Boring Out A Motor
#32
#33
Ok, well, that was an interesting read. Let me see if I can help.
Cummins motors can be bored in .020 and .040, or more technically .5mm and 1.0 mm. After that they are bored for a salvage sleeve and sleeved to standard size. Those are the factory available options. Sure there may be an aftermarket .030 or whatever, but I don't know. We always start our builds with factory pistons.
Next, the gasser stuff goes out the window. Yes, I will agree that there is no replacement for displacement, however EVERYONE here is missing the point. The chamber is in the piston people! When you over bore a cylinder, the piston for said cylinder is over sized to fit the hole, however your bowl, or chamber, is the same size! You aren't changing a thing! Thats the point, is that you can bore the motor and bring it back to factory condition. Compression, volume of bowl, everything is the same. The over sized piston is simply to allow the rings to seal against the cylinder wall.
If you want an extra 100hp, you need to either learn to tune your truck or take it to someone that knows how to. Tuning is the name of the game, and a lot can be done with just tuning.
Cummins motors can be bored in .020 and .040, or more technically .5mm and 1.0 mm. After that they are bored for a salvage sleeve and sleeved to standard size. Those are the factory available options. Sure there may be an aftermarket .030 or whatever, but I don't know. We always start our builds with factory pistons.
Next, the gasser stuff goes out the window. Yes, I will agree that there is no replacement for displacement, however EVERYONE here is missing the point. The chamber is in the piston people! When you over bore a cylinder, the piston for said cylinder is over sized to fit the hole, however your bowl, or chamber, is the same size! You aren't changing a thing! Thats the point, is that you can bore the motor and bring it back to factory condition. Compression, volume of bowl, everything is the same. The over sized piston is simply to allow the rings to seal against the cylinder wall.
If you want an extra 100hp, you need to either learn to tune your truck or take it to someone that knows how to. Tuning is the name of the game, and a lot can be done with just tuning.
#34
Mine is the pickup bored .030 over and yes it does run like a bad outta hell. but i do have some upgrades done to it. like an ip off a 8.3 cummins with afc changes and ground fuel plate and all the other good stuff. but with stock turbo and slightly larger injectors it runs a hell of alot better. but those mods are not sufficient reasons for the amount of power that pickup has. i believe that boring it out does help it quite a bit and it will lay down some good rubber and speed. i guess that deere mechanics build motors the best so if you can't run with the best in the field then get out.
#37
CNC laser guided, it already line bores to the center of the journal on the crank.
CNC=computer numerical control
you must enter in all factors.
i can go on all day what is involved about line boring, honing. just to much information to remember.
increasing the bore will probably only give 5 to 10 hp gains, if you want more hp you would have to enlarge to something of cummins 555, nt/nh 250.
on a diesel engine it would not make much of a difference on smaller bored engines.
if you want more HP, put a K19 in your truck, stock horsepower is 600 hp, That would be AWSOME (LONG BLOCKS START AROUND 30,000.00 )
CNC=computer numerical control
you must enter in all factors.
i can go on all day what is involved about line boring, honing. just to much information to remember.
increasing the bore will probably only give 5 to 10 hp gains, if you want more hp you would have to enlarge to something of cummins 555, nt/nh 250.
on a diesel engine it would not make much of a difference on smaller bored engines.
if you want more HP, put a K19 in your truck, stock horsepower is 600 hp, That would be AWSOME (LONG BLOCKS START AROUND 30,000.00 )
#39
Soooo...Does anybody know if the 6.7 crank will fit in a first gen block? Would the crank bearings be in the same spots? Would the rod journals line up? Would it have enough room to even rotate? Would there be room for the con rods to clear the bottom of the cylinder bore? If it could be done it would be an awesome mod for a VE cummins. Probably add 100 ft lbs before boost. If the crank could be made to fit somewhat easily, with just custom pistons and rods,maybe bearing caps and seals, it would be worth it if you were building an all out VE. I know that boring is a waste of time, but adding stroke would change the power curve a lot, right where the VE likes it. I'm the if it ain't broke,don't fix it type, I just want to know if it could be done or not.
#40