Halfton 12 valve mods.

VMAX

VMAX

New member
I got a half ton 12 valve ram a few months ago. Traded it for a Harley that collected dust for the most part. This truck is my daily driver/street toy/work truck. I have done a decent amount of work on it at night and on the weekends. Mostly fixing conversion issues that were not done, making it better suited for a daily driver, gauges and fuel economy mods.

Truck has a 12mm built pump, 5x018, 188/210, 64/71/13, built tranny, should be around 700 at the wheels. Convertor is very loose. Rear tires are 32", truck has no tach unfortunately.

Truck drives say 50 50 highway and city mostly due to in town driving and traffic going in and out of town daily. All tanks are averaged and filled from the same nozzle hand calculated.

Tank one 17mpg beat on it quite a bit. Got that out of my system.

Tank two 19 mpg still playing with it some, driving like I normally would. Backed timing from 20 to 17 to help with the shakes.

Changed from 373 gears to 318. 21 mpg (thought it would be better but have not done enough highway driving.

Made a winter cover out of big rig mud flaps 22mpg gets to operating temp quick.

Added a high, low beam floor switch (thanks bus) to activate od and lockup at the same time. (I am lazy) plus I figure lockup will be used more = better mileage. Also added 1 quart of synthetic 2 cycle fluid, have not finished this tank yet.........

Next mods, 200 degree thermostat and ice 350 degree boiling point coolant. I will probably pull the convertor and tighten the stator a notch. Do a srt 10 front bumper cover for aerodynamics. Front cover and convertor might be a while all my change is going in the drag truck.

Any other suggestions?
 
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Check for a small boost leak. We got upper 20's going to bowling green when the cam and charger were just installed. That was playing with it the whole way too.
 
CPSimpson said:
Check for a small boost leak. We got upper 20's going to bowling green when the cam and charger were just installed. That was playing with it the whole way too.
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Straight highway i believe the truck will be 30ish. Above I stated 50/50 highway/city.
 
Go to a twin setup with a smaller top turbo something like a stock over a 475 this would help with spoolup driving in the city. tighter converter would also help with the city driving.

what rear axle is in the truck?
 
SKYNYRD said:
Go to a twin setup with a smaller top turbo something like a stock over a 475 this would help with spoolup driving in the city. tighter converter would also help with the city driving.

what rear axle is in the truck?
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This would be nice but waaaaaay down the line. All that cash needs to go to the drag truck. Truck actually spools easily, mostly due to the convertor being so loose. Maybe a spool valve? Truck has stock 9 bolt axle.

YOUNG GUNS15 said:
Is this the third gen half ton that was for sale a while back?
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Grey standard cab 2003 that used to be darren morrisons shop truck.
 
make sure the afc spring is letting the foot travel all the way back in the housing, I know I was losing a few MPG with a stock 175 hp pump spring, acts like a constant pre-boost setting.
 
I looked but maybe I missed it... What delivery valves?

And just on principal... I think we need a picture of said truck lol
 
Not sure on the delivery valves I have not touched the pump yet. I know Garmons diesel tuned it though.

Couple days after I got it.

20121020_182658_zpsaa513d05.jpg


Current fuel tank looking good so far. Even with two street races and a couple WOT blasts.

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Engine bay after painting and cleaning up a bunch of wiring and crap from the conversion.

20121028_162855_zpsff0a2ebd.jpg
 
I'd look into the delivery valves personally on a fuel mileage stand point.

Awesome looking truck by the way. I've always liked that truck.
 
Darren built the pump, I think I would look into timing. I can't remember what it is at after last mods were done
 
My 89 gets about 27mpg highway (slow) 24mpg (fast) and 20mpg in the city. I run 27deg of timing though, I'm light, low, and 2wd. Also 3.07 gears with the OD trans. I am sure my 5x25s aren't helping out any, with DDP injectors I hope to break 30mpg. Aero is huge, so is speed, and so is timing. Those are the main big helps I have found. Use your EGT as a fuel economy gauge, the lower the egt, the better the mpg should be. I know Crabbelle got 30+mpg on his light 2wd with a cam, double OD, etc. Can't find the thread, otherwise I would post it.

I might be showing my nerd side here, but you can always check out Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com for ideas.
 
CPSimpson said:
Darren built the pump, I think I would look into timing. I can't remember what it is at after last mods were done
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thats right garmon tranny and darrens pump.

JQmile said:
My 89 gets about 27mpg highway (slow) 24mpg (fast) and 20mpg in the city. I run 27deg of timing though, I'm light, low, and 2wd. Also 3.07 gears with the OD trans. I am sure my 5x25s aren't helping out any, with DDP injectors I hope to break 30mpg. Aero is huge, so is speed, and so is timing. Those are the main big helps I have found. Use your EGT as a fuel economy gauge, the lower the egt, the better the mpg should be. I know Crabbelle got 30+mpg on his light 2wd with a cam, double OD, etc. Can't find the thread, otherwise I would post it.

I might be showing my nerd side here, but you can always check ot Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com for ideas.
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This truck has practically solid motor mounts. mounts are built very nicely but solid. At 20 degress timing it shook like crazy. at 17 it cut the shaking down 50%. Will probably leave timing alone.

Do you guys think a 195 stat would be safe on a high hp street truck if I ran ice in the radiator? Would head gasket ect be ok seeing high temps winding it up on the street?
 
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