Newbie question about the 5.9HO and Non HO motors

superbird03 · 09-03-2008, 10:09 PM

I am new to this site and kind of have a basic question but haven't been able to find the answer on here yet. What is the difference between the 5.9HO motors and non HO motors. Just a different program from dodge or? I have a 2003 cummins with an automatic that i recently bought and I am a little worried on what I can do to the motor to make more power without hurting the stock transmission. Any advice would be appreciated!

***rufushusky*** · 09-03-2008, 10:40 PM

Any easy way to find out which one you have is look at the valve cover and it will tell you how much advertised hp you got

235 = California
250 = SO
305 = HO

As far as trans you could have either a 48re or a 47re. The 48re took over for the 47re in late 2003. If a truck is driven too hard stock you can destroy a stock trans but you really got to beat on it. The 47re have the rep of being a weaker trans than the 48re. The 48re is stronger than most people give it credit for, I have had my truck modded for 30k of the 33k miles I have owned it. The 147k mile old trans can handle the level one of Smarty TNT (100 hp) surprisingly well. But I try not to push my luck. A stock trans can handle 60-90 extra hp fairly reliably but no 4wd and/or boosted launches.

As far as what separates a HO from a SO or Cali motor, the biggest difference is programing. There are some other differences but the biggest is programming.

RDyson · 09-03-2008, 11:43 PM

I think the SO motors are 15-1 compression where the HO is 17-1. But the Smarty will make the power potential almost equal--per Bob W.

Randy

***rufushusky*** · 09-03-2008, 11:57 PM

Quote:

Originally Posted by RDyson

I think the SO motors are 15-1 compression where the HO is 17-1.

Really? I am not saying your wrong or anything but were did you hear that?

***nfkfirefighter*** · 09-04-2008, 12:02 AM

news to me also... hmm im going to look that one up very well could be true..

superbird03 · 09-04-2008, 12:12 PM

Thanks for the replies. If you find any supporting information about the compression ratio's let me know. I would be intersted in knowing.

ykdave · 09-04-2008, 12:36 PM

It could be true, but i doubt cummins would build a special 'cali' edition engine.

Like stated above, aside from maybe a few other emissions changes (cat and EGR) they would be detuned also to please the smog nazis

johnyb59 · 09-04-2008, 12:49 PM

here ya go guys try this one: 2001 ISB engine specs