if you want...
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03-15-2021, 01:02 AM
#14
Haha mom is a badass, i put a cam in it for her last year. I already have another LS7 I知 ready to build for her and get her back on the road for spring. I知 not some rich kid, I find deals and I do 90% of my own work. I知 just trying to save this block because it is an LS7, otherwise I would already have measured out what size glass I need for a coffee table!
Last edited by SE-R Spec; 03-15-2021 at 01:39 AM.
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Vette-byrd (03-18-2021)