looking to make 350 to 400 HP

[JPrewitt]

Looking for advice on upgrades to bring my 89 D250 in around 350 to 400 HP.

Let me start by given you some stats: This has been a three year project '89 D250, with completing rebuilt engine (new Cummins head, 7 mm holes) and rebuilt trans (727).
Mods: H&M Fuel Pin (M3), Dynamic Timing Shim, 4 inch Exhaust, HC-35 Non-Westgate Turbo w/ 16 mm housing, 3600 RMP spring, 3 inch Cross Over, 15 PSI Lift Pump, Tuned in VE pump to fit modes (with no to little smoke) all monitored by Edge CTS.

Project Goals: Looking for that 40 mile a day, head turner, daily driver, that will lite 'em up and still get 20 MPG!

When replacing the head due to cracks, I had to replace my 9 mm injectors with 7 mm stock (not a smart move), now I would like to upgrade the 7 mm injectors nozzles with bigger Bosch nozzles, just not sure of which size (5 X .012 or .014). Not sure if I have enough air to run the .014. Any helpful words out there?

 

[Bob4x4]

I would like to see a 1st gen on a dyno at 400hp and no smoke

 

[DVolk]

How does that Edge CTS work on a mechanical engine ?

 

[KOG]

400HP and a 727? There's gonna be trouble in River City.

 

[JPrewitt]

How does that Edge CTS work on a mechanical engine ?

About two years ago Edge developed a EAS kit that works with older/per-computerized engines, data displayed on CTS monitor, petty cool.

 

[Bob4x4]

400HP and a 727? There's gonna be trouble in River City.

The 727 built right has lived behind monster motors..............400hp not a problem

 

[JPrewitt]

400HP and a 727? There's gonna be trouble in River City.

Let me start by saying, I'm not a transmission guru by no means, but 400 HP in a 727 is not out of reach, Plymouth and Chrysler have proven that. The trouble will be with the torque produced by the 5.9 at 400 HP! I understand, as a minimal, an upgraded flex plate and torque converter will have to be in place before my goal can be reached.

 

[JPrewitt]

I would like to see a 1st gen on a dyno at 400hp and no smoke

Bob, if I could get to 400hp, with my setup (plus injector nozzle upgrade) I would be ok with a little smoke! lol It's just that I'm a little old school, and believe that "Lean is Mean!"

 

[cerberusiam]

Depends on whether you want 400 HP for bragging rights, or, a usable consistent 400 HP. One is just rpms and fuel, the other is whole lot more parts and possibly some engineering.

 

[JPrewitt]

Depends on whether you want 400 HP for bragging rights, or, a usable consistent 400 HP. One is just rpms and fuel, the other is whole lot more parts and possibly some engineering.

I'm not afraid to getting my hands dirty, but I am limited on the wallet. What is your thoughts on engineering? IC?

 

[KOG]

400HP is not a problem with a gas engine, but the torque you'll have with a diesel making that power is a big problem. A non lockup converter is going to produce way more heat than you can deal with if you use that torque for more than a few seconds at a time.

 

[cerberusiam]

Unfortunately, it is the wallet that gets hit the hardest. To make it relatively clean and usable that is injector nozzles, pump work and new parts, and turbos. The short comings in the VE pump is getting enough fuel into the distribution head to keep from seizing it up under high flow, the internal pressures are too low and the passages too small after a certain point. Just a big set of injectors will kill the pump if you aren't careful with the right foot.

A blip on the dyno is one thing, running at a constant 350-400 is another thing entirely, probably not realistic for daily use. It is a whole lot easier to tune it to 300-320 HP and use the TQ to move the truck for a fun time, or towing. The transmission you have is going to hurt just about every aspect of the build, just not a good piece for the best effect.

 

[JPrewitt]

Unfortunately, it is the wallet that gets hit the hardest. To make it relatively clean and usable that is injector nozzles, pump work and new parts, and turbos. The short comings in the VE pump is getting enough fuel into the distribution head to keep from seizing it up under high flow, the internal pressures are too low and the passages too small after a certain point. Just a big set of injectors will kill the pump if you aren't careful with the right foot.

A blip on the dyno is one thing, running at a constant 350-400 is another thing entirely, probably not realistic for daily use. It is a whole lot easier to tune it to 300-320 HP and use the TQ to move the truck for a fun time, or towing. The transmission you have is going to hurt just about every aspect of the build, just not a good piece for the best effect.

Good point. So I have not dyno'd the truck, so Im not sure where I stand with HP at this point. Will the stock injectors get me to 300-320?(please note, their the 7 mm injectors)

 

[cerberusiam]

Probably not, they are a little small to get over 300. IIRC, they are pretty much tapped out but the time you pass 260 or so.

 

[JPrewitt]

Let me ask this: What would be the best "leanest and meanest" injectors upgrade in the chase of 300 +HP?

 

[RSchwarzli]

A few thoughts being I sit at 430 HP with a VE engine...

1 - You will need a intercooler. And a good one. Not a stock Gen 1 IC if you want continuous 400 HP

2 - There is a difference between 400 hp stop light engine that will make that power for 10 seconds, and 400 hp up the side of the rockies with trailer 400 hp.

3 - 727.....the tq will be the issue. But again for question 2.... that will say yes or no to that transmission. With no lock up TC, that will build a LOT of heat. And yes, I know a 66-71 hemi came with them....but they werent designed to be towing at WOT all day either.

4 - What is the reason for wanting 400? I use to get annoyed when I was asked this years ago, but I get it now. lol 400 out of a VE engine is not fun to get, but what is the reason? In my case, I roll up the mountains with 12,000+ lbs trailers frequently. And I do 85 mph while doing it. I make use of it for sure. If you want to go ripping stop light drags, well that number must be based on something then. Did you do a 1.4 mile et power calculation based off weight and engine output? Hate to tell you, when your 727 taps out at 75 mph, it takes the fun out of it. (BUT, makes a VERY consistent bracket racer. Use to race my 1990 with 727 and would always be within a tenth!)

5 - Read the costs, steps, procedures, reasons, etc of my multi year build of the 90 and you will know the answers to your questions. As you will see, there is a lot more than turbo and fuel. I learnt that the hard way over the years.

https://www.turbodieselregister.com...tory-and-Modifications-WARNING-LOTS-of-Pics!!


Either way, its your truck and dont let anyone tell you not to do something to it. Its yours to enjoy. But I am just trying to give you food for thought as I have been there....

Goodluck.

Robert

 

[ofelas]

Good points made in this thread.

Right off the bat, think "towing twins".
HX35/HT3B is a time tested combo on 12v trucks and Stone Age tough.

Great powerband, low EGTs and you'd be surprised how much fun medium sized injectors can provide on a street warrior if you tune for mid range.

There's newer technology, but not needed for a 25 yr old street truck.

A big single will get you there, but will be smokier, laggier and have a narrow powerband higher up.

If you want additional utility, an IC 46RH adds OD, and a second gen 47RH further adds lockup, but you'll need some additional pieces/mods for a 47RH swap.

Think usable torque, not dyno numbers.

Nothing wrong with a tweaked VE and a stout 46RH to crack a streetable daily driven 450/1000, but there's a whole lot of reliability you'll need to add in - quite doable though.

"Even" 350/750 to the ground is a whole lot of fun in our relatively light trucks.

Have fun and ask questions of the old timers! It's all been done long before it got fashionable in todays diesel industry!

 

[JPrewitt]

RSchwarzli, Thank you for the reply. 350-400 is just a number, I'm not pulling or working my D250 aka. Lola. I know that that my setup is being limited to around 80 mph tops and Im not getting the MPG that I would like in a daily driver because of the high RMPs running down the HWY.
I read your 1990 post, very nice. I do have some questions that I would like to ask about your Gear Vendor and a couple of our things.

 

[JPrewitt]

Thanks ofelas for the reply. I should have stated that the HX-35 was last years upgrade; moving forward with the chase of more HP will have to be with the HX-35 as my quarterback turbo! I have my quarterback, I need to build my team around it! I think my 1st issue is going to be the limitation of my speed-a-meter and my 727!

 

[RSchwarzli]

RSchwarzli, Thank you for the reply. 350-400 is just a number, I'm not pulling or working my D250 aka. Lola. I know that that my setup is being limited to around 80 mph tops and Im not getting the MPG that I would like in a daily driver because of the high RMPs running down the HWY.
I read your 1990 post, very nice. I do have some questions that I would like to ask about your Gear Vendor and a couple of our things.

350-400 isnt a bad number. For a P pump engine, it is much easier, but that doesnt mean you cant do that from a gen 1/VE pump. And that doesn't mean that you shouldn't chase your goal. You have to enjoy your truck. Your biggest challenge is going to be slippage in a non lock up TC.

Yes, the 80 mph is an issue. lol Mine didnt even get to 80. I would tap out at 75. lol I would average 16.5 mpg stock with the 727. Once I put the Getrag in, I saw 20 mpg and it was up from there once I started adjusting things. Now bob tail I can get 28 at 80 mph. The jump from 24-28 was thanks to the Super HX40.

if you have questions, please by all means! Ask away! Happy to answer them! I will say one thing: A non lock up 727 with a GV will work, provided you are loafing down the highway empty. If you are towing, you will have way too much slippage and heat. But again, if you are building a street truck that isnt running full boost for more than 10-15 sec at a time, it would solve your issue.