I am posting this for a friend. He is running a single 96mm (not sure what kind), forged ls1, stock crank, and 317 heads. He wants to know what head gaskets he should go with. He is planning to run around 23-25lbs of boost and is shooting for around 1000rwhp. Could he use a stock GM head gasket? what would you guys recommend? And can the stock LS1 block and crank handle a 1000rwhp?

 

GM LS9 Headgaskets

 

use to be that you would pick up the 6.0 MLS gaskets, but now that the ls9 ones are readily available you can't go wrong with them. I think they are a 7 layer gasket.

 

LS9 period. That's what I run.

 

LS9 gaskets, cheap too.

 

I just put in LS9 gaskets, 12622033. Haven't boosted them yet but they are what was recommended. $90 shipped for a pair from GMPD.

Check the numbers on them before installing, people have gotten incorrect gaskets before.

 

not sure if anyone mentioned ls9's but they are holding up under some serious boost. I know of at least one guy making 22 lbs with twins.

jk

 

ls9s for sure. seen someone copper spray each layer and run around 25lbs

 

I though the bore size would be was too big for a stock cube ls1?? you guys sure you can run ls9 gaskets on a ls1?

 

I'm using them on my 5.3, which has a smaller bore than an LS1.

 

Really? How many lbs of boost?

 

Not boosted yet, but looking for around 15psi. If you search here for LS9 gaskets you will find many 5.3s using them.

 

im running them on my ls1. see as high as 12lbs (19* timing)

 

I didnt know that. I thought the bore size would be way too big for a LS1 or 5.3. Looks like he will be going with ls9 gaskets then. Can they handle 23-25lbs? What can the stock LS1 block handle?

 

I'm running stock gm 6.0l gaskets and stock ls1 block. I've ran 156 mph in the 1/4 at 3500lb, defiently not 1000rwhp but it works.

 

How much boost? What rwhp?

 

Ls9 gaskets here with arp studs stock ls1 block 11lbs

 

Thanks for the replies guys. What can a stock block, stock crank handle? What boost level would lift the heads?

 

Ls9 gaskets here on a filled 6l block making over 1000whp

Coated gaskets with copper

 

Not many ls1 blocks been above 1k that I know of. I have seen a few but just a handful. 1k should be ok if everything has been prepped right and maybe extra precautions taken like pinning mains etc.

Stock crank i have seen many run well above 1k. Should be just fine there

Lifting the heads are all different for people. Some lift and push water at 12lbs and some never even running 25lbs. honestly there are several factors that play in this.... head deck thickness, surface prep, head gasket type and prep, cylinder pressure, and mostly TUNE. We have no way of telling how your friends tune will look but if all precautions are taken then he should be fine. 317's have been to 1k no problem and even so very few have pushed water. Since he is using 317 heads then deck thickness wont change, make sure the surface and trueness across the head is good, and use ls9 gaskets well prepped with copper spray and watch where you touch on the binding surfaces. Also use PLENTY of clamping force...to be had through ARP. At that boost level ARP studs ftw.

Good luck