boostedmonte

Hello all, new here and sorry if I am asking for redundant information, I would just like to do this right the first time. I'm building and reassembling my 5.3l for the swap in my gbody Monte.
My main question is head gaskets. I'm planning on a turbo build with a goal of 650 crank hp. I told my buddy I wanted to go LS9 because thats what I have seen on the forms from what others are working with. He said I would have to resurface the block and the heads when I do this. Is this true?
Thanks in advance for all the help.

G Atsma

As far as the gaskets go, use 'em. No prep needed.

00pooterSS

iTrader: (40)

No you don't have to resurface but it's always good to at least carry the heads to a machine shop to be inspected for flatness. It's cheap if they need a little skim and it helps a lot if they are perfectly flat.

I personally do not like the idea of running a 4.080 gasket on a 3.78 bore, but people do it and it works.

G Atsma

Good thinking! How much is usually removed with a "little skim"? Like .005 - .010?

madmann26

I did a poor mans resurface on a set of 706s in the garage with a piece of MDF and some sandpaper.

So far no issues from it. I was clean, clean, clean about it.

boostedmonte

Is there a different gasket that you prefer? Im open to suggestion. And I had a shop do some head work for me already, putting in springs and what not for my cam, so I can most likely have them check it out for cheap most likely.

00pooterSS

iTrader: (40)

It depends on how far out the head is, but you can do even less than .005 that I'm aware of.

I sometimes use sand paper and lightly sand if I just want to do a light cleanup. But I try to only use razor blades for picking off chunks and cleaning sprays if I can, I get real paranoid about sanding a little too much in one spot and making it not perfectly flat any more.

I like LS9 gaskets, they are great. In my opinion all GM MLS gaskets are great. My personal preference here comes into play with bore size though, putting a 4.080 on a 3.780 leaves .300 (.150 all the way around) of the cylinder liner open, and I like to go for max sealing surface where I can.

But again, lots of people have done the LS9 on 4.8 and 5.3 truck motors and had great luck with it. Essentially, it's the wrong tool for the job but it still gets the job done very well. So is it wrong..?

tech@WS6store

iTrader: (2)

Ls9 gaskets are closer to 4.100 actually.

If you have notched heads they wont work anyway.
Our rpmspeed head gaskets work well and the pair are same price as one ls9 gasket.

00pooterSS

iTrader: (40)

Do you know the exact number? I haven't heard the exact number. That makes the issue even worse.

And that's a good point on the notched heads

tech@WS6store

iTrader: (2)

Exact number? You mean bore size? They are 4.100. And .053ish thick.

00pooterSS

iTrader: (40)

Yeah you said closer to 4.1 so wasn't sure what that meant. Thanks for the info man.

Mavn

iTrader: (3)

I am running the WS6 store gaskets on my 5.3 . I had to Copper coat them to make them not leak water out of the head gasket. Torqued dry with ARP studs and just filling up the block with water it would leak out of the back of the head gasket on both sides . Pulled heads and copper coated both gaskets and now it doesnt leak .

I had the heads milled flat so it's not a warped head problem . Not sure if I got a *faulty* set of gaskets or what. But they seem to be working good now with the copper coat . I have pushed 14# on them with an on3 billet 84/75 with no issues so far .

tech@WS6store

iTrader: (2)

Ive installed quite a few (20 sets) with no issues and we have sold so many sets, honestly you and one other person are the only 2 issues. I would not recommend copper coat though. If they dont seal we will wnty them. But since the whole gasket is coated its not a good idea to put something else on them. Sometimes particles do get in between the mls layers that cause this. Happens on nearly any mls gasket.
I know you said you had issue on our fb page though. Glad you got it done, but next time, we can swap em out.

Mavn

iTrader: (3)

Yeah no biggie. I got it to work. If I pull the heads I'll purchase another set 🤟