Just got to talking the other day and someone asked if you could install bigger sleeves in a 5. 9 cummins and run larger pistons? How much bigger is possible?
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Competition Can you put bigger sleeves/pistons in the cummins? More cubes?
- Thread starter GOT-Torque
- Start Date
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As I understand it, the 5. 9 does not have sleeves, but you can bore it out... ... ... ... ... ...
Well over 400 cubes!!
J. R.
J. R.
How much bigger can you go on the bore before the cylinder walls start to get too thin, and are there certain year blocks that have thicker cylinder walls allowing a larger bore size than others.
So how big have people gone? And did they change the stroke/crank as well? Just curious...
If the cylinder walls get too thin, you can always put in dry sleeves to bring back the thickness you need. The real limiting factor in overboring a motor is the width between the cylinders. If you bore too far, the area where the gasket seals between the cylinders gets too thin and you can not hold a head gasket. I have no idea what is safe on the Cummins.
Adding stroke is always a good way to add cubes and torque at the expense of RPMs. If you increase the stroke, it is best to lighten the pistons and rods (without sacrificing strength) so the motor can safely rev higher. A common way to do this in a race motor is to offset grind the rod journals smaller and use rods from another motor that have the dimensions needed. Other options include a crank with longer stroke that can be fit into the block or welding up the crank and offset grinding the rod journals to maintain the factory diameter with a longer stroke.
Adding major cubes to a race motor gets expensive in a hurry!!!
Steve Keim
Adding stroke is always a good way to add cubes and torque at the expense of RPMs. If you increase the stroke, it is best to lighten the pistons and rods (without sacrificing strength) so the motor can safely rev higher. A common way to do this in a race motor is to offset grind the rod journals smaller and use rods from another motor that have the dimensions needed. Other options include a crank with longer stroke that can be fit into the block or welding up the crank and offset grinding the rod journals to maintain the factory diameter with a longer stroke.
Adding major cubes to a race motor gets expensive in a hurry!!!
Steve Keim
Stock bore is 4. 02" and stroke is 4. 72", I think the 8. 3L cummins bore is 4. 49" and stroke is 5. 31". Can you fit pistons (and crank for that matter) from a 8. 3 in a 5. 9 block? I imagine the 8. 3 block (and crank) is longer to leave more room between the cylinders and this is not possible. Otherwise it would seem like a popular swap!
From my memory, I think there was only about 1/2" to 3/4" of space between the cylinders on the 5. 9 cummins.
From my memory, I think there was only about 1/2" to 3/4" of space between the cylinders on the 5. 9 cummins.
PToombs said:No substitute for cubic inches!
Theres no replacement for Displacement :-laf
Michael
359 of course... ... ... 
Yeah the complete truck was for sale, but now it may just be the rolling chassis. I am planning on building a tube frame, carbon fiber body. It will be ran in the MOD class and continue to pull with OSTPA in the SMFWD class. The body and chassis will sell as it sits without the motor, clutch, weight bracket, reese insert pulling hitch I built forever ago, Razors Edge name, data logger, water injection. Unless someone wants the clutch, which is a 4 disc with a lakewood blowproof bellhousing. Then I will add $7000. 00 to the price since it will need to be replaced if it sells. I haven't really advertised the truck too much yet since I want to finish the last 2 DHRA pulls. I will end up in 4th in the points and will have only been at 5 out of the 9 events. Since people will ask, I have a price of $30,000. 00 on the rolling chassis. I think it is a fair price for what the drivetrain has, ladder bars, loops, the paint job, 8" stack, all the guages, stainless bump stops, 33x12. 50x 16 Trxus Radials on American Eagle or American racing (i forget which brand) wheels, single driveshafts with 1480 and 1410 yokes, a truck known in a large part of the country. I think that includes the 241 DHD transfer case coming with the truck also. Extra set of gears front and rear if I don't use them in the next few weeks. A single racing seat with a 5 point seat belt, hand throttle setup, and too many other thing to try to think of and list.
Straley
Yeah the complete truck was for sale, but now it may just be the rolling chassis. I am planning on building a tube frame, carbon fiber body. It will be ran in the MOD class and continue to pull with OSTPA in the SMFWD class. The body and chassis will sell as it sits without the motor, clutch, weight bracket, reese insert pulling hitch I built forever ago, Razors Edge name, data logger, water injection. Unless someone wants the clutch, which is a 4 disc with a lakewood blowproof bellhousing. Then I will add $7000. 00 to the price since it will need to be replaced if it sells. I haven't really advertised the truck too much yet since I want to finish the last 2 DHRA pulls. I will end up in 4th in the points and will have only been at 5 out of the 9 events. Since people will ask, I have a price of $30,000. 00 on the rolling chassis. I think it is a fair price for what the drivetrain has, ladder bars, loops, the paint job, 8" stack, all the guages, stainless bump stops, 33x12. 50x 16 Trxus Radials on American Eagle or American racing (i forget which brand) wheels, single driveshafts with 1480 and 1410 yokes, a truck known in a large part of the country. I think that includes the 241 DHD transfer case coming with the truck also. Extra set of gears front and rear if I don't use them in the next few weeks. A single racing seat with a 5 point seat belt, hand throttle setup, and too many other thing to try to think of and list. Straley
JFaulkner said:
Roger that, seen wayyy too many 540 ci Ferds siting there scratching their heads, wondering how that dang 6 cyl smoker :-laf just blew their doors off.
Now what you need is large displacement AND forced induction!
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