I have been viewing the posts at this forum for a few days and noticed a couple of guys are running the STS Turbo system on their Hemi trucks. I have been interested in this system for quite some time. I have an '05 Power Wagon that I bought new last May. This truck is my daily driver and I use it for work, hunting and hauling my 5th wheel trailer (truck + trailer = approx. 16,000#). I doubt that my truck will ever see a drag strip or a hot rod racing in the other lane, but I feel that forced induction would be just as useful in my application as it is for someone just wanting to go fast. When towing my 5th wheel I will average between 6 mpg (heading to the mountains, gaining elevation, headwind) and 10 mpg (heading home to the prairies, losing elevation, tailwind). I can maintain 60 mph almost all the time, but that results in downshifting on pretty well any hill. On the steepest and longest hills I am down to 2nd gear with my foot to the floor and the engine turning 5500rpm. I think forced induction will allow me to use less throttle and experience less downshifting while also achieving better fuel economy and less stress on the engine (and me). This would require a forced induction system that achieves peak boost at a fairly low rpm (say 3000 or less).
I contacted STS last fall about a system for my truck, but at that time they didn't have a tuning solution. They suggested I try some of the internet forums to see what might be availiable. I did search a little and post a few questions, but it didn't seem too practical that I would order and install the kit from STS and then drive my truck (if it would run properly) to some speed shop possibly thousands of miles away for a tuning session on a chassis dyno to sort it out. I want to find a well engineered/complete with tuning package that would require only minor tweaking and would provide factory quality, reliability and driveability.
I looked in to the Paxton centrifugal supercharger system as sold by GS Motorsports. There is a fairly local shop (2 hour drive) that sells and installs this system. It appears to be very complete and they promised excellent results in terms of driveability (no engine codes, no quirky running characterisics). I even talked to a customer that had installed this system on his own Power Wagon and he was very happy. However, all my research tells me that a centrifugal system doesn't achieve peak boost until near redline. The dyno sheets posted on both GS Motorsports and STS Turbo Systems websites show that the turbo system makes better peak numbers, but more important to me the turbo system makes much better mid-range numbers.
For you guys that are running the STS system;

Did you do the install yourselves?
Is there a tuning solution provided with the kit (reflash or piggyback)?
Is custom tuning necessary?
Are you happy with the driveability?
Am I on the right track with my comments above?


Any comments would be greatly appreciated!

 

The STS or the GSM will not work for your application because they are not recommended for towing. When a PCM reflash is available then I would suggest the STS since it can have full boost by 3K rpm's. Currently the piggyback is the only solution but it lets you add fuel only at WOT so going up a hill at part throttle you would hit boost very quickly but rour A/F would still be 14.7 : 1 which is bad for the engine under boost and with load.

 

I have to agree. I'd stay away from forced induction with a 5th wheel. If it was from the factory and had built in fuel controls to keep EGT's down at part throttle, that'd be another story.

 

Thanks for the advice fellas. I'll remain patient. Maybe a proper solution will arrive in the future.

 

Hey guys, would a Superchips remote be able to help with that? i would have thought that the extra edge and retuning of shift points would be able to hook him up and get the truck just right.

 

Sounds like you should have went with a cummins turbo deisal. Have you thought of bolt-on's could get over 300HP and around 375-400lb of TQ for about 2k or so without any real tuning needed.

 

You can always get a little juice, lol.

[IMG]local://upfiles/35047/746ADC703E504A9D98F57D26F3DAEB34.jpg[/IMG]

 

have you considered supercharging it? kenne bell is developing a kit, and i think powerdyne has one. this would be your best bet for towing purposes. no turbo lag, and the boost is there when you need it. any forced induction though, you will probably have to beef up your internals. i'd check into it though if i were you.

 

Kenne Bell will probably be another 3 years before they releas anything. The only supercharger currently available is the GSM but it is a centrifugal unitl so it will not have full boost until 6K rpm and at part throttle while under boost it will havea 14.7 a/f which is bad for the engine under load(towing) conditions.

 

Thanks again for the comments fellas.

As for the cummins diesel, it's not appropriate for my uses. If my truck was used primarily for towing and only occasionally for other uses I could justify living with the diesel (very heavy, very expensive). However, I live about 2 minutes from work and only put about 15,000 miles a year on my truck. I use my truck for numerous hunting and fishing trips and other off-road excursions. I make about 4 or 5 trips a year where I am towing my 5th wheel more than 2 hours one way. I bought the Power Wagon because it comes from the factory with room for 35" tires, front and rear lockers, 4.56 gears, electronic disconnecting front sway bar, 12,000# Warn winch and full skid plating front to back. All that is had for about $2,500 (CDN) additional MSRP over a QC Laramie with a Hemi. Try pricing the above in the aftermarket and see what it adds up to. Even if the Power Wagon was availiable with a cummins, which it isn't, I doubt I would choose it. With the amount of miles I drive in a year it would take me many many years to recover the extra $7000 - $8000 up front cost for the diesel, even assuming a 20% to 30% mileage gain. Also the weight of the diesel is a significant problem off-road.

Life is all about compromise. I wish I could have the Power Wagon's features with the Cummins' power, but without the additional cost and weight.