Stroking a 4.8
01-20-2017, 07:20 AM
#21
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01-20-2017, 07:54 AM
#23
Okay well then can you help me with this KCS.....would a LS2 - 7 block be interchangeable with my LR4 given the possible longer crankshaft of the LR4?
This is the start of my research, why not find out from fellas like me first before I start asking machine shops questions? I haven't found much doing google on 4.8 strokers that really has specifics. So I thought this would be the place to start, and I have gotten some good info. So thanks guys.
This is the start of my research, why not find out from fellas like me first before I start asking machine shops questions? I haven't found much doing google on 4.8 strokers that really has specifics. So I thought this would be the place to start, and I have gotten some good info. So thanks guys.
Trust me when I say that the last thing a machine shop wants to hear from a customer is "well I heard from a guy on the internet..."
01-20-2017, 10:30 AM
#25
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Thank you KCS, my point exatly! And thank you for letting me know that the extra length comes from the external flandge that bolts to the flywheel.
JoeNova, I want what every gearhead wants....the most cubes in the small package you got. That way people think you just got a 5.3, but when you drag their *** and they go, " What you got in that thing??!!" You can dog'em with bragging rights.
OldLady, the more you open the bore size the more it unshrouds the intake. The longer rod the more torque the engine will build because the longer rod creates leverage. Long stroke short rod creates and uneven motion on the upstroke that makes the piston want to dig into the cylinder wall and create a scoring, often mistaken for having the wrong piston to wall clearance. A man named Judson Massingil once told me, "There is no substitute for cubic inches..." Torque is directly cubic inch related and proven in mathematical theory. Strokers need the right combination and better to learn it here than on the track with your your own money.
JoeNova, I want what every gearhead wants....the most cubes in the small package you got. That way people think you just got a 5.3, but when you drag their *** and they go, " What you got in that thing??!!" You can dog'em with bragging rights.
OldLady, the more you open the bore size the more it unshrouds the intake. The longer rod the more torque the engine will build because the longer rod creates leverage. Long stroke short rod creates and uneven motion on the upstroke that makes the piston want to dig into the cylinder wall and create a scoring, often mistaken for having the wrong piston to wall clearance. A man named Judson Massingil once told me, "There is no substitute for cubic inches..." Torque is directly cubic inch related and proven in mathematical theory. Strokers need the right combination and better to learn it here than on the track with your your own money.
01-20-2017, 10:38 AM
#26
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OldLady, the more you open the bore size the more it unshrouds the intake. The longer rod the more torque the engine will build because the longer rod creates leverage. Long stroke short rod creates and uneven motion on the upstroke that makes the piston want to dig into the cylinder wall and create a scoring, often mistaken for having the wrong piston to wall clearance. A man named Judson Massingil once told me, "There is no substitute for cubic inches..." Torque is directly cubic inch related and proven in mathematical theory. Strokers need the right combination and better to learn it here than on the track with your your own money.
01-20-2017, 11:40 AM
#27
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OldLady, thats what I am trying to find out. Another fella on this thread said yes it would work. Also KSC posted a link to an artical I havent read yet. From what I hear in this forum and from reading, alot of emphasis is placed on sonic testing before going the massive 120 over. Back in the day when you went big you also filled the block and only ran your pass down the strip and shut it off. So my personal judgement would be to go half that at 60 over and see if the market has common sizes in that range. Check the common piston sizes and make a selection. The bigger the better. If you want to save some meat then save. But youll be happier with more now that less later I garuntee!
01-20-2017, 11:43 AM
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OldLady, thats what I am trying to find out. Another fella on this thread said yes it would work. Also KSC posted a link to an artical I havent read yet. From what I hear in this forum and from reading, alot of emphasis is placed on sonic testing before going the massive 120 over. Back in the day when you went big you also filled the block and only ran your pass down the strip and shut it off. So my personal judgement would be to go half that at 60 over and see if the market has common sizes in that range. Check the common piston sizes and make a selection. The bigger the better. If you want to save some meat then save. But youll be happier with more now that less later I garuntee!
01-20-2017, 01:50 PM
#29
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If you stroke a 5.3 with a 4" crank, you have ~359 ci. A 6.0 is 364 ci.
Not only that, but a 6.0 complete shortblock will go right in your truck with zero changes. 4.8/5.3 heads drop right on and give increased compression. You are literally money ahead just swapping in a 6.0 shortblock.
Stroking a 5.3/4.8 is just plain silly when it comes to cost effectiveness. You could buy a 6.0 shortblock for the same price as machining and assembly for the 4.8/5.3 block, not counting the rotating assembly.
10-01-2022, 06:44 AM
#33
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What?! crank is the same.. the only difference in displacement comes from a shorter rod length a simply longer rod would bump up the cubes to 5.3 from 4.8 but like i said in my other post it would be best to bore it to the ls1 spec and then go from there as the market for that is way more established and plenty of parts around but i believe its a 4" crank that goes in 
10-01-2022, 10:03 AM
#35
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10-03-2022, 09:53 AM
#37
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