ovaltobowtie2

Im about to begin a build and I see people contiplating all kinds of different cube possibilities. If you are going over 400, why not just go as much as you can?? People talking about 402,408,414 etc....Is there a reason why some of you guys arent going straight to the top and doing as much cube as possible?? Is it rod angle, clearance issues....what?

1QuickT-A

iTrader: (12)

Most of the people with 408's do not want to use the aluminum block with sleeves.. Cast iron blocks are stronger and cheaper to build. Look at how many people have had problems with cracked sleeves, leaking sleeves, sleeve installations, etc. You dont have to worry about any of that with a cast iron block..

mnc2886

A 408 is much cheaper than a 427. It will also hold nitrous alot better. Besides, I've seen hydrolic roller 408's with 550+ hp and 520+ tq so, the numbers can be there. Check out VINCE. His 408 is bad ***. Futral seems to have found their specialty.

Demon SS

iTrader: (3)

one reason is cost also, I can build you a "budget" 408 shortblock for around $3800.00. a "budget" 427 shortblock will run about $5900

Steve - Race Eng

iTrader: (1)

The new Darton LS2 dry sleeve solves the problems of previous dry sleeve installation failures. Bore will go from 4.125" to 4.160" max. Problem is the lack of used LS2 blocks. You must obtain a new core which must be stress relieved for best results. A lot of folks don't want to spend the grand or so for a new block. You do end up with a much better deal with the bigger bore because the larger bore helps unshroud the valves. Much lighter than the iron block as well.

Steve

ovaltobowtie2

Why is a 427 more expensive? Bigger bore for more machining??? I thought the rotating assemblies were the same cost. Help me here. Sleeving??

I was going to use an LQ4 block.

Patrick G

iTrader: (14)

The max you can bore an LQ4 block is .060" over, giving a 414 displacement.

kossuth

iTrader: (12)

The 6.0 blocks generally don't have enough meat in them to allow you to bore them over enough to get to 427. They have to be sonically scanned and the cast shift inside most blocks is enough to limit them to 408. As for the resleeved aluminum blocks, they are sometimes problematic and expensive to build. You get one built right they are great, but if you have a problem with the sleeves alot of times you have to start over with a new block.

Demon SS

iTrader: (3)

the cost of the sleeving process is what pushes the cost up on the aluminum block.
you can do a 421ci iron block with a standard ironblock bored 4.030(.030 over) and use a 4.125" crank

4.030x4.030x.7854x4.125x8=421ci

Beast96Z

iTrader: (21)

LS-1/6 aluminum blocks can only be bored .010" max. In order to get the large bore, you need to have the old sleeves removed and new larger sleeves installed. This is what they mean by sleeving. This process is fairly expensive. New sleeved blocks run anywhere from 2k to 4k depending on who does the work and what type of sleeve and machine work you get done. Steve@ race enginering, who posted above, is the co-inventor of the best sleeves avalible and really the only one I would trust to install my sleeves. Once you get the block, then the big cubes start to come out....

JakeFusion

iTrader: (7)

And I wouldn't recommend a 4.125" stroke, because of oiling problems and oversquare blocks don't like revving. A lot of people go iron block with a 4" stroke. The Eagle strokes are $1k cheaper than the Lunati or Callies, so the cheap blocks are coming in below $4k and they work well.

If you go with a Darton MID and go with an offset ground stock crank (3.71" or so and it's plenty strong) you can do 397 or 403 for about the same price as an iron block with a Callies or Lunati stroke. The difference is that it's undersquare, so it'll rev much better, and the 4.125 or 4.155" bore will allow more airflow at high rpms. Not to mention it's lighter than the iron block and makes similar torque and horsepower numbers with less displacement and generally less radical cams.

Demon SS

iTrader: (3)

I agree, we prefer to stay as close to square as possible or be a little under square. the benefit of more cubes by being over square is sometimes not worth the potential issues.

Scoobie

iTrader: (8)

Would an LS2 402 be cheaper then an LS1 397 or 403?

Beast96Z

iTrader: (21)

Considering you used the same exact parts in each motor, the LS2 would cost more because the block is more expensive and it has to be seasoned. As far as I can see, the diffrences are in the block price only.

ovaltobowtie2

So now your saying to that you dont recommend going over sqaure. Well everyone that has a 427 is oversqaure and they are getting it done. Im confused. So if I were to go with an LQ4 block 4.030 bore with a 4 inch stroke.......what CID would that be?? 408?
Thanks

This is going in a z06 and I have had people tell me not to do an iron block. I cant imagine 75lbs. making a huge difference. I meen these guys that add chargers are putting 50-60lbs on there front end as well. So I figure I might as well do it with cubes.

Your thoughts.

Demon SS

iTrader: (3)

i was just pointing out that you could do a 421ci they way I described it. In an out of square setup I prefer to have a little more bore than stroke. Actually most(if not all) 427's are a 4.125" bore and a 4" stroke or under square. The added weight of the iron block causes some weight transfer issues, but the extra weight of the iron block can be over come with suspension upgrades and weight reduction in other parts of the car.
a 4.030 bore and a 4" stroke would be a 408ci
a 4.060 bore and a 4" stroke would be a 414ci, some of the iron blocks can be bored to a 4.060 bore, just need to sonic check the block to be sure.

XpEdItIoUs

iTrader: (44)

Are ls2 402 reliable, dont you just need to get a 4.00 stroke crank and it will make it a 402 im thinking of building a shortblock and the 402 sounded like a good choice.