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Hey guys...
New here, I spend most of my time over on moparts.com. Built my 71 Demon over the last 12 years, and I recently bought a 91.5 12 valve regular cab auto. I got her for 2500 bucks, and basically rebuilt the rearend, put 7 u-joints in it, replaced rear drums, wheel cylinders, and shoes, front brakes and 1 rotor. Master cylinder, and brake booster. The truck sat since 06. It doesnt leak any oil, trany shifts great, and when I serviced it, it was decent. Had a little aluminum in it i guessing from the converter. Its a BONE stock truck with 194K on it. Im a MOPAR nut and bleed hemi orange, and LOVE the cummins. Ive worked a a dodge shop for 8 yrs, and I recently got promoted as service manager at our sister GM shop. Thats where I got a set of 08 GM 3/4 ton wheels that I turned the centers out bigger to fit the bigger dodge front hubs.
Im planning on some basic upgrades/mods. I have read up on here how to turn the pump up a bit, adjust the diaphram, and make a little smoke. I have a question though. How far do I go before I push through the converter. Its a 4 speed non lockup trans. Also I know this is an SPEC truck, but I cant find my TACH plug end. I found a 3 wire round bullet style plug end, but it doesnt match any I have in my service manual. Can anyone on here help me out a bit. I want a little more power, but nothing excessive thats gonna make the truck unreliable.
Ill post a picture when I get this new site figured out.
Im gonna clone it to a 80s MACHO power wagon. I had a white and yellow 360 auto MACHO truck back in the earlie 90s. Wish I still had that girl.
KAsey
New here, I spend most of my time over on moparts.com. Built my 71 Demon over the last 12 years, and I recently bought a 91.5 12 valve regular cab auto. I got her for 2500 bucks, and basically rebuilt the rearend, put 7 u-joints in it, replaced rear drums, wheel cylinders, and shoes, front brakes and 1 rotor. Master cylinder, and brake booster. The truck sat since 06. It doesnt leak any oil, trany shifts great, and when I serviced it, it was decent. Had a little aluminum in it i guessing from the converter. Its a BONE stock truck with 194K on it. Im a MOPAR nut and bleed hemi orange, and LOVE the cummins. Ive worked a a dodge shop for 8 yrs, and I recently got promoted as service manager at our sister GM shop. Thats where I got a set of 08 GM 3/4 ton wheels that I turned the centers out bigger to fit the bigger dodge front hubs.
Im planning on some basic upgrades/mods. I have read up on here how to turn the pump up a bit, adjust the diaphram, and make a little smoke. I have a question though. How far do I go before I push through the converter. Its a 4 speed non lockup trans. Also I know this is an SPEC truck, but I cant find my TACH plug end. I found a 3 wire round bullet style plug end, but it doesnt match any I have in my service manual. Can anyone on here help me out a bit. I want a little more power, but nothing excessive thats gonna make the truck unreliable.
Ill post a picture when I get this new site figured out.
Im gonna clone it to a 80s MACHO power wagon. I had a white and yellow 360 auto MACHO truck back in the earlie 90s. Wish I still had that girl.
KAsey
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From: Southern New Jersey
Welcome to dtr the 91.5 trucks don't have the factory tach harness. You need a pyrometer at least before you start turning it up. What are you going to use the truck for that is a big deciding factor in what mods will be best for you. The stock engine will push through a stock converter. I love old mopars to I have a 71 duster that is waiting for some attention.
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Thanks guys.
Well the truck is primarily for towing the Demon to the track, and I kinda knew the 300 hp mark was fire time in the converter. I plan on going through the tranny, and going with a stepped up converter with billet housing, and brased fins.
How much HP can I expect to gain? I also dont want to kill the mileage too bad. It gets 18 in town and i have gotten 23 down the highway.
Kasey
Well the truck is primarily for towing the Demon to the track, and I kinda knew the 300 hp mark was fire time in the converter. I plan on going through the tranny, and going with a stepped up converter with billet housing, and brased fins.
How much HP can I expect to gain? I also dont want to kill the mileage too bad. It gets 18 in town and i have gotten 23 down the highway.
Kasey
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From: Southern New Jersey
Hp gains all depend on how much money you want to spend. My truck was pushing through the stock converter with just a few minor mods no where near 300 hp. I think it all depends on the condition of your converter. The aluminum that you found in the pan probably didnt come from the converter I dont think there is any aluminum in there. I have gotten similar fuel milage with the mods I have. You can control your fuel milage alot with your right foot!!!
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From: West Palm Beach, Florida
Those are pretty good mpg's for a stock tranny... oh wait, you have a stock engine too! 
Not for long though, right? 
HP gains depend on how much fuel you want to throw at it. On a stock but tweaked pump, with stock injectors and turbo, I'd say somewhere around 250 - 300. Probably closer to 250.
Mpg's have more to do with your right foot than anything else. There are guys on here who have loads more mods and making much more power than me but get better mpg's
. Mainly stick shift though, they're getting it to the ground better.
So depending on what you want to do to the truck, and how much you want to spend, depends on how much power you can make. You seem to have defined what you want the truck for, but not necessarily what your ultimate HP goal is. And let me tell you, once you start bombing, you ain't going to want to stop! Yeah, you'll tell yourself, 'oh, this is just my tow rig...' Uh huh, you just wait, you'll end up having a hard time choosing which to drive, the Demon or the truck.
Not for long though, right? HP gains depend on how much fuel you want to throw at it. On a stock but tweaked pump, with stock injectors and turbo, I'd say somewhere around 250 - 300. Probably closer to 250. Mpg's have more to do with your right foot than anything else. There are guys on here who have loads more mods and making much more power than me but get better mpg's
. Mainly stick shift though, they're getting it to the ground better. So depending on what you want to do to the truck, and how much you want to spend, depends on how much power you can make. You seem to have defined what you want the truck for, but not necessarily what your ultimate HP goal is. And let me tell you, once you start bombing, you ain't going to want to stop!
Yeah, you'll tell yourself, 'oh, this is just my tow rig...' Uh huh, you just wait, you'll end up having a hard time choosing which to drive, the Demon or the truck.
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Well thats also a BIG problem with me. I just got done building my 408 stroker for the Demon, Its got brodix heads, and about 10k in the block, and rotating assy. I didnt even get out of the shops parking lot, and I was sideways. SOOOOO, Im pretty bad for the right foot syndrom. As far as EGTs, what is the "bad" number? I have rebuilt many 12 valves, but never owned one to play with so I just dont know the numbers. I worked at a cummins/7.3 ferd shop, and everything was stock rebuilds. I plan on putting a pair of WEED burners that are 6" stacks under the rockers and past the box turned at a 45 degree angle. Ill use 3" pipe to go from the factory head pipe, to the burners.
Kasey
Kasey
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From: West Palm Beach, Florida
Use 4" tube, your truck will love you for it. 
As for a bad EGT, it depends. Sustained, 1250° seems to be the magic number. But for a short burst, (like a 12 second 1/4 ) 1600° is not unheard of.
As for a bad EGT, it depends. Sustained, 1250° seems to be the magic number. But for a short burst, (like a 12 second 1/4 ) 1600° is not unheard of.
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Those are pretty good mpg's for a stock tranny... oh wait, you have a stock engine too! Not for long though, right? HP gains depend on how much fuel you want to throw at it. On a stock but tweaked pump, with stock injectors and turbo, I'd say somewhere around 250 - 300. Probably closer to 250.
Mpg's have more to do with your right foot than anything else. There are guys on here who have loads more mods and making much more power than me but get better mpg's. Mainly stick shift though, they're getting it to the ground better.
So depending on what you want to do to the truck, and how much you want to spend, depends on how much power you can make. You seem to have defined what you want the truck for, but not necessarily what your ultimate HP goal is. And let me tell you, once you start bombing, you ain't going to want to stop! Yeah, you'll tell yourself, 'oh, this is just my tow rig...' Uh huh, you just wait, you'll end up having a hard time choosing which to drive, the Demon or the truck.
Not for long though, right? HP gains depend on how much fuel you want to throw at it. On a stock but tweaked pump, with stock injectors and turbo, I'd say somewhere around 250 - 300. Probably closer to 250. Mpg's have more to do with your right foot than anything else. There are guys on here who have loads more mods and making much more power than me but get better mpg's
. Mainly stick shift though, they're getting it to the ground better. So depending on what you want to do to the truck, and how much you want to spend, depends on how much power you can make. You seem to have defined what you want the truck for, but not necessarily what your ultimate HP goal is. And let me tell you, once you start bombing, you ain't going to want to stop!
Yeah, you'll tell yourself, 'oh, this is just my tow rig...' Uh huh, you just wait, you'll end up having a hard time choosing which to drive, the Demon or the truck. I can get 4" but dont have a 4" bender. I can buy some 4" elbows, and ill just tig the stuff together. Ill have a little clearance issues, I hate exhaust hanging way low.
Kasey
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I can get 4" but dont have a 4" bender. I can buy some 4" elbows, and ill just tig the stuff together. Ill have a little clearance issues, I hate exhaust hanging way low.
KAsey
Oh and thanks guys for the kind replys.
KAsey
Oh and thanks guys for the kind replys.