89LS1RS

iTrader: (1)

does anyone know if an ls1 crank fits in an ls4 block? can you use an ls4 block for a rwd build? the bore is 3.78

deadhorse66

iTrader: (2)

Yes, and yes. The block is the same as the truck block, just fitted for the W platform. The oil pan, intake manifold and a lot of other stuff has to go though. The crankshaft reluctor is different on your Gen III crank is the only difference.

Project GatTagO

iTrader: (7)

LS4 is aluminum block. You may want to also look into the 5.3L that came in the Trailblazers. They used an aluminum block as well.

Andrew

odarabla

iTrader: (1)

I thought they where aluminum!! I wonder why they didn't just make the truck block aluminum?

un17real

just because of the higher the weight the higher the load of the truck stresses out the engine thus working hader yada yada......

89LS1RS

iTrader: (1)

because brand new ls4 blocks are available for 400, seems like a cheap start to a build. i have an ls1 now, is everything i have on my motor going to switch over to the new block? covers, oilpan, heads, intake, accesory drive. can you use a regular waterpump on the block? i would get a new rotating assembly in it, but can i have it set up with the same reluctor and everything, so there will be no changes other than swapping shortblocks?

scatillac

iTrader: (12)

The LS4 block has the GM "corporate" bolt pattern on the rear, not the Chevy Gen III&IV/SBC pattern. It will only fit the FWD GM trans bellhousings and some other configurations (unless you use an adapter plate) .

Greg Fergus has about 10 of these (new) at a damn good price. They're great for a Fiero stealth conversions !

jay_lt4

iTrader: (4)

yup, bell housing bolt pattern is different, also they have no provisions for mounting a starter,, on the ls4 cars the starter is bolted to the top of the transmission

89LS1RS

iTrader: (1)

cool, it only took a couple days for someone to finally tell me what i needed to know. basically, i cant use it for a rwd car. someone else told me otherwise. and i was almost gonna buy one of those blocks. for the starter, is there just no tapped holes, but a machine shop (or me) could drill and tap and be ok on that issue. and then getting a bellhousing/transmission setup wouldnt be too bad. maybe it is possible? but it looks like the cheap price of the block isnt gonna be so cheap after all the custom fitment needed. anyone else have any comments, has anyone actually used this block in a rwd car?

jonathan8751

iTrader: (7)

great info I have an 06 impala ss and wanted to see if I could put my ls2 out of my gto.