Cummins QSB 5.9 425->480 upgrade

[ZolexJeff]

This would potentially take place in the twin engines in my boat but let's forget about the fact that this is in a boat for now...what exactly would it take to do this HP upgrade and what kind of costs are we talking about. Also, would the upgraded engines basically mimic factory 480s from a performance curve and fuel consumption POV?

Also, does anyone have any thoughts on what would be the longevity implications (assuming I reprop so that the engines can make the expected 100% loaded RPMs)?

TIA


Jeff

[Snedge]

Basically, Injectors, Turbo, and ECM recal. If You want to PM the ESN on your 425 I can tell you for sure. I can't help much with the marine drive changes needed, if any. ??

[ZolexJeff]

Taking this back online...I PMed Snedge and he responded that the only difference he could see at a quick glance are the turbocharger(s) (ballpark $1,800 each) and a ECM calibration (approx $250).

Not too terrible.

Now I need to research what, if any, 'drive train' improvements I might need to make. This could mean modifications to the tranny (Hurth ZF model 85A-2.0) and/or the props.

For the record, I posted here first about modify the engines because, as far as I can tell, that is frowned upon in the diesel boating community and here I see nothing but support for such efforts.

Jeff

[12vriviera]

Originally Posted by ZolexJeff

For the record, I posted here first about modify the engines because, as far as I can tell, that is frowned upon in the diesel boating community and here I see nothing but support for such efforts.

Jeff

Its more of a curse than a blessing!

[Snedge]

Originally Posted by 24vriviera

Its more of a curse than a blessing!

True words.

[ratman]

Originally Posted by ZolexJeff

Taking this back online...I PMed Snedge and he responded that the only difference he could see at a quick glance are the turbocharger(s) (ballpark $1,800 each) and a ECM calibration (approx $250).

Not too terrible.

Now I need to research what, if any, 'drive train' improvements I might need to make. This could mean modifications to the tranny (Hurth ZF model 85A-2.0) and/or the props.

For the record, I posted here first about modify the engines because, as far as I can tell, that is frowned upon in the diesel boating community and here I see nothing but support for such efforts.

Jeff

you need to check out offshore only.com one guy just built a boat to break the ny to bermuda speed record. 43 nortech with cummins 8.3s. there is a huge thread 37 pages long on diesels for hipo matrine apps right now... what kind of boat do you have and what drives are you running?

i plan to build a 41 apache with diesels beginning of next year with a pair of arneson surface drives.... their are some pretty sharp diesel guys on that thread...rm

here is that big diesel thread on oso, it is an awesome read...http://www.offshoreonly.com/forums/g...peed-boat.html

[ratman]

Originally Posted by ZolexJeff

Taking this back online...I PMed Snedge and he responded that the only difference he could see at a quick glance are the turbocharger(s) (ballpark $1,800 each) and a ECM calibration (approx $250).

Not too terrible.

Now I need to research what, if any, 'drive train' improvements I might need to make. This could mean modifications to the tranny (Hurth ZF model 85A-2.0) and/or the props.

For the record, I posted here first about modify the engines because, as far as I can tell, that is frowned upon in the diesel boating community and here I see nothing but support for such efforts.

Jeff

i would think you could get those extra ponies just by porting your heads and little more fuel. that should get you more hp with out losing any reliability like you would from more pressure/heat from a bigger turbo...

you might be able to get a good jump off the ecu recal. my father had a 70ft huckins sportfish with 12 cyl cats. the original owner did not want to see ANY smoke on take off. the motors ran at 1300hp, my dad had them up to 1550 a side just from cat tech fattening up the fuel curve with the ecu... it still only smoked a for a few secs until it built boost and it ran a lot harder than they way it was. rm

[ZolexJeff]

Ratman,

I'm pushing a 42 fly with Hurth ZF model 85A-2.0 (1.96:1 ratio) so this is no speed demon. Now that I've the boat for the season, I realize that I'm pretty happy with where it is...although I have noticed an increase in GPH and a small reduction in speed as the season has gone on but that is probably just added weight from the addition of toys and such...so I doubt I will be ponying up any bucks for performance enhancements this winter...just aftercooler maintenance and new water pumps.

I'm checking out that other site now...maybe that will spark a renewed interest in performance.

Jeff