HOHN

No Joke. The Cam/fuel setup looks like QUITE the bargain when you consider that you are addressing two of the biggest CTD weaknesses in one fell swoop. Get better breathing AND fix your fuel problems forever!!

I'm curious if the higher pressure helps VP longevity and the FPCM operating temp.

Another thing to consider, imo, is just how much FARTHER a cam will let you stretch the operating range of a turbo. With a better cam and some headwork, you could get more air into the engine at 25psi of boost than at 30psi before.

That creates a chain of beneficial events. Your turbo operated at lower boost, where it's more efficient. Your drive pressure is lower because you don't need as much boost. EGT is lower.



If you REALLY think about it, a cam is about the ONLY modification you can do to these trucks that has NO drawbacks other than cost. Other mods give more smoke-- a cam gives less. A turbo gives more boost, but a cam lets you get more air at lower boost.

With the heads opened up and a good cam, you could probably take an HX35 to 400hp+ and have a LOT lower EGT than someone else would at that level with the same charger.

Don M

Cams do not add peak HP numbers! In some cases, where fuel is way out of range with airflow, you will see a gain.

If a Diesel cam vendor is promising you substantial gains in power, run the other way, hang up the phone, etc.

Cams can move the power band higher or lower in the engines oper range or can extend the range without sacrificing other areas of power.

Direct injected Diesel engines make additional power unlike gassers. Gassers have a fuel AND air charge in the intake runners, DI Diesels do not. Only air.
When you improve/increase airflow in the gasser, you also raise the amount of fuel entering the engine. This does NOT hold true for the Diesel. You only get more air with a performance cam in a Diesel. What you do get is: lower EGT from the increased airflow, lower pumping loss thats directly related to increased efficiency/economy and a wider power band. Wider down low and wider up high.

Peak power numbers are more related to fuel than anything in Diesels.

So, no power claims are made, but you will see the truck is faster and the track times are improved, even though you cant see the gain at a dyno event. Not that the gains are not there and cant be seen by seasoned dyno operator though.

Don~

Don M

Dave Conrad has a Helix 2 cam, a set of Mach 4's, a drag comp and a HX35 with a 12 CM housing. At sea level on Lennys dyno it makes 450 HP uncorrected! His MAX EGT is 1200 degrees. You can hardly force the truck to smoke.

Instant spool up, probably more low end pulling power than anything I have heard of, but it also has 450 HP up top to run strong in that range as well, all day long. NO EGT.

Comparing to my 97 12 Valve that made 348 HP with a #11 plate and a stock HX35 with 1600 degrees of EGT by the time I hit 3rd gear and smoked the freeway out, I would say...we have come a long way baby!

I could not even use the measly 350 HP for a city block, never mind all day long.

Don~

Mike D

So, from what everyone is saying. If you wanted to be in 400-450 hp range a cam looks like it would almost pay for itself, because you're don't have to upgrade the stock charger? Nevermind the benefits of the mech. fuel pump.

I know you would still have to buy the sticks and box to provide the fuel.

Could a Helix 2 with a hybrid or HX40 take you to a clean/cool 500 plus?

shawn085

Would my stock charger do what Mike D is asking? Is the new cam with the fuel pump lobe a Helix 2? Sounds like what dave conrad has is pretty sweet.

HOHN

Well, now let's look at the merit of big sticks, stock charger, MAD ECM and Helix 2 in the 450hp range.

Figure $1400 for a Helix 2 with the requisite springs from Doug. Add another $150 for the 12V mech LP. So you have $1550 on the table.

Compare this to a FASS to fix your fuel problem, and a bigger turbo to get more air in. Say you cheap and get a PDR40 for $1k. Add $600 for a FASS.


So you can either spend $1550 for a bulletproof fuel system and much lower EGT while keeping the superior spoolup of your stock turbo...

..OR...

You can spend $1600 for an unproven ELECTRIC fuel system that needs special filters and has no electric fuel heater, AND a larger, laggier turbo that needs a special donwpipe and such...



Gee, I wonder which makes more sense????



jmo

hemertwv

Not having replaced a cam on these CTD's but having done it on many gassers in the past, how difficult a job is it to get it done, this sounds like a great way to solve a lot of potential long term problems.

Every time the wife takes the truck out for a long drive I am always worried about the LP going south even with a FP gauge.

HOHN

Now THAT's something worth testing.

I would think that a full 40 could do 500 with a H2 cam. If the 35 is supporting 450, there's a LOT more than 50hp worth of EGT left in the difference between HX40 and HX35, I'd like to think.

That, and the lag of the 40 would certainly be less with the cam.



Or, you could just say screw it, and get a SPS66 charger with a Helix 3 cam, and have a rig that will outperform many trucks with twins on a stock cam-- at least up top. I bet it would be pretty soggy down low, though.

Mike D

I think a sweet set up would be, Helix II, HX40/16 with a Mad ECM, Mach 6's and nice fuel only box.

Fishin2Deep4U

I have the setup Don is talking about. The HX35 is actually a PDR 35, so the front end has a slightly bigger wheel. Stock 12cm exhaust housing. This is with a BHAF and running Rip's 4" exhaust and I do have a muffler.

The benefits of the cam go way beyond the EGT relief for me. I did this just for the mechanical fuel system. After 5 lift pumps, I decided that the electric pump was not for me.

So, fuel pressure is constant. Never wavers, never falls, it just works. hard starts from high pressure is not an issue with the VP44. There is a small bleed orifice in the stock overflow valve. So, when the engine is off, all the pressure is bled from the VP. My truck fires immediately, And that means that I have a few psi of fuel pressure at that time. I have 30psi in a few seconds. The issue with hard starts is electric pumps throwing all that fuel at the VP before the truck is started. That's why the factory limited the amount of pressure the stock lift pump made at start-up.

As far as the cam, on my setup, it took out a ton of heat. It also lowered my overall boost a few psi, but this was expected. After I mapped the cam, I can see why these things work so well. Don has allowed the engine to breath better and help it to shed excess cylinder temps. This in turn lowers the drive pressure slightly as there is less energy in the cooler charge. Of course this doesn't creat as much boost and you get a denser, cooler charge. Max boost unloadeed is 34 psi.

And those subjective things that people say and no one can put numbers to are correct. There is much less smoke than the stock cam. Almost half (est) with the comp. Since I went to the Drag comp, I have added some more heat, but will be fixing that soon. Spool is much faster off the bottom. I am guessing 100-200 rpms sooner. And of course the EGT relief...

The biggest thing to note is the quality of the way the truck drives. It is quieter. And the power is very linear. Almost electric. Obviously, it still has that surge from when the charger spools, but it all happens so smoothly, it's unbelievable. Also, this cam stretched out the legs of my little, choked up charger. With the stock cam, it would "nose over" at about 2600-2700 RPM. Obviously, out of air. It will now continue to rev, and just keeps pulling. That's just how effecient the cam is. And a testament to the reduction in pumping losses.

Don has done a great job with these cams. I have never tested another vendors, so I cannot say anything good or bad. But I am a believer in Don's products.

My cam was ground to Dons specs from a new blank. This was not a regrind. I know, I know, others offer that as well. Just telling you how mine was constructed. Also, I decided to go with the stock press on gear. Don will tell you, this took a bunch of time for me to decide. In my application, with the VP44, the bolt on gear was way overkill. I am not running the motor to crazy RPM or going for max HP.

I am very happy with my purchase of the cam and fuel system. If I did this as a first mod, I would have had tons of room to grow and build off of.

Thanks Don!

Dave

Dodge Demon

Thanks for the info Fishin...,could you give us an approx price on whatit cost you for cam and pump.

shawn085

I am still thinking about this mod for my truck. What is it like to tow with. I don't tow much at all but want to keep the option open. How much smoke do you get with the injectors you have now Fishin. I am thinking about the same setup you have, and are going for fishin but will do the HRVP44 if, when my pump dies. What is the price, and did you get any better MPG?

jrs_dodge_diesel

I have replaced one lift pump already, if this new one goes south I want to get this mechanical setup.

Fishin2Deep4U

For pricing, you have to call one of Don's vendors. I made a bunch of changes and that's not factored into the pricing. Also, I did all the work myself, so that negates the labor.

I tow a jetsled almost every weekend. I run a guided fishing business on the weekends. My boat is not very heavy. Under 3K with the trailer and all my gear.

I have towed over 10K over Snoqualmie Pass and it doesn't skip a beat. EGTs are not an issue. There is no need to control them , they are that low. The only issue is the taller tire and hitting OD too soon.

Milage has increased slightly. over a mile per gallon. Boost at cruise is a little lower, but the engine is much more responsive.

In regards to the hotrod VPs, I am not sure that they are worth it. Unless it comes with a warranty, I would just go with a unit from Rip Rook or DDP and get a 1 year warranty. Tapped or not!

Dave

Fishin2Deep4U

How difficult the job is depends completely on your skill level.

I would say that it is involved. There are soem technical aspects that must be followed, but it is pretty much straightforward. This was the first time I had swapped tappets. I had done one other cam swap. BTW, the tappets looked like new.

Getting the right tools, taking your time and doing the job right will take anywhere from a day to 2 days, dependding on how fast you work.

I have air to help get stuff apart, but everything goes back by hand and a torue wrench. You will need a way to press off the stock cam gear if it is to reused. And the ability to heat that up in the family oven to install it on the cam. Also, you need to have an installation kit for the cam swap. Either home made or the Cummins version. Either way, it's a must have. You will also need to be able to remove the fan assembly.

Don's fuel kits come complete. It's a simple matter of removing the stock stuff, including the block off plate and reinatalling the new pump and lines. The hardest part of that for me was cutting the factory line and removing it from the seel line under the cab.

While I had mine apart, I replaced the thermostat, put in new fluid and checked all the bolts in the front end.

Again, if you are good mechanically and have a good mix of tools, you'll be fine. Only thing to worry about is dropping a tappet into the pan. I successfully did just that. It took about 20- 30 minutes to fish it out of the pan. I would greatly recommend you do NOT test your individual stress meter by doing the same.

If you need any questions answered or need another point of contact for installation questions, feel free to drop me a line. I can't give you much in the technical aspects of the product, but I can help you through the simple stuff.

Dave