Inspector12

iTrader: (29)

Cool GL! I have done 1/2 studs done on one of my motors, but I don't think they were any better than the APR 2000 or L19 Ive used. When you say O-ring are you talking about the stainless wire in the heads or old school or what? Ive used the LS9's with good luck, but the last time it was just LS7's because of the bore size etc...

Bobsmyuncle

iTrader: (32)

1/2" studs and just a single oring will hold well over what the op wants. We have a Ysi car making over 1k on an aluminum ls2 w stock sized head bolts and cometics. 21psi. I don't see why 1/2" studs and a single oring on an iron block wouldn't hold 1400-1500 and 30 psi.

qqwqeqwrqwqtq

From my experience, 30ps and 1500hp would create quite a problem for a 4-bolt setup with a single o-ring and copper gasket. I've seen so many of those setups leak I would personally not run one at any HP level.

4-bolt with LS9 gaskets is good to 1200hp +/-. I'll report back if I get one to push water. (wouldn't think twice about using LS9's and ARP studs for the OP's goal of 1000rwhp).

Above that my preference would be 6-bolt/MLS to say, 1500hp.

Above that, 6-bolt/double o-ring. LME set up Andy's motor (7.52/194mph) with dry deck/double o-ring on his LSX block and it's been perfect.

The above figures are based off of my experience and assumes the tune is on, octane is sufficient and you have an efficient turbo system.

As for adding lugs to an iron block, I wouldn't do it. If I was targeting a horsepower level that required 6 bolts per cylinder I would buy a 6-bolt block and that would probably one of the cheaper parts of the build.

stevieturbo

Impossible.

The weld will only be along the outer boundary of the material added.

A fully cast piece will be solid over it's entirety. The welded piece cannot be as strong let alone stronger.

it's also why some high tech stuff in aircraft and even many cars nowadays is bonded as opposed to welded. The bond adheres to a much greater surface area and is stronger than bolts, rivets or even welds. The weld itself may be strong, but as it's only secured to a small area, this area fails first.

Bobsmyuncle

iTrader: (32)

so ur saying with 1/2" studs, ls9's and oringed.... u wouldnt even trust?


but then u say that ls9s with just four stock bolts will hold 1200whp........

im not makin any sense outta this

qqwqeqwrqwqtq

I've not seen an o-ring used with MLS, I assumed you meant copper.

1/2in studs and LS9's are great, not sure of the specifics on how an o-ring would be used with a non-malleable gasket.

Bobsmyuncle

iTrader: (32)

i was under the impression that ppl did it pretty regularly. i knoiw i see it all the time in the bmw, honda, dsm worlds.


the specs on the rings would defanitly be different. i know whenever they use them with mls, there is alot less interferance(if u will). the cummins guys do it too.

Bobsmyuncle

iTrader: (32)

http://m.modernhemi.com/forums/showthread.php?t=1271678

post #4

Inspector12

iTrader: (29)

I'm with ya Jim, but LS9 aren't big enough for a 427 lol! But perfect for 408's like the OP.

LS6427

iTrader: (2)

My builder says I'll have no issues as long as he uses the bigger studs, he's built many high HP FI engines. I was just going to do this additional mounts idea if it wasn't a big deal....seems like it is.

Maybe I'll just o-ring since thats no such a big deal to do. I like a little extra assurance, not being on the edge.....

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LS6427

iTrader: (2)

So its either o-ring + 1/2" studs........MLS gasket

OR

1/2" studs and LS9 gaskets........and no o-ring

Is that the two choices?

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Inspector12

iTrader: (29)

Look Jim and I are telling you to use LS9 gaskets and either L19 or ARP 2000 material head studs or a 1/2 head stud. I don't care for the 1/2 although they have the same clamping strength as L19's. 1/2" studs are cheaper, but about the same price after you factor in the machining the block for 1/2" head studs. The ARP 2000 do have a little less clamping capability, but it is so minimal that it has worked great for me. So since having done both I just prefer to buy the studs in ARP 2000 or L19 IMO. And not doing O-rings!

beavis

iTrader: (15)

HKE is building my LQ4/9 402 and I've ask alot of these question to Erik. He told me that he wouldn't use 1/2" studs that they distort the block. He said that he doesn’t use o-rings until the 2k rwhp. He said it all comes down to the tune but with a good one 1500rwhp is possible on 4 bolt heads. My build consist of Trick flow 235’s, LS9 head gaskets and ARP 234-4317 head studs. I told him I wanted a motor capable of 1200rwhp.

LS6427

iTrader: (2)

Thanks....gotcha....

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LASTLS1

iTrader: (7)

Listen to him or waste your money. I've tried all the set ups you have listed.

Bobsmyuncle

iTrader: (32)

i think 50% of this decision is up to what heads ur buying.

aftermarket heads: no oring, ls9s and studs
stock casting: oring, ls9s, studs

stock heads with studs and ls9s dont usually last past 900-950hp, they can, defanitly, but not usually

LS6427

iTrader: (2)

I think I decided on the AFR 225...thicker deck.

.

cjmatt

iTrader: (4)

The one thing Im wondering though is how you get to the inner topmost boltholes. On the 6 bolt stuff you torque them down from the valley, but you cant get to it on an iron block

87silverbullet

iTrader: (11)

AFR hasn't made a 225 in 2 years. I still think Jegs and Summit still have some left over ones. I talked to Tony Mamo and he said they haven't casted one in a little over 2 years.

Vetal

iTrader: (3)

What about welding for extra bolt holes to aluminium LS1 and Patriot heads? Labor is cheap here compared to what new block/heads would be (add shipping and taxes).