NH-250 Supercharged??

[palskidoo]

palskidoo, what class do you run your tractor in? I've grown up in the 7,200lb modified tractor and 2wd modified truck classes with my family. My dad currently runs a tripple BB chrysler modified tractor. The thing I like about the pulling sport is that you get to see a thousand ways to solve a problem... each with unique engineering values, and some with "what were they thinking??" as well! lol I get a kick out of talking to the Super Stock and Pro Stock tractor drivers with double or tripple turbos, or lately blown and turbo diesels with alcohol injection... some seriously crazy setups, but WOW... serious power!!



This year was the first year ive pulled with the turbo on. I pulled 5700# super stock even tho I don't have the require safety upgrades and protective improvements (being my first time they waived the issue) I pulled really well but at 100ft my boost gauge was pushing 12-15 psi which is a higher pressure than the fuel pump i had at the time so the fuel got pushed out of the carb and she dogged out. I have since gotten a better pump and have boosted well into the 20 psi range on a couple stone boat pulls.
P.S. if i didnt dog out on the pull i would have been a serious competitor to the diesel JD's and the thousands of dollars they have in their motors (mines a rebuilt BONE STOCK 175cuin that i bolted a turbo on) Next year shell be back and ready for pulling!!

Next project is a diesel with compound turbos to make some real pressure!!!!

 

[Floridianson]

Im thinking if you think that you can bolt on a turbo and get another 100hp and a truck that jumps plus holds your barking up the wrong tree. I think what you are going to get is your truck that holds the hills just a little longer than before for a lot of money.

 

[Jayco36REQS]

Im thinking if you think that you can bolt on a turbo and get another 100hp and a truck that jumps plus holds your barking up the wrong tree. I think what you are going to get is your truck that holds the hills just a little longer than before for a lot of money.

Never said just bolt on a turbo to get the 100hp... and actually, getting another 100hp (more important is a 100ftlbs of torque), is a guess at a minimum it will take to get this truck to where it will really function. I am perfectly fine with fabrication, modding, tinkering, or completely scrapping the NH250 all together and going another route. I'll figure it out and make it what I want. I figure, worse case, I'll dump the old school engine and go for a modern Duramax and T-1000 Allison like in my 2011 Silverado 1-ton dually. My Silverado has 10x more get up and go even with my 16,000 lb 40' 5th wheel RV hooked on my back!

Where there is a will (and lack of fear to use a cutting torch or plasma cutter), there is ALWAYS a way... Just have to figure out what works for me.

 

[m16ty]

I figure, worse case, I'll dump the old school engine and go for a modern Duramax and T-1000 Allison like in my 2011 Silverado 1-ton dually. My Silverado has 10x more get up and go even with my 16,000 lb 40' 5th wheel RV hooked on my back!

Where there is a will (and lack of fear to use a cutting torch or plasma cutter), there is ALWAYS a way... Just have to figure out what works for me.

You're talking about putting a Duramax in a 5-ton? A 5-ton truck could really benefit from a engine swap but a medium duty pickup engine isn't the answer.

If you want to spend big bucks cobbling up a blower on a NHC-250, have at it. I could spend probably half the money on one and still out pull you though with either adding a readily available bolt-on turbo or just dropping in a 400.

I have no doubt about your skills that you could put a blower on a NHC-250. I just have to wonder why you'd want to.

 

[supermechanic]

NHC-250 lacks the oil cooled pistons common to it's larger brethren.
Heat is your enemy.
Using a 250 block as a basis for a high HP /torque engine would be similar to entering a boxing match with an arm tied behind you.
Cummins made a whole host of engines in the 855 family with cooled pistons.

 

[Jayco36REQS]

For me? Well it's about wondering if I can... trying something different.... or just making it what I want. Playing with blowers isn't expensive when you have 4 or 5 different blowers sitting under the work bench, and access to CNC mills, plasma cutters, mig or tig welders, tube benders...etc.

As for putting an LML Duramax in the 5-ton? I'd hardly say 400HP and 785ftlbs of torque bone stock a non candidate.. not to mention the Allison 1000 6-speed trans. I've seen many LMM Duramax go into the 600+HP and 1,000+ftlbs easily pulling 60,000lb pulling sleds... and even the stock LML could EASILY move this truck more efficiently than the current mill, and better mileage to boot! lol


In my family we never ask "Why do you want to do that?".... if it's something new or unique... it's just plain cool to try! And that my folks is what Hot Rodding is all about!! <Cheers>

 

[Cycletek]

Like M16ty said you may need a motor with more behind it, I got my M813 because I used to have a built Chevy C4500 with the motor up powered to about 850 Hp and the Allison built to handle it. I pulled a 48 foot trailer with it and ran it fairly hard. It was prone to breakage in the axle and drive-line parts. I was looking for a sturdier platform and I am not trying to make a monster truck out of it. I am just wanting to put some more torque in it and I guess I am the "road less traveled" kind of guy when it comes to building power. I have the financial resources and the experience to try something different, I am aware of the NHC's limitations and the fact that most Military truck are gear bound, as far as speed is concerned. I just want to make the power delivery more consistent on an up hill by reducing the amount of times I have to down shift then up shift which is hard on a motor as well. I built my Detroit so it rarely needs to be down shifted to climb a long up hill. I basically want to do the same to my truck, except I think I can get more torque out of it and keep the EGT down by not having a turbo in the way, backing the heat into the motor. The guys at Vortech think my theory is sound and want to be involved in my attempt to make it work the way I hope it may. Because they know that if it does work, it could open up a new vein of business for them. These are a couple pictures of another project with Vortech I was involved with. The Vortech people and I are not strangers to working together, this car was in their booth at SEMA.....I also want to say that I am not challenging anyone around here in their experiences, I regularly watch most threads and even if I think I know the answer, I will wait to see if there might be a better one, I am not above learning new tricks. So if I come off like a jerk, please know that I am just passionate about what I do......and please accept my apologies!

 

[Jayco36REQS]

NHC-250 lacks the oil cooled pistons common to it's larger brethren.
Heat is your enemy.
Using a 250 block as a basis for a high HP /torque engine would be similar to entering a boxing match with an arm tied behind you.
Cummins made a whole host of engines in the 855 family with cooled pistons.

Yep, agreed there are challenges to consider.... like I said, I research variables, and go from there. Heat can be dealt with in many fashions... (aka water or alcohol injection, charge coolers, heck even ceramic coating the pistons... or switch motors completely.

The thing I don't see much on hear so far is people trying new things or finding the real limits of these engines and documenting it. There are a TON of people commenting of "maybe, might, can't, shouldn't".. but nothing much in the way of "here is/was my combo, and he is/was the results". Bjmca has one of the better documented builds so far that I've seen on here with his turbo'd, dump-bed, shortened, dual stack conversion. Very cool truck!

 

[Jayco36REQS]

Cycletek, You by no means sound like a jerk.. in fact, I'm very curious to see what type of path you end up going with Vortech. That's the thing I was trying to say is that there are many way to Hot Rodding... that's the coolest part (at least to me) is seeing how each guy puts his creativity pin on engineering a solution to whatever he sees as the problem. One of the reasons I love pulls and auto racing... Just about every race I see somehting and think "wow that is cool, I never thought about doing it that way!"... One of the main reasons for getting this MV truck was it's something totally different than I've played with before. Something cool and a new learning experience.... not to mention CHEAP.. when comparing them to other forms of motorsport hobbies! lol

I look forward to seeing how your project goes!

 

[m16ty]

The main problem I see with this discussion is some people are coming from the race car world and light truck world and trying to make applications in heavy military trucks.

If you've ever had a 855 Cummins apart and compared it to a Duramax you'd see why a Duramax swap into a 5-ton is a bad idea. I've seen some Duramax and 5.9 Cummins pulling trucks make some massive HP but there's a whole lot of difference pulling a sled 300' and driving the same truck down the road loaded for any distance. I could see a Duramax swap into a deuce but not a 5-ton, way too much truck and not enough motor. There's a reason they don't put Duramax engines in new big trucks.

I say go for adding a blower or a Duramax swap. Just be sure to post the results here.

 

[Cycletek]

Actually I have built a Detroit Diesel and added a turbo and wet intercooled it in a 40,000 pound combination, so I have experience in power adding a heavy vehicle. The 8V71 I built was not a t motor either, so I was conservative with the boost only 7-9 pounds of boost depending on ambient temperature, the magic was cooling the inlet charge to control EGT at exhaust manifold. I ran the turbo un corked and the EGT went down, but man it was loud, even 40 feet away behind me. So I muffed it and lowered the inlet temp and got the EGT way down even with a long up hill pull. I put a mister spray bar on the radiator just in case, only had to use it once, in 110 degree ambient pulling a 9 mile up grade. Unfortunately I do not have access to a Dyno that would fit either of they vehicles, all I can say is before I could barely pull 42 MPH now I pull 55-60 up the same grade. The only reason I even opened up the engine is because Detroit like to be run kinda hard, so I made sure it was in sound enough shape to handle the extra pressure, it is actually quieter under boost, a lot less diesel knock.

I want to eliminate the temperature hold back of the turbo and put some boost in it through a wet intercooler using a Vortech supercharger with a minor amount of boost again. I am not building a monster truck like I stated before. Just gonna move a bit more cooler air through it under a little pressure and get rid of the trash can muffler and put a long Donaldson in the stack location to let it breath a little better. I just want it to hold the gear better on an up hill, not faster just without having to jack around the shifter so much, It do not care if it makes even one more HP than it should just want to raise the torque number a bit, just like my bus........

Good evening Gentlemen!

 

[jwaller]

you actually don't want low end torque via boost on diesel engines. It's called lugging and it's very bad for the engine. Turbo's are very well suited for diesel's especially the old ones that we have in our MV's.

 

[Floridianson]

Turbo,different injectors (fuel trned up) on a PT set for a turbo motor would be doable without a compleat rebuild. Rebuild new LPF liners cut in block, possible piston change to lower compression and the same as above on PT and injectors, different timming.

 

[Cycletek]

http://www.youtube.com/watch?v=YqkY8GB9VW8

This is an example of going a little too far, this is Mike Harrah, he is one of my customers. Mike is a property developer here in southern California and he has A LOT of money. But this is a Diesel using supercharged boost successfully........

 

[jedawson1]

Cycletek. It looks like you have the means to replace the motor if your idea fails. I like the idea and am glad to see some out of the box thinking. It's one thing to tinker with your daily driver when it's all you have, but for most of us these are toys and we can play with them how we see fit. Don't lose your imagination cause I want to see how this works out. I'm avoiding the turbo because of egt's and known risk having to monitor temps. If this idea works and doesn't have the inherent heat risk I will likely copy your idea.

 

[Stalwart]

First of all a centrifugal supercharger builds its boost at higher rpm's, not at all linear boost delivery. 4 lbs of boost at 1100 rpm would give you about 16 @ 2200. This is where a turbo works well on a Diesel, you can get boost down low near the torque peak of the engine around 1400 rpm. The turbo gets its energy dependent on exhaust gas mass flow, not a function of rpm. Will it work, yes but you must use the higher rpm's to make good boost and power. For a Diesel to make good low end torque a positive displacement blower would be a better fit. Look what Gale Banks Engineering is doing in his high performance marine engines, especially for his positive displacement supercharged engines:

http://www.bankspower.com/fridaynig...nks-Sequential-Super-Twin-Turbo-Marine-Diesel

 

[BillabongKong]

I have been following this thread as well.
http://www.steelsoldiers.com/showth...M939-Series-Trucks-With-Allison-Transmissions
I dont know if it has been mentioned here before, But some of you guys might find it interesting. Along a milder note I found the idea of water/methanol injection might be a good balance of increased power and economy. But I wouldn't want to taint this thread by even speaking the word "Economy" !
Has anyone ever brought a pulling sled to an MV rally? It might solve some of this discussion.

 

[m16ty]

I'm still trying to rap my head around what the advantages are to putting a blower on a NHC250. Cost isn't one of them because you could probably find a good takeout 400 for less money than you can supercharge a 250. I don't see performance being an advantage because you can add a turbo fairly cheap and provide more boost than the rest of the engine can stand. So want's the advantage to going to the trouble of putting a blower on a 250?

You can build a 250, if you throw enough money at it, that will handle all kinds of boost. Cummins has already done it though. Any 855 cid Cummins will fit into a M939 truck with little modification and they can be had up to 600hp in stock form. If you feel the need to supercharge a Cummins, at least start with one with oil squirters and a intercooler so you're not backed up against the wall before you even start.

 

[bearboley]

275 nhrbs iron lung cummins. Factory supercharged no turbo 1940's,50's vintage. its already been done.

 

[350TacoZilla]

Ok guys newbie chiming in here, if everyone sat around and said no you can do it easier this way or no you shouldnt try that we would never have gotten half the inventions we have today. I also have to say to the guy that thinks building boost down low is lugging and engine you must know 0 about boost, if you build boost at low rpm the engine will never be out of its power band and will never "lug" . I have seen a few high hp truck falls under the turbo and start lugging but never a SC 10lbs of boost at idle is 10lbs more than a turbo will give you and you can play with pulley diameter until you are purposesly running at max boost at a lower rpm where these engine like to be anyhow.I say go for it with the blower add a intercooler and then start playing with fuel rate.

I currently have a 6.2 diesel truck I plan to supercharge with a small eaton M90 blower, my feeling is if it supports 3.8L @6500rpm it can support up to 7.6 @3250rpm so my 6.2 should be fine since I dont like to spin it up past 3500.