GMPP LS1 blocks
Discussion
robbyd said:
what better alternatives are there in aluminium at that price?
would you go for LS2 or an iron block?
cheers
All the base factory blocks are roughly same price anyway, and iron even cheaper.would you go for LS2 or an iron block?
cheers
As for what I'd use....depends what you actually need. Obviously LS1 would make an engine swap/replacement/rebuild easiest if you already had an LS1
But my first choice for any build with a factory alloy block would be LS9, then LSA, then LS3/2 or whatever.
LS9 does carry a hefty price tag though and probably not needed by most. I wouldnt consider iron for anything I'd ever want, just dont see the point in the weight penalty.
I've just had an LS2 block for mine for quite a few years albeit with slight mods.
Of all alloy blocks, LS1 would be the least desirable ( fitment ease aside of course )
Boosted LS1 said:
Die cast ls1 is actually one of the stronger blocks, lsa, ls9 excepted. It has decent material around the crankcase webs which became weaker once the slots were designed into later blocks.
OP, what's wrong with your ls1 block?
But some of the thinnest liners....that's the weak area.OP, what's wrong with your ls1 block?
robbyd said:
Engine is supercharged and has had one slight rebore already - figured when I freshen it up won't be able to do another so starting with standard bores again is best option...
LS1 will take a 5 thou hone...and that's from new. There isnt enough room for a safe rebore as such.10thou would be a gamble for sure....it may last a long time, but it may not.
You could have your block re-linered...bit hit or miss that one but is doable.
Or a new block of some sort....but LS2 block etc will then require further parts to make it fit where an LS1 once lived. An LS1 block, even better if same bore size as current then would literally be a simple replacement
Although exactly what is wrong with yours that it actually needs replaced ?
robbyd said:
stevieturbo said:
Although exactly what is wrong with yours that it actually needs replaced ?
Just the fact that it already had a minimal rebore, and if it gets honed during a rebuild that'll probably be too much for a blown engine no?robbyd said:
Just the fact that it already had a minimal rebore, and if it gets honed during a rebuild that'll probably be too much for a blown engine no?
But you still havent stated what is wrong with yours ?What has happened that you feel it either needs a rebore ? Did it blow up, or melt pistons or something ?
robbyd said:
Nothing wrong as such - done 50k running 8psi and has a bit of blow-by, so thinking sometime soon it could do with a freshen up. Will also be upping the boost when I eventually get my 175ax fitted... insurance really.
If there is nothing wrong with the bores, a light hone to give new rings a surface to bed into will be fine.No need at all to start considering a larger bore if there is nothing wrong with the existing bore.
robbyd said:
Boosted LS1 said:
OP, I'm sure your block won't have been bored. It may have been honed but until you look into it you'll not know by how much.
I'll need to dig it out but the spec sheet for the forged pistons did indicate a plus size...robbyd said:
I'll need to dig it out but the spec sheet for the forged pistons did indicate a plus size...
It is generally recognised that 5 thou over is as much as you can go with an LS1 block...and that would not be regarded as a rebore. ( although some might call it that )So pistons may be oversize...but it would be very unusual for them to be any larger than that. ie 3.903" instead of original 3.898"
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