LS7 gaskets not good for iron block and boost
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LS7 gaskets not good for iron block and boost Well I pulled the heads to swap in the LS9 head gaskets, and I did confirm that the LS7 gasket, does not match the coolant ports on a 6.0L iron block. This obviously is not good, and may have contributed quite a lot to the fact that I pushed water every time it has been on the dyno. Even with a mild tune.
LS7 gasket on 02 LQ9 block....
Old 6.0L gasket fits much nicer....
LS7 gasket, note the black area on the bottom where it was pushing water,
The new gaskets will be here tomorrow, and I will compare the LS9 gaskets.
LS7 gasket on 02 LQ9 block....
Old 6.0L gasket fits much nicer....
LS7 gasket, note the black area on the bottom where it was pushing water,
The new gaskets will be here tomorrow, and I will compare the LS9 gaskets.
Why would you put it on there in the first place? Did you not think to check any of this?
Why would you burn money on factory gaskets instead of getting aftermarket gaskets?
Why would you burn money on factory gaskets instead of getting aftermarket gaskets?
The overall success of using GM MLS gaskets!
Readily available!
Just do some searching
https://ls1tech.com/forums/forced-in...s-results.html
https://ls1tech.com/forums/forced-in...igh-boost.html
Dont come in his thread and make it look like he is stubborn for using a stock gasket
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The LS7 gaskets were recommended by Rich at WCCH to go with the heads to unshroud the combustion chamber and valves. It was my fault I didn't catch the blocking of the coolant ports, I accept that.
I had wasted $150 on cometics before, when it was a NA stock 6.0L with milled heads. 3 1/4 mile passes and 3 dyno pulls, when I pulled it down to build the turbo engine, there was evidence that they were leaking coolant, and not anywhere the same area as where they push water now. The GM MLS are proven performers under boost, as long as you get the right ones for the application.
The purpose of this thread was to confirm that the LS7 gaskets do not work with non LS7 or LSX blocks. There was not a whole lot of info on this subject, and some say it didn't work and some say they use them just fine, now here is some photographic proof that there is a blockage.
Last edited by veee8; Feb 4, 2009 at 09:22 AM.
Chill out there man. Thanks for letting us know. It may end up aiding someone on here in the near future. That sucks it happened. Did any thing internally get messed up? No hydro locking or anything?
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I just don't want anyone coming in MY thread and cluttering it up with BS.
No damage, it ran just fine, it would consistently push water with boost levels above 12 psi or so. Standard ARP studs and very conservative timing. They may work OK in a NA application, although I can't imagine it being good to have half the coolant holes blocked, but not the hot ticket for boost. They are only 3 layers too.
No damage, it ran just fine, it would consistently push water with boost levels above 12 psi or so. Standard ARP studs and very conservative timing. They may work OK in a NA application, although I can't imagine it being good to have half the coolant holes blocked, but not the hot ticket for boost. They are only 3 layers too.
I think the why did you check it comment is fairly reasonable. Even if someone recommends something it is always best to double check it. More so since you are mixing parts from two different generations.
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Ok from the pics it looks like they are partially blocked on the top but line up on the bottom ports? Why would partial blockage make it push water?
What heads are you running?
So 12psi or so it started pushing? What max timing you said conservative but what max and do you run alc or meth..what afr?
So the ls9 should work with my afr 225s.I was going to go cometic but did hear some problems with them. My block is prepped to use cometic if I choose it sounds like.
Not sure what other factory mls works with my afr 225 and 408 iron block. How much are the ls9 and are they now readily available?
I have not going past 7.5 psi but was for sure planning to likely in the coming season.
So it only pushes on the dyno not the track or on the street?
And if they don't line up top too good but still seem not totally blocked why do they seem to be pushing water at the bottom where the holes do seem to line up or is that just the picture?
Sorry about all the questions but sure someone did tell me they were running the ls7 with afr 225 heads like mine on their iron block no problems to like 20psi.
Have to dig up that old thread or pm. Still of course if the ls9 fit better and are 7 layer they are a better choice and of course they are already designed for boost applications.
What heads are you running?
So 12psi or so it started pushing? What max timing you said conservative but what max and do you run alc or meth..what afr?
So the ls9 should work with my afr 225s.I was going to go cometic but did hear some problems with them. My block is prepped to use cometic if I choose it sounds like.
Not sure what other factory mls works with my afr 225 and 408 iron block. How much are the ls9 and are they now readily available?
I have not going past 7.5 psi but was for sure planning to likely in the coming season.
So it only pushes on the dyno not the track or on the street?
And if they don't line up top too good but still seem not totally blocked why do they seem to be pushing water at the bottom where the holes do seem to line up or is that just the picture?
Sorry about all the questions but sure someone did tell me they were running the ls7 with afr 225 heads like mine on their iron block no problems to like 20psi.
Have to dig up that old thread or pm. Still of course if the ls9 fit better and are 7 layer they are a better choice and of course they are already designed for boost applications.
Ok found one guy in past posts running ls7 on his iron block with afr heads like mine. Emailed him to see what results he had but also did remember at least one other guy running ls7 with pretty high boost but forget now if it was iron block.
So for anyone else reading this ,any of you guys running the ls7 on iron block to say 20psi with no water problems? Not trying to hijack the thread just trying to gather a bit more data. So what is bore side of ls9 gasket and what is thickness? And now come think see it saying it is four layer or something but its listed as 7 layer?
So for anyone else reading this ,any of you guys running the ls7 on iron block to say 20psi with no water problems? Not trying to hijack the thread just trying to gather a bit more data. So what is bore side of ls9 gasket and what is thickness? And now come think see it saying it is four layer or something but its listed as 7 layer?
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They are L92 heads, it pushed water at 12* timing. Haven't been able to hold it for more then 10 psi on the street due to ZERO traction with the old tires. I haven't tried with the new M&H Drag Radials yet. The dyno pulls only lasted 1.5 to 2.5 seconds, so I imagine it would have been even worse at the track.
I am not saying the blockage caused the pushing of water, but I know it can't be good. The problem is I was relying on what was suggested and claims by others that it should work, in my opinion it didn't, so I had to yank the heads and swap gaskets, at least now, I have a proper fitting gasket, and if it still pushes water, I will chalk it up to the factory L92 castings, and look to do something different.
I am not saying the blockage caused the pushing of water, but I know it can't be good. The problem is I was relying on what was suggested and claims by others that it should work, in my opinion it didn't, so I had to yank the heads and swap gaskets, at least now, I have a proper fitting gasket, and if it still pushes water, I will chalk it up to the factory L92 castings, and look to do something different.
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I am going to pick up the LS9's right now, I will report back shortly.
I am all for trying get the data out there, that was the problem when I got mine, there wasn't any conclusive evidence that they wouldn't work. I still can't believe I didn't catch it before I put the heads on.
I am all for trying get the data out there, that was the problem when I got mine, there wasn't any conclusive evidence that they wouldn't work. I still can't believe I didn't catch it before I put the heads on.
Ok your timing was pretty low but what is your compression? And yeah maybe l92 heads will push water more than say my afr 225s. Do you have head studs also?
So to repeat what is bore and thickness of the ls9 head gaskets?
So to repeat what is bore and thickness of the ls9 head gaskets?
Sorry another question. Your dyno runs are on e85? If so does that affect timing or is 12 still considered low timing even on e85? We don't have e85 option up here yet so dont' know much about it.
Question does e85 cause any different cylinder pressures or something? It is great how clean an engine running ethanol looks. I sure wish we had the e85 option but it might be years till we see it up here. It does seem to be the HOTNESS for FI cars.
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I had problems with lifting before I switched to E85.
A quick wipe of the pistons, and the little bit of "carbon" on the pistons came right off.
I have the gaskets in my hands, they are nice, they are silver instead off the gold color. They are a 7 layer, with 4 steel thick layers, and 3 thinner black filler layers. The bore is 4.100"
A quick wipe of the pistons, and the little bit of "carbon" on the pistons came right off.
I have the gaskets in my hands, they are nice, they are silver instead off the gold color. They are a 7 layer, with 4 steel thick layers, and 3 thinner black filler layers. The bore is 4.100"
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My reasoning is these were developed for forced induction. If 5 would have worked why did they come out with the 7? They are stamped 6.0L/6.2L on the gasket.