Getting over 4k RPM on a 12 valve

You can also rack the barrels, but I'd recommend sending the pump to a shop for that. I'd also recommend having it balanced with upgraded DVs too since they also have a tolerance and will effect balance.

Some rack the barrels and just run without it being perfectly balanced and have good luck.
 
12valve said:
Bumped timing to 28 today, it doesn't pop anymore on free rev, and goes easy over 4200.
It also pulls harder on top. Thanks for that suggestion!
One thing that's noticeable is that turbo lost about 2 psi boost. Is that a possibility?

The fuel plate has been taken out, and I flipped the washer in the afc and cut the afc arm on the front to alow more travel. what else is suggested to do on the pump?

Cornelius, I later remembered that I forgot to post that mod, so yeah it's got ARP head studs, and traction bars, drive shaft loop, and a lowered bump stop. Boost n pyro Gauges I think that's about it.
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Totally normal to see less boost with more timing, more of the fuel is being burnt in the cylinder.
 
Dont have a rack plug. I once shimmed the rack plug and had the engine run away on the first test drive. Stuck plunger Destroyed the engine.
My mechanic says he knows of 3 who've done that, after rack plug. So I'm scared of that.
 
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12valve said:
Dont have a rack plug. I once shimmed the rack plug and had the engine run away on the first test drive. Stuck plunger Destroyed the engine.
My mechanic says he knows of 3 who've done that, after rack plug. So I'm scared of that.
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They've been known to stick with shims. The rack gets caught up on the gap between the plug and case that the washer makes.

It's a $12 part for the correct plug. Definitely worth doing.
 
Ram12vcummins said:
Thanks wasn't sure where to Get. But safe to assume being part of the pump, cummins don't have.
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I mean, it's a Bosch pump, and the second link is a Bosch PN. And anything coming from Haisley has been very legit in my experience (that's where I buy them).
 
A set of bigger delivery valves will help tremendously in your upper RPM fueling capabilities. On the test stand, stock DV's just fall flat around 3000 rpm. If you're looking for a street-able performance DV, get with a 7mm. If you're looking for an all out pulling performance DV, nothing seems to flow up high the RPM's like a full cut DV.

http://powerdrivendiesel.com/product-category/dodge-ram-cummins/1994-1998-2nd-gen-12v/dodge-ram-cummins-1994-1998-2nd-gen-12v-fuel-system-components/dodge-ram-cummins-1994-1998-2nd-gen-12v-fuel-system-components-delivery-valves/ Be sure to use coupon code COMPD5 to save 5% if you decide to pull the trigger on a set of delivery valves.

If you're working on a tight budget, you can cut-down your stock DV's and essentially make your own "full cuts". Those with a $12 rack plug will really increase the fueling capacity of your injection pump.
 
Cornelius: your saying the rack hung at the plug? I had to change one stuck plunger and barrel in the pump at the time I rebuilt the engine, so I believe it was that one sticking and not at the pump front. Is it because the plungers have a bigger turning radius and are not worn out at that point causing them to stick?

Big blue : I once cut my own delivery valves, on a different truck, went a little too far, too smokey.
So what does the 7mm mean? Which spec is it?
They don't seem too expensive though...
 
12valve said:
Cornelius: your saying the rack hung at the plug? I had to change one stuck plunger and barrel in the pump at the time I rebuilt the engine, so I believe it was that one sticking and not at the pump front. Is it because the plungers have a bigger turning radius and are not worn out at that point causing them to stick?

Big blue : I once cut my own delivery valves, on a different truck, went a little too far, too smokey.
So what does the 7mm mean? Which spec is it?
They don't seem too expensive though...
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Ah, that's not what I've normally heard. Typically the rack sticks at WOT because of that. If your plunger got stuck, I'm not sure. It could be what you're saying with pushing to rotate it more (doubtful), or it could be just running it hard with possibly lower fuel pressure (lower lubricity) and it started to wear and catch.

Also, standard DV's have an 8mm OD on the thinner section. This gives you more fuel up high but keeps stock like drivability at lower rpms. That's my understanding. I haven't gotten to play with any yet, but have been wanting to for a few years now.


EDIT:
Will, the sight is coming along nicely. Great work! Super intuitive and easy to find things.
 
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12valve said:
Cornelius: your saying the rack hung at the plug? I had to change one stuck plunger and barrel in the pump at the time I rebuilt the engine, so I believe it was that one sticking and not at the pump front. Is it because the plungers have a bigger turning radius and are not worn out at that point causing them to stick?

Big blue : I once cut my own delivery valves, on a different truck, went a little too far, too smokey.
So what does the 7mm mean? Which spec is it?
They don't seem too expensive though...
Click to expand...

7mm is the size, they run similar to full cuts but idle and run alot cleaner. I've ran these along with full cuts and the truck ran about the same, except alot cleaner at idle and part throttle. Delivery valves are probably the best bang for the buck on a 12v. I don't want to qoute prices but they are available from power driven diesel (bigblue24) for under $300 with no cores needed.
 
So the one you are recommending, Do they have a 7mm high shoulder?

from what ive gathered...
191 shoulder height ~0.5mm shoulder
181 shoulder height = 2.2mm
131 shoulder height = 2.0mm
 
No, the 7mm have a 7mm diameter on the valve/fluted portion, whereas the other ones listed 191, 181, 131 have an 8mm diameter.

To break it down simpler, 191's flow about 60 cc's over stock 181's or 131's. 7mm flow about 90 cc's over stock.

Don't worry so much about the size and/or shoulder width profile, worry about the flow gain both in the lower RPM range and the upper RPM range. Full Cuts will beat everything else flow-wise adding 140 to 150 cc's over stock, but they are flat out too dirty for street use. The 7mm is the largest size I recommend for street trucks because they still offer some lower RPM fuel control yet seem to not struggle in the upper RPM ranges like the 191's, 024's, or similar +60cc DV's.
 
Little update here.
So we had the pulling event and it was a great one. Got first place in the 2.6 class. Outpulled a 6.0 ford only by 5 feet so some more things need to be done.

I went ahead and ordered the 7mm from Power Driven Diesel. They are a great DV! Very controllable low end smoke and a lot high end fueling. Boost went up 5 psi. And now have a lot smoke where as with stock DVs only hazed.

Also ordered the haisley 5k gsk since the Columbus ones struggle with idle setting. Still waiting on delivery.

Also ordered an AFC spring kit by Peak Diesel Power, but haven't put it in.

Now thinking bout a cam... Is it recommended at this stage ? And what will I expect out of it? Stock head n block n Pistons. Its towing some and then pull locally.
 
Just stay with the stock cam, the durability issues don't out way the benefits.
 
I doubt the peak spring kit helps much, it is a lighter spring than the stock one so it will fuel to fast probably. Stretch a 215 afc and run it
 
A lot of people like the Hamilton Cams. The 188-220 is by far the most popular, but the 194-220 is the biggest cam you can fit on a stock setup. It's really close though, and some people that have decked their heads will have to run a thicker head gasket.

Also, it sounds like Will runs an aggressive cam without the extra bearings after using his company's higher zinc count oil.

And when you toss the gov springs in, don't tighten them too much and you'll keep a strong idle. However, the more you tighten them, the higher you'll go rpm wise.
 
So we decided to go bigger, on turbo and fueling,

The plan is to go to either 5x.018 or 5x.020 injectors and an s400 turbo, and put a bushing in there.

my options, (but not limited to) are:
-Cheapest: s471 with 96mm turbine and 1.32 ar $710

-More expensive S471 with 83 mm turbine wheel and need to decide which housing. With 1.1 AR is $1,202, and 1.0 or .9 AR are $1,386

from powerdrivendiesel, hope big blue jumps in to give an opinion on turbo selection and to lower the price on top of the 10% they have this month :)

we do live at over 6000 feet elevation but truck is a manual with 4.10 and is mostly a sled puller.
 
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