Glenno108

taking consideration of the weight away, which is better the iron or ali 6 or 6.2 litre blocks?

87silverbullet

iTrader: (11)

In the LS world the bigger the bore the more your cylinder head choices start to open up. For example, with a 6.2 block you can run the Texas Speed PRC LS7 small bore head which requires a 4.065 bore, which you really wouldn't want to do to an iron block because it will make the cylinder walls thin. Those heads will make a ton of power if you decide to stroke the 6.2 out to a 416 or something of that nature. Don't worry about strength, there are guys in the forced induction section that push the alum blocks to 8-9-1000hp. In stock form

Gunslinger09

Iron is stronger. As far as bore size thats what they make sleves for. I have always wanted to make a 4.125 bore X 3.622 stroke 387 CI motor that would breath deep and spin to the stratosphere.

Tainted

iTrader: (9)

Aluminum. Lighter and unless you are boring, there is no advantage except FI or huge nitrous hits.

87silverbullet

iTrader: (11)

I don't see how you can make a blanket statement as far as Iron being stronger. There are guys pushing alum blocks to ridiculous hp numbers are they are still going strong. Skinnies has his 5.3 alum stock block in the 850hp zone and it is a stock long block. Mark Koehler of the ohio boys pushed a stock LS2 block to 1700hp before the sleeve decided to crack in it. IMO either block will be stong enough to hold the power that any one of us would be able to throw at it.

As far as sleeves. Why would you want to sleeve a block to get bore when there already might be a block you can use that already has enough bore. Nobody would want to buy a block to then have to sleeve it unless they want the superdeck from ERL and their stronger sleeves.

KCS

iTrader: (20)

The iron blocks are not too thin at 4.065" bore. The engine in my Trans Am is a 6.0L block bored out to 4.065" and the engine going into my Mustang is a 4.8L block punched out to 4.065", and it still had as much as .300" wall thickness, .220" minimum.

87silverbullet

iTrader: (11)

That is your own engine and I would do the same thing, but I would not tell the masses on ls1tech that it is ok to punch out an iron block that far and then some one throws 28lbs of boost or 250 shot and detonates and it cracks.

I know you know and I know the limitations on these blocks and what we would do to our own motors, but there are alot of guys who don't know so I keep them on the safe side of 4.030-040 on an iron block.

bww3588

iTrader: (49)

I agree, but if the masses take something like this as gospel, that's their own problem. Nobody in their right minds would bore .285 out of a 4.8 block without sonic checking. And if they do, well again, that's their own problem.

CharlieC

iTrader: (5)

Kind of like asking Boxers or Briefs... Just depends, and everyone has an opinion.

Charlie

6D9 Matt

I would stick to aluminum. Seems plenty of people are throwing hella power at them and still doing fine.

Grr

iTrader: (2)

NO, weight is the most important thing. 110lbs is a ton of ******* weight off the front of a car. In a NA app there is no way in hell I would use an iron block again. LS3 is where its at

bww3588

iTrader: (49)

The extra 110 is a worthy trade off to most when it comes to cost.

Grr

iTrader: (2)

but how much would you spend to remove 110# off the car to compensate?
realistically you would need to make another 20-30hp to offset the weight and maintain the ability to 60' like you would with a lighter front axle weight

adamantium

iTrader: (3)

Id take aluminum just for the fact that 110 extra pounds is not something i would want in an already heavy platform. It all depends on the budget you have and what matters most to you.

Tainted

iTrader: (9)

you could always do like the one one guy did not to long ago and polish the oil galley and remove all the excess casting material. that could save maybe 15lbs

Grr

iTrader: (2)

I just get a kick out of it, when I read a build thread they do a LQ4 build or 370 iron build.
Then about 6 months later they are posting up all these pics of tubular k members and a-arms, pulling the carpet, throwing the A/C out, no radio etc.
"OMG i'm under 3400# now with these parts it should drop off 2/10ths!!"

Yup, only cost you $1500+ in parts, no comforts (A/C, sound deadening, carpet etc.) when you could have all that for another $4-500 or so up front to get a aluminum block and maintain the same weight.

My car is 3360# (1860 on front axle) with me in it, and a completely full tank(16 gal). I have a/c, cruise, heat, all the sound deadener, carpet, etc. No comforts have been touched. The difference with an iron block as the only change would be 3470# (1970 on front axle), doesnt seem like much until you type out the numbers

LS6427

iTrader: (2)

This thread is really a waste of time unless you tell everyone what you're gonna use this engine for......what's your power goal?

What's your budget?

And FWIW......I asked the question about weight difference between the two blocks and how it feels for city driving to go to an iron block. I was able to get rides in two Trans Ams that switched to iron.......there is ZERO difference in feel. So if you're going for big power, go iron. 800 RWHP or less, stay aluminum, but you'll need to resleeve an aluminum block which costs like $1,600.

.

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bww3588

iTrader: (49)

That makes no sense. It doesn't take a tubular k member, a arms, and removal of every creature comfort to lose a buck ten off the car.

With the right setup in the front end, you can lose the spare tire and jack, move the battery and not ever notice the added weight, and still shift more weight to the rear on acceleration....for 4-500 less than an aluminum block.

adamantium

iTrader: (3)

I rather be 110 under original weight than over. Its not THAT serious to most, but to me a person thinks every bit counts, its alot.

02sleeperz28

iTrader: (26)

No more stock motor for me and I'm staying aluminum block.