I just purchased a 93 W350 4X4 dually,auto o/d with a 109 K miles. The truck has a stinger plus system which I had installed. I wished I would have waited I know I could have saved some money. I'm mainly going to use the truck for a cab over and pull a boat about 6500# total. I would like to make a(reliable) 230hp and 600lb tq. I'v read some of your posts that talk about pins, springs, injectors etc., and I understand most of it. I would like to get your opinions. I'm thinking of getting a gear vender to keep my rpm's low where most of the torque is made however, on many posts here every seems to like the 3200 rpm spring which is just the opposite of what I was thinking.

This is my first post on any fourm and I don't know what I'm doing.

 

a 3200 spring will be a benefit when towing because most the time you want to keep the rpms up like when going up a hill and the 3200 spring allows you to keep the power instead of defuel like the stock spring would do after 2700 rpms

 

As someone who has been visiting this board for a while now (and still doesn't know much) I can say you are in the right place. The guys here are always helpful and rarely hassle anybody for lack of knowledge. Welcome.

 

Thanks, any opinions on gear vender?

 

sorry haven't heard much about them

 

cant speak from personal experience but everyone i know who has had one was very happy. i would have one if i had the bucks and it wasnt so far down the "to do" list.

 

In the the future I'll probably try the 3200 spring first, I just don't want to tow with the transmissions o/d. I live in Arizona everything is up, down and hot.

 

Welcome to the wonderful world of dieseling. Read my sig. and you will find that I have a truck very similar to yours. First and foremost, GAUGES! I tried playing around without them and got totally lost, not knowing whether or not I was hurting my engine. I still need to install some more but that will come in the near future. Exhaust Gas temperature IMHO is as important as any gauge you can watch. It will help to prevent piston melt down. I drilled the exhaust manifold and installed it pre-turbo. There are numerous threads on the subject, just do a search.

 

I have The EGT, Boost and trany gauges from banks and I'm going to order a tach from auto meter that should do it right?

 

yup that should cover her pretty well as far as gauges are concerned

 

Don't worry about being "new". We're all "new" in some area of these things.

I got to 198hp/490tq easily, but I did have to upgrade the transmission so I didn't just spin the torque converter and make heat. The stiff torque converter and modified/set-up valve body coupled the hp to the road. Best thing I ever did to the truck. Five years, no problems.

I did change the turbo housing from my 21cm2 to the 16cm2 non-gated. Then the pump-tweaks and pump timing got the mule really running. No pins, injectors, whatever.

The torque peak is around 1700-1800 rpm. But it doesn't drop off a cliff above that. The danger with low rpm is lugging the engine (lots of load in low rpm). The cummins will run very happily at 2500 in your case, or 3000 with the spring and pull like mad. Having the 3000 rpm spring (3200, some call it), just gives you more flexibility - you can run higher in a gear if you want. Example: when going up a long grade that you can't make in OD because the EGT's get too high and rpms too low, get into direct 3 and run up the rpm to pass the furds.

Of course, the torque-horsepower equation has rpm as a variable; you make higher horsepower at higher rpm. Some folks might just be chasing a higher horsepower number.

I used my 198/490 to drag a 28' fifth-wheel all over the US & Canada. I had no need for a gear vendor rig - I had plenty of power when I needed it. I'd drop out of overdrive if I were starting to lug it there, then drop it again into 2 if I had to (I did, once, on a 18% grade). It would easily handle your 6500# boat and a topper. Why don't you try that first, and go on from there when you believe you need to do it? Much cheaper.

Regards, DBF

 

Thanks for the advise, sounds like the 3200 spring and some pump-tweaks is the way to start. Just before I purchased the truck the transmission had been gone through with a new billet torque converter. I'll check on a different valve body. What is a DTT mod VB?

 

Thats your Valve body. If your truck has both the billet TC and the DTT Valve Body, thats what you need. Other than that, it sounds like you got a decent truck