Ls1 block score!

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Jarhead79

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Ls1 5.7 block score!

Now I know I've been all over the map with threads on motors and ideas, until tonight I couldn't make up my mind for sure, well almost sure! I scored this block that was fresh out of a machine shop, but not sure if it's just a stock ls1 bore, or if it has been bored, cylinders look awesome but slightly used so I'm guessing stock specs, but won't know until I get it checked, I wanted to do a 383, but this might be just as easy to pull off budget wise. Or I can sell the block or trade it for a good 350 block or one that has already been bored. Did I get a good deal you think for $100 bucks?
 

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Green79Scottsdale

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The biggest thing I do not like about the aluminum LS1 is the fact that you can not get much of an over bore on the stock cylinder liners. Seems like .010 is the max, if that. If you need to go bigger than that, the block needs to be resleeved, which gets expensive! If the bores are still within runout specs, hit it with a hone and new rings and go baby!

Did you get only the block for $100? My buddy recently put together a nice 5.3 based LS. He got a short block 5.3 for $50 and had it bored for stock LS1 pistons. He now basically has an iron LS1 that will handle more boost and punishment than an aluminum block. The aluminum blocks only save about 60 lbs. over an iron block. Iron block LS motors are still several hundred pounds lighter than a traditional small block.
 

Jarhead79

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I just have the block and main caps and bolts, a buddy had it for a build and then decided he didn't want to do an Ls for his 60s caddy, block looks in excellent shape and cylinder walls are still really nice, I gave him a hundy to help him out with some fast cash, I don't want to build a huge beast, I'd be fine with all stock, or mild, the honing looks good with minor scratches on the cylinder walls so I'm thinking it's just standard bore and has been cleaned up for rebuild, looks as though the cam bearings have been replaced as well or look to be in excellent shape, I'm clueless on Ls motors but I think it's a perfect candidate for a fresh motor rebuild, whether to use or to make a short block to sell to find a 383 project I've been wanting to do
 

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The stock bore of a LS1 is 3.898" (most just call it 3.90" for short). The max overbore is 3.905", though some do 3.902" to be safe.

A good hone job will "bore it out" but I would leave that to the machine shop. If it is still within STD limits, you can use that to build a 383 in the LS block. Look at the Lunati crank and rods, for abt $1200 plus pistons, not a budget build though. If they did a good job and the machining is done, then yeah, good start

My plans are to stick with the 5.3L block and I am thinking about doing a bore to the 3.898" size and use STD LS1 pistons, though I hear the con=rods and pistons do have weak points in them and one should at least go to after market for those anyway

NOTE: you will need new main bolts, should NOT re-use the OEM ones because they stretch.

also check local junkyards for a 5.3L. I got a complete engine, ECU, accessories for $600. Starting with a bare block might seem cheap at first, but buying the "rest" of the engine part by part can easily exceed the cost of just another engine. You can develop an inventory of stock parts from which you can assembly a common package (ie the 5.3L)

dougbert
 
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Jarhead79

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I wasn't planning on using them but they were with it
 

dougbert

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I wasn't planning on using them but they were with it

ah okay

I have a set of LS1 pistons and rods I got off of ebay for $230. I cleaned them up with looking at making a 5.7L out of a 5.3L block on a 3rd project. Then I read up on the weakness of the stock LS1 rods/pistons, so I don't know if I want to OEM on that or not.

If you are going to do LS work, I suggest spending $20 on a good LS rebuild book, several out there, to learn on them. I built a SBC for my FJ60 and spent way too much on buying parts for the "free block" I got. I learned a lot about SBC, but the most important item was that I should have done the junkyard 5.3L instead and would have saved thousands, since I bought many new SBC parts.

a refresh on my 2nd project with the 5.3L has cost me $2000 (including the engine for $600) for the engine side of things. Mostly on new gaskets, lifters, head work, pushrods, ARP bolts and the like. See sig below
 
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Jarhead79

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I've found a 5.3 with comp and wiring harness for $500. Just spitballing here but thought maybe I could get this into a short block at least and resale for a little profit if I couldn't use it for what I want
 
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dougbert

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I've found a 5.3 with comp and wiring harness for 600. Just spitballing here but thought maybe I could get this into a short block at least and resale for a little profit if I couldn't use it for what I want

good find and good ideas. I have found that most parts, if I shop smart, can be resold for the same and sometimes more than what I bought them for
 

Jarhead79

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345-400 hp range is what I'm ultimately after, just can't decide which way to go, Ls is so popular, but I'm more old school at heart, just can't make up my mind except to maybe build both! Lmao this is actually frustrating to make up my mind! Is that wrong!? Lol
 

Green79Scottsdale

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That power goal is certainly achievable with your current small block. Here is what you should do, IMO...

Price out a plan going both routes. Price out all the parts you will need for your current engine. Heads, intake, cam, headers, etc. Get a true accurate $$ amount.

Then do it for an LS. The biggest differences I see with going LS is the supporting pieces you need when you go EFI. A lot of people don't think of the fuel system you need to reliably do EFI. You will also need an ecm to control everything. You could go carb'd LS also. But you still have the ignition to control.

Anyway, after all the $$ are tallied up, ask yourself which way do you really want to go. Maybe an LS isn't all that more than hopping up your current small block. Maybe it's a lot more. Is it worth it? Those are questions only you can answer...
 

Jarhead79

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Appreciate the advice, looking at getting a book to aid me in the Ls area, I'm confident enough in the older motor areas to do it but I'm also relying on a friend to help who builds small blocks for a living, he's giving me pointers on it. I'm not looking to make a fortune but if I could break even on the Ls build and then use that money to go the old school route, I can get double the experience. Wish I could do both at the same time, but I'm limited in funds either way I go. On the Ls I've been researching parts in the area and think I can get most everything at a decent price to get the short block part rather quickly, would like to do carburetor although most say to do injection, there again carb is more appealing for some reason but also makes brings up fuel issues but I don't think it is as bad as computers and tuning and all that jazz. I still think the 383 is the way to go with my truck right now, money wise and time wise, I'm guessing the thought of rebuilding the Ls is more of a ***** and giggles project to say I did it. People around here want top dollar for junk dirty nasty looking motors, anywhere from $500 on up to a couple grand, I'm trying to budget $2000 in either build, just in the short or long block area, I know I can't really do an Ls for that little unless I get a donor bad block motor with all covers, sensors and such. I'm very calculativein decision making but I have issues in where to start for sure. Right now I'm just anxious to start somewhere, planning is making me a ancy! Lol
 
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