Gen 5 crank in a Gen 4?
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Gen 5 crank in a Gen 4? I know the Gen 5s and Gen 4s are quite different but I got a call from my local machine shop and the crank is bad and the journals need some work. I found someone selling a 12674745 crank (which is apparently forged) near me for $150 hoping that it will work, If so that'd be great because I'd rather not drop $1000 on a forged crank
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From: Mefis
I know the Gen 5s and Gen 4s are quite different but I got a call from my local machine shop and the crank is bad and the journals need some work. I found someone selling a 12674745 crank (which is apparently forged) near me for $150 hoping that it will work, If so that'd be great because I'd rather not drop $1000 on a forged crank
Putting the L8T crank in a Gen4 build is getting pretty popular, so yes, a gen5 crank will work in a gen 4 iron block. The L8T crank has center counterweights which wont work in an aluminum block without a little work, but fits an iron block fine. I haven’t been in enough Gen5 engines to know weather or not if ALL the Gen5 cranks have the center counterweights. If you have an iron block, you should be fine.
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This guy has a complete build he documents building a 5.3 with an L8T crank. It's been a bit since I watched it, but the things I remember was center counter weights, reluctor ring if using a 24t needs clearanced, and the snout. As far as the snout I can't remember for sure but either the balancer or snout had to be machined slightly. You will have to watch the series to know for sure. The snout issue comes up in a later video when he is assembling the long block. The 24t reluctor issue may have been in a truck doug video where he built one of these. I think truck dougs youtube is 4l80guy or something like that he is a member here.
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My shop just finished balancing my L8T crank for a 6.0L iron block stroker turbo build, balance job wasn't expensive with K1 rods and Wiseco pistons, I'll ask them tomorrow how much heavy metal it took. They also cut the snout keyway longer toward the first journal so I can use a double row timing set. I will have to use a later model flexplate but that's no biggie.
They discuss the snout issue a bit here. It's not just the keyway, but also the diameter of the snout is smaller causing the timing gear and harmonic balancer to be loose.
https://www.yellowbullet.com/threads/turbo-l8t.2689840/
https://www.yellowbullet.com/threads/turbo-l8t.2689840/
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Putting the L8T crank in a Gen4 build is getting pretty popular, so yes, a gen5 crank will work in a gen 4 iron block. The L8T crank has center counterweights which wont work in an aluminum block without a little work, but fits an iron block fine. I haven’t been in enough Gen5 engines to know weather or not if ALL the Gen5 cranks have the center counterweights. If you have an iron block, you should be fine.
l8t check all 3 boxes good fast cheap cranks hqave run over 2k hp, they are full ccw forged 3.86 stroke
wiseco has 3.90 stroke pistons, i hope to ceramic coat and make up some of the 4 thou
alum blocks with 3.8 bored honed liner with 1/2 studs should do it
fuel hoops if you need more ls9 should support an ez 1200 hoops more than the block cn hold
I'm also thinking of installing liners for a much bigger 4.1 bore and stronger but the liners are pricey and the block need 3-4k of mchibe work
thinking since the liners recommed line bore, getting doweled billet main caps and studs
should hold 2k or so with good bottom end with boostline rods
l8t craks need a special timing gear and 8 bolt FW or auto flexplate both are ez to get
scrounged up 3 alum blocks so we will see how fare it goes
2 of em look very clean and GTG with only a hone
one block has a score in one liner than might clean up with 3.80 bore if not it get's the liners
l8t works fine with alum blocks the iron blocks need a bit of clearncing
l8t check all 3 boxes good fast cheap cranks hqave run over 2k hp, they are full ccw forged 3.86 stroke
wiseco has 3.90 stroke pistons, i hope to ceramic coat and make up some of the 4 thou
alum blocks with 3.8 bored honed liner with 1/2 studs should do it
fuel hoops if you need more ls9 should support an ez 1200 hoops more than the block cn hold
I'm also thinking of installing liners for a much bigger 4.1 bore and stronger but the liners are pricey and the block need 3-4k of mchibe work
thinking since the liners recommed line bore, getting doweled billet main caps and studs
should hold 2k or so with good bottom end with boostline rods
l8t craks need a special timing gear and 8 bolt FW or auto flexplate both are ez to get
scrounged up 3 alum blocks so we will see how fare it goes
2 of em look very clean and GTG with only a hone
one block has a score in one liner than might clean up with 3.80 bore if not it get's the liners
l8t check all 3 boxes good fast cheap cranks hqave run over 2k hp, they are full ccw forged 3.86 stroke
wiseco has 3.90 stroke pistons, i hope to ceramic coat and make up some of the 4 thou
alum blocks with 3.8 bored honed liner with 1/2 studs should do it
fuel hoops if you need more ls9 should support an ez 1200 hoops more than the block cn hold
I'm also thinking of installing liners for a much bigger 4.1 bore and stronger but the liners are pricey and the block need 3-4k of mchibe work
thinking since the liners recommed line bore, getting doweled billet main caps and studs
should hold 2k or so with good bottom end with boostline rods
l8t craks need a special timing gear and 8 bolt FW or auto flexplate both are ez to get
scrounged up 3 alum blocks so we will see how fare it goes
2 of em look very clean and GTG with only a hone
one block has a score in one liner than might clean up with 3.80 bore if not it get's the liners
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Joined: Oct 2002
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From: Mefis
l8t works fine with alum blocks the iron blocks need a bit of clearncing
l8t check all 3 boxes good fast cheap cranks hqave run over 2k hp, they are full ccw forged 3.86 stroke
wiseco has 3.90 stroke pistons, i hope to ceramic coat and make up some of the 4 thou
alum blocks with 3.8 bored honed liner with 1/2 studs should do it
fuel hoops if you need more ls9 should support an ez 1200 hoops more than the block cn hold
I'm also thinking of installing liners for a much bigger 4.1 bore and stronger but the liners are pricey and the block need 3-4k of mchibe work
thinking since the liners recommed line bore, getting doweled billet main caps and studs
should hold 2k or so with good bottom end with boostline rods
l8t craks need a special timing gear and 8 bolt FW or auto flexplate both are ez to get
scrounged up 3 alum blocks so we will see how fare it goes
2 of em look very clean and GTG with only a hone
one block has a score in one liner than might clean up with 3.80 bore if not it get's the liners
l8t check all 3 boxes good fast cheap cranks hqave run over 2k hp, they are full ccw forged 3.86 stroke
wiseco has 3.90 stroke pistons, i hope to ceramic coat and make up some of the 4 thou
alum blocks with 3.8 bored honed liner with 1/2 studs should do it
fuel hoops if you need more ls9 should support an ez 1200 hoops more than the block cn hold
I'm also thinking of installing liners for a much bigger 4.1 bore and stronger but the liners are pricey and the block need 3-4k of mchibe work
thinking since the liners recommed line bore, getting doweled billet main caps and studs
should hold 2k or so with good bottom end with boostline rods
l8t craks need a special timing gear and 8 bolt FW or auto flexplate both are ez to get
scrounged up 3 alum blocks so we will see how fare it goes
2 of em look very clean and GTG with only a hone
one block has a score in one liner than might clean up with 3.80 bore if not it get's the liners
You can also do a 6.2" Molnar rod with a shelf 1.115" piston.
Plan to spend some money on mallory for balancing.
I don’t see this as much of a cost savings when it’s all said and done. You limit your parts selection for pistons and still haven’t addressed the possible harmonic balancer issues due to the snout being a slightly smaller diameter than an LS crank snout.
The problem with all the 6.100" rods is like 99% of them are .945" pin which most off the shelf pistons for longer stroke will be made for .927", then the cranks are 8 bolt on the flywheels side and finally the snout side needs the SDPC front gear.
rkreigh wrote
l8t check all 3 boxes good fast cheap cranks hqave run over 2k hp, they are full ccw forged 3.86 stroke
wiseco has 3.90 stroke pistons, i hope to ceramic coat and make up some of the 4 thou
I think you mean 0.040" here?
rkreigh wrote
l8t check all 3 boxes good fast cheap cranks hqave run over 2k hp, they are full ccw forged 3.86 stroke
wiseco has 3.90 stroke pistons, i hope to ceramic coat and make up some of the 4 thou
I think you mean 0.040" here?
I'm running a complete stock L8T rotating assembly in a 6.2L block. You'll need a gen5 lower timing gear. I took the easy way and made up the .002" rattle room with green locktite. The keyway doesn't support it much so I would recommend doing it the right way if you plan on running a bunch of spring pressure.
essentially it's 400ci stroker for around $2000 all in (having built it twice due to no oil pressure first go around) If I break the stock pinner *** rods Texas speed makes a drop in kit, no balance needed.
ive grabbed a few other L8T cranks while they're cheap for future projects. 346 in an LC9 block with gen 5 heads ought to be a stock block contender.
or a 388 in an iron 6.0 block to fit gen 4 rec port heads would make killer power.
L8T stock bobweight is ~1700g so most combos won't need a whole lot of Mallory
essentially it's 400ci stroker for around $2000 all in (having built it twice due to no oil pressure first go around) If I break the stock pinner *** rods Texas speed makes a drop in kit, no balance needed.
ive grabbed a few other L8T cranks while they're cheap for future projects. 346 in an LC9 block with gen 5 heads ought to be a stock block contender.
or a 388 in an iron 6.0 block to fit gen 4 rec port heads would make killer power.
L8T stock bobweight is ~1700g so most combos won't need a whole lot of Mallory
I'm running a complete stock L8T rotating assembly in a 6.2L block. You'll need a gen5 lower timing gear. I took the easy way and made up the .002" rattle room with green locktite. The keyway doesn't support it much so I would recommend doing it the right way if you plan on running a bunch of spring pressure.
essentially it's 400ci stroker for around $2000 all in (having built it twice due to no oil pressure first go around) If I break the stock pinner *** rods Texas speed makes a drop in kit, no balance needed.
ive grabbed a few other L8T cranks while they're cheap for future projects. 346 in an LC9 block with gen 5 heads ought to be a stock block contender.
or a 388 in an iron 6.0 block to fit gen 4 rec port heads would make killer power.
L8T stock bobweight is ~1700g so most combos won't need a whole lot of Mallory
essentially it's 400ci stroker for around $2000 all in (having built it twice due to no oil pressure first go around) If I break the stock pinner *** rods Texas speed makes a drop in kit, no balance needed.
ive grabbed a few other L8T cranks while they're cheap for future projects. 346 in an LC9 block with gen 5 heads ought to be a stock block contender.
or a 388 in an iron 6.0 block to fit gen 4 rec port heads would make killer power.
L8T stock bobweight is ~1700g so most combos won't need a whole lot of Mallory
