I have tried using the search function, unable to tell what year my bare block is. getting ready to machine it and I'm reading that there is a difference between the years on what size bore I can use.
I also tried looking up the numbers on the block but had no luck finding any information. are there any physical details or maybe a set of numbers I am missing to show me on what I can do with this block?
it does not have any displacement numbers in the usual spot I've know to look for,

I plan on starting with just the short block currently then will work on finding a set of heads for my goals. (if I have to switch the heads when I add boost I will)
this build is not in any rush, and i am not willing to swap the block as i already have the LS1 block laying around

Goals
chassis is a 350z 6mt which is mostly for Autox, doesn't need to be "streetable'

• 4in stroke
• Above average NA power~500whp,
• would like to supercharge down the road for no more than 650~whp
• camshaft can also be switched for boost

Im open to any and all ideas to change the build of my short block.

 

2y2147861 is on the back drivers of the block, but have no results searching this

 

it will be tough to make 500 whp with the 5.7 Na.

Is the block aluminum or iron ?

Post some pictures and im sure someone can help.

 

its an LS1 or an LS6 so an aluminum block.
As long as is somewhat around 500 im not going to cry over 25hp

 

It’s looking alot more like an aluminum 5.3L, possibly a L33. The LS1 blocks had that column cast into the valley, which you don’t have, so it’s almost definitely not an LS1 block. That would make it an LS6 block, but the LS6 blocks had bay windows below the cylinders, but your block does not. Instead it has the large hole drilled through from front to back. The only blocks I’ve seen like that are the Gen 3 5.3L blocks.

 

FWIW - my background, owned 4 LS cars, still have 3 of them, 2 strokers, heads cam, bolt on etc. Not an engine builder.

Edit - wrote by book, while pics were posted lol

Aluminum block LS1/LS6 bore & stroke

97-98 LS1 blocks a hone for clean up ~.005

99+ LS1/LS6 Improved liner positioning in 1999-and later 5.7L LS1 blocks and all LS6 blocks permit boring up to 0.010-inch oversize.

3.903 to 3.905 being typical

Long ago sleeving an LS1/LS6 block was an option for bigger bores up to an absolute max of 4.200 with 4.185 allowing a rebuild. Newer LS2/LS3/5.3 blocks are used now and sleeving LS1/LS6 is 🚫

Stroke - some that don't know how to correctly select pistons or do math will say ~3.9 is max stroke for an LS1/LS6 without oil consumption issues and pistons skirt wobble due to the length of the cylinder sleeve. However, 4 inch stroke works very well no issues with a competent engine builder who selects the correct taper pistons like Wiseco, JE, Summit etc all offer. Expect ~50,000 to 60,000 miles before a rering/refresh is needed with 4 inch stroke. Might go longer with good maintenance & oil changes might not. If you want a 300,000 miles or 8,000 rpms out of your LS - keep the stock stroke.

So a ~ LS1/LS6/punched 5.3 with 3.903 bore & 4 inch stroke makes for 383 cubic inches.

Regarding stroker cranks...pick your engine builder and discuss with the builder before buying. Some shops will want you to use their house favorite and not want to use anything else. Quality make the the same but if the build has preferences for XYZ - do yourself a favorite and use what the builder likes.

Center Counterweighted LS Crankshafts are the better choice for LS stroker cranks and only cost a few hundred dollars more. This style makes for a more ridged crank that isn't as hard on #2 & #4 bearings based on what a reputable engine builder shared.

Callies Compstar Center Counterweighted LS Crankshaft is one example. I think Callies was first to offer at at reasonable cost to the masses.

Borowski Race Engines, says we like to use fully counterweighted crankshafts in our engine builds. We believe the additional cost of 8 versus 6 counterweights is more than offset by the value delivered in engine longevity and performance. This design increases the stiffness of the crankshaft and reduces harmonics. The direct result is reduced flexing of the crank. The indirect results are greatly improved bearing life and a much stronger bottom end, particularly with a GM LS block.

Both of my LS strokers 383 & 416 have the older standard 6 counterweighted Callies CompStar cranks and no issues but the newer CCW is the smarter choice now that's its available.

Regarding Forced Induction, running a belt driven supercharger is very hard on the crank snout and #1 bearing. CompStar's are usually good to ~800whp with belt driven forced inductionfrom what I read, over that level sometimes the snout of the crank can snap or crack. If big Procharger power might be in the future a Magnum or DragonSlayer level of quality should probably be used. Same idea applies to all the various levels of cranks available from various manufacturers. (Just using Callies CompStar as example as I have those in my cars and am more familiar with them)

Improved Racing just released a 4 inch crank scrapper & windage trays! No more washer spacing etc. I'd definitely suggest checking out the IR parts.

Harmonics are a big deal so I'd suggest a Fluiddamper or ATI Superdampener. I have a 10% UD ATI on my 416.

 

On the driver side, where the head meets the block it. it should have a casting #

 

 

So it is a 5.7, 01-04

 

should I assume LS6 block?

 

Casting number says later LS1. LS6 only used one block# which was 12561168.

 

Definitely not an LS6 block. Looks like a 2000 LS1 block based on what's below from another thread.

Engine #'s

1998.......12550592,12559846,12559090

1999.......12550592,12559846


2000.......12559378,12559846, 12560626


2001.......12559378,12561168(Corvette/some lucky Camaro/Firebirds)


2002.......same as 2001 (service part# 12561166 2001-2004 LS1/LS6)

Edited - list above isn't complete, example

1999 - LS1 pulled from my 99 T/A

 

excuse my ignorance, but why does the valley on this block not match the typical LS1? For example the part you have to grind when doing an ls6 valley cover conversion?

 

I don't know.

Please see revised post. Found what I think is more accurate break down of part numbers.

 

Im pretty sure if the OP, or anyone else wanted to go with MID Darton sleeves, Steve@RED would gladly install them in an LS1/LS6 block......

 

Where's the picture that shows if it's stamped 5.3 or 5.7?

 

Thank you!
That's good to know!

I was about to list a virgin 20 year old, NOS LS6 block in marketplace for $250 but will keep for a while longer now. May take a few more years but will make a 427 out of that LS6 block yet!

 

You list an LS6 block for $250, and you'll need unlimited data on your phone, and probably need a new phone within 4 months!!!!!