rkreigh

with all the fancy welding technology wouldn't it be possible to weld or machine and bolt on some "add on ears" to a factory block to create a 6 bolt block. isn't that essentially what superdeck does?

I would love to run the 6 bolt heads with a boosted motor but the price of the RHS and other aftermarket blocks with the many expensive parts makes me want to come up with a more affordable solution.

the other "more elaborate" idea would be to machine a steel "deck plate" that that has the extra "ears" machined, and use a set of longer liners in the block and the head bolts to hold it down. again, this is similar to the superdeck technology so not a new idea.

guess the answer might be "write a big check to superdeck" but I'm looking for alternatives.

prefer a 6 bolt aluminum block to keep the balance on the c5 z06 intact.

ERL has the nice technology, just looking to graft on the additional 2 mounting pads for the cyl head bolts and stay with a factory sleeve at a reasonable cost

after seeing the guy cut up LS blocks to make a V12 this should be a snap!

anyone interested?

stevieturbo

Anything is possible. But all the things you propose involve lots of skilled labour and machining.

By the time you've fucked about doing that, you could have just bought a 6 bolt block in the first place, which will ultimately be better than any welded part.

The question is...do you really need it ?

A cheaper alternative would simply be CA625 studs or upgrading to 1/2 studs.

oscs

iTrader: (19)

At what point is a 6 bolt or 1/2" head stud required? I know there are plenty of variables but I see guys running around at 20-23psi on "stock" platforms

stevieturbo

It really is a huge variable.

I think it's a fairly general opinion that sub 1k normal 4 bolts are fine.

Over and above that is where the variables really come into play.

Chicago TDP

iTrader: (3)

There was a build on here that had ears welded to the head...they broke off in the end...

elkydragger

iTrader: (7)

On an aluminum block, you will reach a point where you will need the support in the upper cylinder liners before you need 6 bolt heads. The point of the ERL blocks is the bridge support between the cylinders and the heavy liners. The short of it, if you are lifting arp studed aftermarket thick deck heads, you have probably already cracked a liner.

mike13

iTrader: (27)

Iron block, thick deck aftermarket heads and 1/2" head studs will get you to 1200rwhp on a safe tune.

oscs

iTrader: (19)

Yeah that sounds like a good rule of thumb. The reason why I ask is because id like to see a 1k dyno sheet on my twin 370 build some day. I imagine it will take quite a bit of boost to get there and obviously the more boost you run the more strength you will need.

stevieturbo

Not strictly more boost.

The closer you push the limits of the fuel and compression towards detonation...that is where the risks mainly lie.

If you ran 8:1 I've no doubt you could easily run 30psi boost all day long to make the power and do it very safely.

If you run 10:1, you might do it on 20psi, but you could easily be on the ragged edge of risk.

So it's a combination of factors. Boost in itself isnt the killer.

oscs

iTrader: (19)

Makes sense, I went with 9.1:1 on my motor. I should be able to cram quite a bit of boost down it at that CR

mike13

iTrader: (27)

a friend of mine makes 1000rwhp on a forged 347 aluminum block with thick deck heads. Key is staying away from detonation.

JAX04

iTrader: (17)

Torque....

stevieturbo

Torque can be a killer for sure if enough is made at lower rpm's

But torque is also fairly easily managed via boost control if it is capable of making lots.

rkreigh

thanks guys. I think at this point I'll just go with 1/2 studs and pin the mains

any benefit to billet main caps? I probably won't go much beyond 6500-7k rpms so I'm hoping the stock caps are plenty strong enough.

I will be running e85 on a conservative tune to stay far away from detonation.

I'll happily sacrifice a few ponies for durability as I drive the car often and occassionally on long trips (which is why the flex fuel sensor is so critical to run pump gas on low boost for just croozin around and e85 when set on kill)

the "feasibility" is what I was looking for and it goes a long way towards explaining why ERL superdeck blocks are expensive (not saying that it's not a fair price, they do some pretty extensive mods)

good tip about the "block webbing" for better liner support that's a key advantage to the superdeck block.

I'm trying to "salvage" my LS6 block and make it live as I'm hesitant to run the iron block in the vette and 1000 hp will be more than enough for me for now

but I do have a spare 4.8 iron block lying around that I was thinking about this kind experimentation. I know welding cast iron is pretty tricky, so I considered a "wide block" approach to adding the block ear which would have enough material to use 4 small cross bolts to hold the "ear" onto the side of the block and allow enough room for a stud to for the additional 2 head bolts.

sounds like the consensus is "save your money and buy the block done" or set a more reasonable and save 1,000 hp goal.

thanks for indulging my engineering ideas.

stevieturbo

Probably no need for billet caps at all.

But if going to the effort of pinning....will the billets really cost that much more ? $400 + line bore cost ?

Isnt a huge amount really, plus it's a little extra strength

dschmittie1

iTrader: (64)

I have pinned stock main caps in my LS2 I was told billet main caps are no stronger than a pinned stock main cap. And it only cost me $200 to get my mains pinned

playtoy

iTrader: (5)

From my understanding LME welds on the tabs to the block for a 6 bolt setup.

mike13

iTrader: (27)

I know LME will do it for heads.

stevieturbo

poor mans 6 bolt = just build a good 4 bolt and save your money then buy a proper 6 bolt if you really really need it.

mike13

iTrader: (27)

yep, there are no cheap options.