When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Appreciate the input. I don't' know what a ls9 gasket thickness would be with the phenolic removed. They are .055 untouched. I'll see if I can get a measurement on that specific layer.
Also find it hard to believe they sell .027 thickness gaskets if they would cause instant failures over 5k. In fact... I believe I ran a .027 gasket on a 4.8 many years back. I was looking for more compression because I ran 799 heads on it. And I buzzed that sucker to 7800 quite often. So I think there may be other factors at play there.
Don't the 799s have a larger CC, with valves located a bit further away?
Chevelle, WHY are the pistons on these engines "out of the hole" from the factory?
This is the first type of engine I've messed with that does that. Pretty much all the others were in the hole by at least a few thousandths.
Man I wish I knew the answer to that question. I mean, we’re talking about the thickness of a sheet of paper…ish out of the hole, but it is what it is. Like yourself, all the years I had my hands in SBC’s which were in the hole, and we cut the deck to get to zero. That platform actually worked with .027 gaskets, because the piston was in the hole enough to keep it from hitting. I’m sure the GM engineers had a reason to go this route, I just haven’t asked the right guy so far.
i.
.................................." one recently i did used head gaskets, used stock bolts impacted down, 16 psi and drove"
.
.
.
Impressive "SEND IT"
Did you quite literally tighten LS head bolts with impact wrench ?
How many 'Uggah- Duggahs' did they take ?
Recall the approximate PSI Line pressure ?
I am amazed at how tough these little LS motors are.
Absolute pinnacle of Gasoline engine durability acheived.
4 uggas, milwaukee m18 1/2" impact. did it by feel if that makes sense. it was an interesting experiment, i dont recommend that sort of thing for folks that dont have a lot of engine building experience and a willingness to pull it back apart on a whim
After looking more closely at the LS9's they don't have a definite composite "thick" middle layer to remove. Each layer is roughly the same thickness at .007ish. My digital caliper shows roughly .005 outa the hole.
I did see these as cheap slightly thinner option. .045 and $60ish for the pair. May go that route and cut .100 off the heads and see what happens. Should be about a 45-46cc chamber and 13:48 ish.
May need to overshoot that a bit more since it will be fly cut a ton.
After looking more closely at the LS9's they don't have a definite composite "thick" middle layer to remove. Each layer is roughly the same thickness at .007ish. My digital caliper shows roughly .005 outa the hole.
I did see these as cheap slightly thinner option. .045 and $60ish for the pair. May go that route and cut .100 off the heads and see what happens. Should be about a 45-46cc chamber and 13:48 ish.
May need to overshoot that a bit more since it will be fly cut a ton.
11-30-2023, 05:58 PM
