[24vcumminhard]

will benefit anything from using the 4000 rpm option on my smarty?

i have a bd single, smarty s06, bhaf and straight pipe.

 

[TXAustin]

You won't benefit as you will only break everything in the engine. Springs and pushrods are at the very least a must! The CRs are very tight in clearance between the cylinder and the rings which can spell out disaster. To prepare for this many guys (including me) will have their cylinders a little larger than stock so the rings have a better chance of not exploding with that much friction and movement. With only a turbo upgrade you are asking for big problems. However, Cummins specs tell us that the engine is rated for 4000rpms for 15 seconds - so you can decide for yourself on this one if you want to risk it or not.

 

[24vcumminhard]

You won't benefit as you will only break everything in the engine. Springs and pushrods are at the very least a must! The CRs are very tight in clearance between the cylinder and the rings which can spell out disaster. To prepare for this many guys (including me) will have their cylinders a little larger than stock so the rings have a better chance of not exploding with that much friction and movement. With only a turbo upgrade you are asking for big problems. However, Cummins specs tell us that the engine is rated for 4000rpms for 15 seconds - so you can decide for yourself on this one if you want to risk it or not.

thanks for the heads up, i'd rather not destroy my truck.

 

[cummins04.5handshaker]

There are many guys on here running the 4K rpm tune with only head studs, valve springs, bigger turbo and the fueling. Pushrods aren't really a big concern but if your in there then you mite as well toss them in... I'm building my motor for 4K rpms without boring the cylinders or putting a thicker gasket on. It's only gonna see 3500 when I pull it. The extra 500 is if anything breaks and the motor wraps up before I can let off the throttle.

 

[1baddiesel]

I wouldnt run it to 4k without some studs and springs atleast. My truck wont run that that far up even though ive got the tnt-r. But im sure thats probaly caused by me not having enough fuel to burn to get that high rpm at wot.

 

[SFmonster]

Look at some dyno charts.. is it really viable to run those rpm's unless you have a heavily built truck for racing?? not likely.. mine is built alot..and I dont run it.. so I doubt you and most others who run it actually need it..