Used block
Thread Starter
Heel & Toe
Joined: Nov 2014
Posts: 23
Likes: 0
Used block
Think of buying used block to build a little stronger motor for my 1980 L 48, found one used with new flat top pistons but block has been bored , He said forty over. Is this not quite a bit? $250 apparently has crank in it. Is this good price up here in Canada. He changed his plans and went another route said it has about 25 miles on it. Any concerns about flat top pistons and head selection? Thanks for your reply. and time.
Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
.040 is no big deal. as for used blocks and guys who decide to "go another route" after putting all the time and money into a motor, I personally would assume the worst. meaning there is likely some problem with it, he forgot oil, cracked, shoddy work, who knows...I would pass.
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
.040 is no big deal. as for used blocks and guys who decide to "go another route" after putting all the time and money into a motor, I personally would assume the worst. meaning there is likely some problem with it, he forgot oil, cracked, shoddy work, who knows...I would pass.
25 miles and yank a perfectly good engine, doesn't happen. Go to a good speed shop and pay $250-300 from them for a block.They will make sure the block is OK and it is peanuts compared to the entire build and you have piece of mind knowing you can take it back if anything goes wrong. Insist on paying by credit card another way of dealing with a problem with the engine.
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
Think of buying used block to build a little stronger motor for my 1980 L 48, found one used with new flat top pistons but block has been bored , He said forty over. Is this not quite a bit? $250 apparently has crank in it. Is this good price up here in Canada. He changed his plans and went another route said it has about 25 miles on it. Any concerns about flat top pistons and head selection? Thanks for your reply. and time.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
x2 on ads that say "went another route". thats code word for its fubared and need to unload it. Otherwise if it was good why would they sell it?
Somethings wrong
Most machine shops got plenty of good inspected cores laying around their shop. Safer bet than most
Somethings wrong
Most machine shops got plenty of good inspected cores laying around their shop. Safer bet than most
Safety Car
Joined: Jan 2009
Posts: 3,736
Likes: 56
From: anchorage ak
I agree the if there us an issue at .040" over then you've got very little room to work with and like e every one else has said all you ha e to go off is the seller word which if whom you don't know, buyer beware. And I also think that if you stud your block or go even further and do a 4 bolt splayed mains with billet or nodular iron caps with the inner bolt studded you got the beginnings of a bullet proof bottom end, BK built a 383" out of his 2 bolt probably making 450 horse runs low twelves with probably 200+ 1/4 mile runs & it holds up. Like some one has mentioned you can buy a block ready to go from the machine shop, but if your block is in good shape you can build it to live at 600 horse.
Last edited by bluedawg; Aug 18, 2016 at 04:02 PM.
Thread Starter
Heel & Toe
Joined: Nov 2014
Posts: 23
Likes: 0
ITs a friend of a friend. supposed to be because of heads or rods were not right or something is why he went different route. He says block crank and pistons are good. Thanks again for your time, and opinions.
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Burning Brakes
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Race Director
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From: Athens GA
St. Jude Donor '12-'13, '15- '16-'17-'18-'19, '21
Racer
Joined: Apr 2013
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From: South carolina
People's minds due change I had a 400 block bored 10 over and ended up selling it a few months later when an almost free ls1 came out of my friends camaro when he totaled it. But due agree in a sense since alot of people will say anything to sell something so due I believe 25 miles and yanked no
Last edited by brick1234; Aug 19, 2016 at 06:59 PM.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
I get the changing mind thing believe me
What pistons are in there. how far in the hole?
Without that you dont know what head to get, compression ratio to shoot for etc. Perhaps he made that mistake of not checking who knows
Will he let you bring it by a machine shop to be checked out first before buying? that would instill a little confidence.
Know of a place for about a grand you can get a fresh shortblock. It wont be anything fancy but for a cheap motor-Buddy uses them, puts a nice ported Brodix head on, a 200 shot bit solid flat tappet and runs 10s wiht it. Blows the shortblock gets another one all the old stuff goes back on it. Forged piston up grade 100.
Not something I would do but he goes fast on budget.
What pistons are in there. how far in the hole?
Without that you dont know what head to get, compression ratio to shoot for etc. Perhaps he made that mistake of not checking who knows
Will he let you bring it by a machine shop to be checked out first before buying? that would instill a little confidence.
Know of a place for about a grand you can get a fresh shortblock. It wont be anything fancy but for a cheap motor-Buddy uses them, puts a nice ported Brodix head on, a 200 shot bit solid flat tappet and runs 10s wiht it. Blows the shortblock gets another one all the old stuff goes back on it. Forged piston up grade 100.
Not something I would do but he goes fast on budget.
Safety Car
Joined: Oct 2007
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From: Austin Texas
Corvette of the Year Winner 2017
2016 C3 of Year Finalist
pistons make all the difference, for me forged pistons are mandatory,
Hyper tech pistons = problems down the road literally.
flat top pistons are not performance pistons. rods stock ?
crank, cast or forged ? big difference if you plan to build performance.
.040 overbore, means you can safely rebore only 1 more time to .060.
I would disassemble and inspect everything, if all looks good reassemble.
If I were planning a performance build, I would pass on this.
Hyper tech pistons = problems down the road literally.
flat top pistons are not performance pistons. rods stock ?
crank, cast or forged ? big difference if you plan to build performance.
.040 overbore, means you can safely rebore only 1 more time to .060.
I would disassemble and inspect everything, if all looks good reassemble.
If I were planning a performance build, I would pass on this.
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
$250 for a shortblock that may or may not be sound is not worth getting worked up about. Buy the thing, find out what issues it may have, and from there decide if you want to fix the problems -if any. It may be just fine (good machining, good parts and assembly) and a very good deal. There are no issues with flat top pistons whether they are sand-cast, hypereutectic, forged 4032 or 2618. Your L-48 uses a sand-cast dished piston. Any head you would use on your L-48 will be better with the flat tops due to slightly higher compression. A .040 overbore isn't a problem. Really, this could be a great buy or a waste of $250, which isn't that much to put at risk.
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
The key is to inspect the parts and ask the right questions.
I've never sold anything that I didn't think was 100%. If I have a part or something that is questionable, it goes into the scrap pile. I know a lot of people are not as honest as I am, but I wouldn't dismiss all sellers.
-- Joe
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
I sold a set of AFR 195's a few years ago that had nothing but idle time on them, because I decided to go a different direction (210s with larger chambers).
I build a 355 for a 4x4, had it dropped in and cam broken in and then another (much nicer) truck fell into my lap. I decided to part the truck out and sold a motor that essentially had about 3 miles of drive time on it.
Inspect the parts, ask the right questions. But even worst case scenario, look at the sum of the parts. I'd pay $250 for a .040 over motor with good crank, rods, pistons. Even if something happened I could probably re-use 80% of the parts, so base the price on that. If it's $1,000 worth of parts it's a good deal. if it's $300 worth of parts walk away.
-- Joe
Thread Starter
Heel & Toe
Joined: Nov 2014
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Gonna try and see it this week. Apparently he bought a different car. Best friends buddy has it so not complete stranger. I went to school with him just did not know him that well. He said he paid $250 for pistons new and $500 in machine work.