hi, im new to cumminses and to all diesels really. i dont have one yet but i am looking to buy one soon. looking to get a std cab long box 2nd GEN 12V stick shift 4x4. couple ?s about em. first, what are some good perf. mods to do im think stacks, #0 fuel plate, etc the usual nothin crazy. lookin to see what kinda mpg people get with these, it will be my new DD. also, thinkin i may lift it idk yet. either a leveling kit and 33s or my buddys got a rclb dodge but a gas job with a 5.5" lift and some 37s and that looks killer. wonderin how a 12V would do with one of these setups.

thanks
nick

 

Welcome to the forum. Before you do anything, a good set of gauges is the first thing to do. After that, I suggest reading around on the forums, you will learn a ton. A lot depends on what you want it for, towing DD or just a DD to have fun in? The 12V have a lot of power to be had for free. As far as mpg go, someone can fill that in here; but if you lift it and add 33's you will have quite a loss in economy.

 

I don't have a lift & I'm turning 33's.

 

Nick, welcome to the website!

It sounds like you have a pretty good idea of what you want to do with your truck when you get it. DTR member 13ALPHA, is giving you some good advice on starting with a good set of gauges. I would have recommended that too.
I would have at least a pyrometer (EGT's) and a boost gauge and I have always had a F.P. gauge on my 96' Dodge CTD 12 valve. Although F.P. is not as critical on a 12 valve as it is on the 1998.5-2002 24 valve engines with the VP-44 fuel pumps, IMO, it is something to keep an eye on and it can indicate problems should low pressures show up.

You asked about mileage on the 12 valve trucks. You can look at my signature and see that my truck is pretty heavily modified, but in town I see about 16-16.5 MPG and on the highway right at 18 MPG. Now that is providing I keep my foot out of the throttle! When my truck was more stock, I could see close to 19-19.5 on the highway, so you should get good mileage with them.

Good luck on your search and purchase.

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John_P

 

hey guys thanks alot! the plan is for it to be my regular daily driver with some occasional towing but light trailers (ATVs, sleds, motorcycle). i have a couple of other lifted trucks and i want to get this one to be a fun but fuel efficient daily driver for when i go to college next year. i dont expect any kinda crazy mileage but 17-18 would be nice if possible. here's my thoughts for mods.

leveling kit
33s on 16s or 17s
6" dual miter stacks
K&N intake
#0 fuel plate
pump turned up
bigger venom injectors
boost, EGT, and FPR gauges in a pillar pod
higher boost via bigger blowoff valve (26-30 psi?)
anything else?

 

hey guys, another ?. you guys had mentioned that i will see a significant loss in MPG on 33s. I was wondering, cause I know that thses diesel trucks typically have pretty high ratio cogs in em, would it be of any gain to swap out cogs say to a 4.11 or 4.56 i know in a gas job it will but how about with a diesel?

 

I am not sure how big the loss will be, maybe 2-3 mpg? Not sure, someone may know exactly. I don't think you'd need to switch gear ratio's, unless you went to monster tires.

 

I am hoping to see 18ish MPGs out of it if possible. This is planned to be my commuter for when I head off to college next year and between home work and class it could see 100 miles a day. 2-3MPGs could be fairly significant at that rate. changing the cogs isnt that big of a deal for me im into muscle cars and building off road trucks and have a full service shop so that is minor if having the proper cogs for the tires will get me the MPGs I need.

 

I run 35 inch tires with a 4 inch lift......economy is nowhere near what the stock guys get.and I'm not saying the tires are the reason why. I get 500 kilometres to 90 litres of fuel. some of the guys I know all stock say they get 700 kilometres. as far as the gears go first in the auto is still way low and rarely gets used unless I put my foot into it. good luck in school

 

thanks. im planning to go manual so that'll help too.

 

If you are after the best fuel milage then I sure would not be using a #0 plate. The #0 plate has no limit on upper end fueling. And will smoke very bad at a idle and up. A better choice would be a #10 or a 100. And A 100 would probably be too much. Bump the timing to 16 to 16.5 deg. Get a good set of gauges and at least a 4" exhaust and you probably won't lose more than a gallon or so MPG. And when ya do stick your foot in it hang on!

 

thanks. im going for good mpg as goal #1 obviously, but id also like to get optimal power too ya know? i dont mind if it smokes when i get into er i like the thought of rollin coal out the stacks. is there somethin in between where i can get good mpg when im easy on er but still roll coal when i give er?

 

18 mpg and reasonable hp... say 400... are not out of the question, depending on driving style.!
You would hate the 4.56 rear end and I would stay away from the 4.10 also, unless going to 35" tires.

RJ

 

If that really is the goal, you'd need to sacrifice lifting it and adding big tires. There is a middle ground of course, but for a commuter like you say, I would not go bigger than 285/75R16's, and keep stock gear ratio, maybe just get gauges, exhaust, intake, and some programmer. It is possible to get better mileage with more power, if you can drive it soft enough. So maybe turn the pump up a little and watch your foot. Give that a try for a while, then decide if you need a different plate or injectors.