Forged Bottom End Power
Thread Starter
Intermediate
Joined: May 2018
Posts: 40
Likes: 0
From: Dallas, Texas
Forged Bottom End Power
I been wanting to start building my engine and I am looking to achieve about 1K HP with a turbo. I would obviously get a forged rotating assembly, but would I have to worry about the cylinder walls at all. Do I need to resleeve my LS6? If I don't when (at what power) should I start worrying about damages to the block, of course assuming the internals hold up. Also at that power what is usually what gives out first and what is where I should put the most research/money into?
Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
I been wanting to start building my engine and I am looking to achieve about 1K HP with a turbo. I would obviously get a forged rotating assembly, but would I have to worry about the cylinder walls at all. Do I need to resleeve my LS6? If I don't when (at what power) should I start worrying about damages to the block, of course assuming the internals hold up. Also at that power what is usually what gives out first and what is where I should put the most research/money into?
Factory crank is pretty strong but over 900 the forged crank makes sense. Turbos are easier on the rotating assembly and crank as you normally run lower revs and no belt load on the snout of the crank.
Racer
Joined: Aug 2017
Posts: 261
Likes: 75
From: Dfw Texas
My forged rod and piston LS1 that was in my car up to about a year ago made 916 to the wheel through an automatic. The cylinder walls are pretty thin so your tune needs to be spot on when you get to that level
Thread Starter
Intermediate
Joined: May 2018
Posts: 40
Likes: 0
From: Dallas, Texas
i've been running 800 at the tire with an ls6 for a few years but I think you will be pushing it at 1k with an ls6. The sleeves are pretty thin and prone to cracking at that level of cyl pressure. At that level it's pretty easy to push water and a thicker deck cyl head and studs help out.
Factory crank is pretty strong but over 900 the forged crank makes sense. Turbos are easier on the rotating assembly and crank as you normally run lower revs and no belt load on the snout of the crank.
Factory crank is pretty strong but over 900 the forged crank makes sense. Turbos are easier on the rotating assembly and crank as you normally run lower revs and no belt load on the snout of the crank.
So what do you recommend should I do Darton sleeves to a bigger bore or would this be cost-ineffective. If I do this I would probably put in a stroker crank as well to take advantage of the extra bore and make more power. Would this be relatively "safe" frot eh cylinder walls considering the sleeve, and is it cost-effective or am I just dumping money?
Thread Starter
Intermediate
Joined: May 2018
Posts: 40
Likes: 0
From: Dallas, Texas
yea I was thinking about Darton sleeves or something like that to get a bigger bore and if I do this I would probably go with a stroker crank to take advantage fo the extra cubes and make a little more power. Would this be relatively "safe" and cost-effective or would I just be dumping money into it?
Melting Slicks
Joined: Mar 2006
Posts: 2,754
Likes: 380
From: South Florida FL
yea I was thinking about Darton sleeves or something like that to get a bigger bore and if I do this I would probably go with a stroker crank to take advantage fo the extra cubes and make a little more power. Would this be relatively "safe" and cost-effective or would I just be dumping money into it?
If 1000whp was my goal, i'll just do an LS2/3 block, piston/rods and call it a day, for 1150+ i''ll do a crank while im there. I dont care for strokers, but if i do one, it'll do the appropriate sleeves. otherwise the piston hangs out the button of the oem sleeve, making it less reliable. from experience, the C5 chassis is ideal in the 850-950whp range anyway. after that, you should be snapping up the drivetrain, fighting traction and headgaskets. so plan ahead and stay in your lane if you want to enjoy the car
Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
it's all preference and peace of mind really, that has value to some people. it's easy to fall into the abyss of "what if" parts and end up over budget.
If 1000whp was my goal, i'll just do an LS2/3 block, piston/rods and call it a day, for 1150+ i''ll do a crank while im there. I dont care for strokers, but if i do one, it'll do the appropriate sleeves. otherwise the piston hangs out the button of the oem sleeve, making it less reliable. from experience, the C5 chassis is ideal in the 850-950whp range anyway. after that, you should be snapping up the drivetrain, fighting traction and headgaskets. so plan ahead and stay in your lane if you want to enjoy the car
If 1000whp was my goal, i'll just do an LS2/3 block, piston/rods and call it a day, for 1150+ i''ll do a crank while im there. I dont care for strokers, but if i do one, it'll do the appropriate sleeves. otherwise the piston hangs out the button of the oem sleeve, making it less reliable. from experience, the C5 chassis is ideal in the 850-950whp range anyway. after that, you should be snapping up the drivetrain, fighting traction and headgaskets. so plan ahead and stay in your lane if you want to enjoy the car
sleeved blocks and lsx stuff is much $ I'm a junkyard warrior Here's where I went Iron block 4.8 bored .020 gen4 rods with sps bolts, stock crank. AFR heads, dr phil cam.
you can go 900 + with this combo for less than you'll have in your short block. complete engine + a pair of garrett t66 turbos that will punch out 1200 if you want it.
the big bore and stroke isn't needed with an efficient turbo setup. good tune, fuel system, exh, tranny, ect... at 900 at the wheel you are going to break stuff. I went beefed auto tranny from rodney to cushion the hit and taller gears.
thinking of going taller still to 3.15s to load the turbos more. Upgrading to 3" down pipe and bigger turbo housings to carry the rpms with the short stroke motor a bit more to keep it in the power band longer
the little 4.8 iron block weighs a little more, but it's cheap, strong, and DONE. (done seems to be hard lately)
I don't think building tons of low end torq is needed with a big displacement You will end up bleeding off boost to hook it and better ramping up more progressively as the turbos hit pretty hard and you don't want to choke off on top end pull
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