Looking for more fuel on the 1996 12 valve. It's in the 1982 International 1724 I'm planning to use for towing my 34' trailer. I see guys modifying the AFC housing internals to get more fuel. Is this the right way to do things or should one install larger plungers and barrels? I'm considering a slightly larger turbo and injectors. It already had a decent sized air cooler that should flow a good amount of air. I'm thinking I would like to end up at the 400 - 450HP range when done but not sure yet. I'm hoping to bolt a Allison transmission behind the Cummins so I need to make sure the specs of each will compliment each other. Been doing lots of research on the internet. There is a lot to sift through. Appreciate any advice, thank you.
The person to address this question would be member thepumpguysc.
Do you already know what level of HP is safe for the engine internals? This sounds like a recipe for meltdown and/or changing more internal hard parts like pistons and such. When towing a big trailer with a big truck.
Birken Vogt. From what I see on internet so far we should be OK at 400 - 450 HP. The trailer Gross is 22,500 lb so that won't be to much for this truck. I can upgrade head bolts if necessary or at least re-torque existing ones. I'm researching turbo's right now. I have a hybrid Holset HX40/HX35 on my 2001 3500 that puts out pretty good with ok EGT's. Might work with the 12 valve. Also I need more knowledge on the right size and type of injectors to run. I was watching the Thoroughbred Diesel video's showing the different injectors. They were showing some Power Jet injectors that are physically smaller that make more Hp and egt's are lower than 5 by 11's injectors they were comparing to. I hear sac injectors are more responsive than the vco types unless you are wanting way more fuel/power. I'm not committed to anything yet. Still researching. Thanks.
A he351 with bigger exhaust wheel and stock compressor wheel will get you 400 fairly easy with lower exhaust temps. A hx35 with 60 mm compressor wheel would work. Stock he351 or hx35 with a 72 mm turbo under it will do 500 real easy. Watch going to big on single turbo they start getting laggy on the bottom real quick. I just took a 67 mm turbo off my 1 ton, just didn't have the bottom end power needed. Went with a stock he351 and it works great grossing 35,000 on my twelve valve. Going to try a 62 mm with the 67mm exhaust wheel I have on the turbo I just took off. I've done head studs one at a time with real good luck. Timing around 18 to 19 degrees makes a lot more power and is fairly safe with studs. A 215 pump is a real desirable pump to make power. They do retard the timing at wot but you really shouldn't be there pulling a load. 4000 governor springs really make the rpm's more usable. The rest is in the fuel plate and afc housing to control fuel rate. I'm running 5x.012 injectors with good luck on my one ton truck and 5x.016's on another 12 valve with twin turbos. Go on www.competitiondiesel.com and you can probably find all the answers to do it the right way. I'm around 400 hp towing with almost zero smoke but it will probably make 500 at wot not cleaning the smoke up.
There's a big difference between 450 HP for rolling coal and burning tires, or a few minutes on the dyno, vs 40,000lbs gross and using it consistently. That's a pickup engine that sounds like you're expecting to work harder than it's bigger brother. Nothing wrong if you need that power occasionally and will be the only one driving it, but doesn't seem like a good idea in general.
I did a torque plate and a larger exhaust housing, and no muffler (just a resonator) on my '98 F800 service truck, with a 12V, P7100. It was stupid easy to wrap the pyrometer well past 1600°, and I was only 23k weight. And the pyro was added pre-turbo. Some fine tuning got it better, but, I always had a fear of burning holes in the pistons. Best (worst) side effect was that lugging would generate enough black smoke to lose the police car behind me. But, they were cool about it.
Delmer. Occasional is what I am thinking on using available hp. The gross between the truck and trailer loaded would be in the 30 thousand range. Most of our roads up here are generally flat with a few river valleys to pull out of. Just trying to find the balance between the fuel and heat is the trick I guess. I have a young mechanic stopping by today that does the diesel conversions for a living. I'll ask him what my options are. Thanks
Simple mods that make a world of difference on a 12 valve are the AFC mod, a different CONSERVATIVE fuel plate and a 3,000 rpm governor spring kit. The one that really makes them responsive is a change in timing but you have to use the proper tool in place of #1 plunger and barrel. If you do that always use a new lock washer. Stock internals etc are fine if you don’t get carried away with fuel. A bigger turbo helps but don’t get carried away there or you’ll lose some response. HX40 was a very common upgrade back when I was tinkering with them. Look around for what the 12 valve Dodge guys do. Same setup. Tuned just right, and it might take some tweaking, they’ll pull great, have good throttle response and not want to melt down on you. Plus they won’t block out the sun due to over fuel. The last one I tuned up was so responsive you couldn’t shift fast enough, pulled great without overheating and had a nice haze to it. Your CPL should help you find fuel plate choices as well as governor spring kit (gsk) and the AFC kit which is a spring and a couple other bits.
I do timing by locking the pump pin and using a degree wheel on the engine crank. Factory timing is around 12 degrees, 16 is real conservative, I've never had 18 to 19 tear anything up and 25 seems to be to much for a working motor. If you do timing be sure and wash the shaft and gear real good with electric cleaner, they are friction only and they will slip if not clean and tightened proper. Timing along with fueling proper really helps spool the turbo. As far as hx40, I had one on a one ton and they just don't spool quick enough to get ahead of the heat. I'm guessing the truck is geared fairly low, that and having a low first gear lets you get on top of the turbo a lot faster. My f350 grosses 25 to 35,000 lbs a lot and has no trouble mantaining down the road, i just don't beat on it very hard loaded heavy. It basically has 18 degrees timing, 5x .012 injectors 4000 gsk, flat ground fuel plate and afc worked on with a mack rack plug with a stock he351 right now. Timing and governor springs are top on the list for making them run better. Factory motors govern out at a round 2600 but start defueling around 2300. Just about the time they start pulling hard they start to defuel.