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  • Administrator

HotRod VP44 will need a custom timing for sure being that hotrod pumps are mechanically advanced in timing slightly. 

 

Questions?

  • What transmission do you have?
  • What rear end gear do you have?
  • What size tires on on the truck?
  • What pop pressure are your injectors set too?
  • How many miles on the injectors?

Basically you want a flat fuel table. Like what I've got on my truck is from 0 to 5 PSI is ramping up for smoke control. Then from 5 PSI to 15 PSI is just 100% fuel table. Above the 15 it ramps up again to 150%. This flat zone is built around daily driving but provides that passing power when boost is over 15 PSI then is steps up. This would have to be modified to fit you. Timing wise you going to need to provide for the info above. final gearing, axle(s) gear ratio, etc. All these make a impact on how to tune the timing. Like oversize tires will require a deep retard to spool quickly. Pop pressure affects timing if they are below 310 bar then they are advance in timing and require less. Above 310 bar like me I've gotta add more timing. 

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Ouch!!! If that 35 inch tires on 3.55 gears you not going to get any MPG's. Your final ratio is 3.21:1 to the ground if your rear axle is 3.55 ratio. You will need to change the axle gears to 4.10 to gain any MPG's back. Optimal is between 3.55 to 3.73 final ratio. Like myself I run 245/75 R16 (30.5 inch tires) which gives me a final ratio to the ground of 3.69:1. This puts me right at 2,000 RPM at 66 MPH. Still running 18 to 19 MPG on winterized diesel up here. Again with your setup you need more retarding to get the turbos to spool up because of the tall final ratio. Even running 82 MPH at 2,500 RPMs I still can touch 20 MPG in the summer.

 

On the injectors what does the Quadzilla show for "engine load" full warmed up and in park or neutral? Gives me a bit more clue where you at.

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6 minutes ago, Mongolianthor83 said:

I average 18 miles a gallon ibelieve at 65mph im around 1980 ram

 

Perfect! That right there tells me you do have 4.10 gears. Actually this is a good setup. Your at 3.71:1 final to the ground with 35 inch tires. You can typically double check ratio in the glovebox might have it or the under side of the hood. 

 

 

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4 hours ago, Mongolianthor83 said:

On a side note do you like banks high ram intake? As far as do you feel they help

 

Personally the hole in the manifold is the same and tube feeding the intake horn is the same. Putting that big bulb head on it just make more turbulence in the air flow. True flow intakes like used in racing is the same size both ends and smooth bend.

 

image.png

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2 hours ago, Mongolianthor83 said:

rpm at 67 are 1888 engine

 

Not sure what your ratio is most likely the Speedometer is wrong you might get GPS out give real speed. Like myself my ABS is correct for my wheels and tires. So with 245/75 R16 and 3.55 axle gears I'm at 3.69 for final ratio. If your speedometer isn't calibrated to your tires then all your speed and distance is inaccurate by quite a bit. The only thing is auto do have a slightly taller final gear. 0.68 ratio IIRC.

  • 66 MPH = 2,000 RPM
  • 82 MPH = 2,500 RPM
2 hours ago, Mongolianthor83 said:

engine load in park 1% according to cts2

Engine load is 1% for your injectors are close to final life. This is the ECM defueling more and more trying to hold the engine idle at 800 RPM. When it hits zero the idle speed will start to climb. Typically new injectors are like 7 to 10% engine load at a perfect 800 RPM. If there is little mileage on them you can just pull them out and have them repopped. I'll give a clue stock is 310 bar. Most builder pop at 300 to 305 bar. But in the first 20k miles you might lose roughly 5 to 10 bar in break-in period. At about 280 bar the injectors are bottomed out and idle starts to rise above 800. This why I had my 7 x 0.010 popped to 320 bar better spray, finer mist, better ignition quality. On top of all that extended life span. Slightly less fuel.

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Screenshot_20200201-090429_iQuad.jpg

 

As you can see I'm half way thru my life span on my injectors. Being when I installed the 7 x 0.010's I was at 13% brand new. Now as they aged and worn a bit now down to 6% at an idle. Still hitting the 800 RPM. I learned this trick when I was trying to re-use my old 150k stock OEM injectors and idle was always high like 850 to 875 RPM. But the engine load was ZERO. I had @dieselautopowerbench test my stock injectors I think there was one as low as 260 bar. But floated most at 270 to 280 bar. This is way to low and even now the timing is greatly advanced with low pop pressure remember takes less pressure to move the pintle in the injectors. Early to injection...

 

Like I said about me popping at 320 bar added lifespan to the injector but you need to have a Quadzilla to make it right. Being the high pressure pop open later so the timing has to be made up on the Quadzilla to keep things happy.

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Your fuel pressure should bleed down to 0 a few seconds after shut down. The fuel system does not hold any pressure. You most likely have a small leak some where that is causing the system to loose its prime. While the fuel system looses its pressure it should still hold all the fuel that is in it. A small leak will cause the fuel to drain back to the tank and introduce air in the lines and cause the hard start issue.

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Could be on the supply or the return side. A common area is the return tee behind the stock fuel filter canister. It has the VP return and engine return. A leak after the VP should be fairly obvious with the pressures involved. It could also been pre VP . Anything that lets air in will cause a hard start issue. I have something small on mine that will cause a hard start every once in while. Just have not had time lately to look for it. They can be a tough find at times. What say you @Mopar1973Man, my hero.

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On 3/21/2021 at 4:52 PM, Mopar1973Man said:

 

Personally the hole in the manifold is the same and tube feeding the intake horn is the same. Putting that big bulb head on it just make more turbulence in the air flow. True flow intakes like used in racing is the same size both ends and smooth bend.

 

image.png

 

That is a totally wrong statement. Gail Banks doesn't make parts for fun. If it didn't show increase in air flow, it would have not been built.

Banks has been the only maker of a rear diff cover that works & has been tested in the real world. The guy is wicked smart.

I love mine, & has proved itself. It is really noticeable with the Common Rail head I have on my VP

20201117_184852.jpg

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