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Discussion Starter · #1 ·
I just bought a 92 w350 with a 5spd (thinking its a nv4500 BTW how can I tell?) I am going to use this to haul scrap for most of the summer, but I need to make a little more power on the cheap until the funds are a little better. What can I do on stock injectors. Can't afford aftermarket injectors right now so stocks stay in, unless you know where I can get the tips to redo the inj. myself. Can do that at work on the inj. popper. I think I will upgrade the intake right away so it can breathe and gauges are already on the list. So any ideas will be appreciated. Oh not looking to inject anything at least not yet so thats out also.
DS79
 

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You can crank up the injector pump on those pretty easy. Youll get some usefull power there, and with you injectors, and intake...and an exhaust, and youll have a stout rig!
 

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You can only add 100 HP with the stock injectors...

Get a pyrometer for sure, then a boost gauge is highly recommended.

Depending on if it's a 91 or 91.5, you have either a 21 cm turbo exhaust housing or an 18.5 cm turbo exhaust housing. If you have a 21, you will want to find a smaller one.

Intake is good, exhaust is good.

If you cobble together a couple hundred dollars or find an auxiallary electric pump laying around, fuel lift system modifications will give you top end.

Advanced timing and the $20 3200 RPM governor spring will also extend your top end a bunch.

As soon as you get a pyrometer, figure out the fuel screw and learn to play with your AFC. Towing loads, you won't be able to use as much power as you would empty, but you can use the pyrometer to insure that you are using as much as your intercooling will allow you to use.
 

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Discussion Starter · #4 ·
So I should be in the 250HP range then? Not bad would like 300HP once I get the moeny to do it. The truck is 92 so what turbo does that have? How big of a fuel pump do you need? I have some carter ele. pumps laying around would those work? Oh where should I put the pyro, and what are acceptable numbers when towing?
Thanks,
DS79
 

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Pyro probe should mount in the exaust manifold just upstream from the turbo.

Not meaning to go against what Beagle1 said but I think I would hold off on the lift pump mod until you go with the bigger injectors. You do need to get the pyrometer though.

Make sure you are getting full throttle when you put the pedal to the floor. Have someone hold the pedal down and see if there is more movement left when you move the linkage on the pump by hand. If there is, carefully pull up on the pedal (you will need to pull pretty hard) untill you bend it enough to get full throttle.

You can turn the AFC fuel cone so the deepest part is toward the front of the engine. To do this will require the removal of 4 screws on the top hat section of the lift pump and removal of the cap. Be careful when doing this as there is a rubber diaphram under this area and it might stick to the part being removed. Pull the diaphram out carefully and you will find the AFC cone attached to the bottom(before pulling the diaphram, mark its position with a perm.marker)

Turn the cne so the deepest area is facing toward the front of the truck. Carefully reinstall but look down the bore and make sure the fuel pin is not sticking out to block hte cone. (This is the pin that rides on the AFC cone) While you have the top off, see the white gear wheel inside - this is the "starwheel" and tuning this clockwise lessons the spring pressure on the fuel cone so it moves down easier allowing faster fueling. I'd wait until you get the pyro installed before moving this but then you can rotate this clockwise all the way to thee bottom. Bring it back up about a turn.

The fuel screw on the back of the pump will give the greatest increase in power. This is hard to see and access the first time you do it. Again, wait until you get the pyro installed.

There are a few other things to do but wait until the pyro is in. Look at my sig and some of the other guys sigs to see some of the additional stuff.

Oh yea, did I mention you need the pyro installed?:lol3:
 

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Not meaning to go against what Beagle1 said but I think I would hold off on the lift pump mod until you go with the bigger injectors.
My piston lift pump gave me noticeable better top end, but that was with the bigger non-I/C injectors and who knows what kind of shape my stock pump was in when I took it off.

The piston lift pump is at least something to consider if you have to replace the stock lift pump; it's not that much more than stock and will be useful later on, and it's more reliable.
 

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2nd what Paccool said...


And when you try to 'readjust' the throttle pedal, I found it LOTS easier to hold the throttle cable with a pair of pliers and push the pedal down far enough that you can slip it out of the pedal itself. Then, by removing 2 nuts, the whole assy and then put the top into a vise. Makes it a whole lot easier to bend. I actually 'massaged' the part below the top where it's twisted 90*. It's harder to get bent, but it won't straighten itself out when - not if - you romp on the pedal.
When you replace the stock gov spring with a 3200 rpm one, check to see that you get full movement of the lever - you'll understand when you get the top in your hands off the ip. Mine was applying pressure to the spring, lots of it. I readjusted how the throttle lever was situated so I had nearly 90* of movement instead of 45* or so. Just enough spring tension to keep the spring snug, not pulled. Gave me more total movement on the lever. Maybe it's just impression, but I feel like I've got more engine speed control than before. Small movements make a difference now, great at lower speeds.
 

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My piston lift pump gave me noticeable better top end, but that was with the bigger non-I/C injectors and who knows what kind of shape my stock pump was in when I took it off.

The piston lift pump is at least something to consider if you have to replace the stock lift pump; it's not that much more than stock and will be useful later on, and it's more reliable.
Begle, If the pump is giving problems then by all means it should be replaced and the piston pump is a much better way to go.

Even the piston pump can be a problem if the fuel is really turned up. I have the first gen piston pump and when I have a big set of injectors installed the pressure drops to about 4 pounds. I will probably go to an electric setup and install a bypass setup off a regulator so it will maintain about 12 pounds at all times. I was going to do this over the winter but didn't get around to it. So much to do and so little time! :lol3::thumbsup
 

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Discussion Starter · #9 ·
Sounds good, I will do the diaphram as soon as I can. The rest will follow once I can get a pyro. Did I mention I am getting a pyro ASAP ;) Some more questions now, what turbo is on this? 18 or 21cm? What brand tachs work on these motors? One more how can I tell if this truck has a NV4500 in it? I think it does but not sure what or where to look on the trans for ID.
Thanks,
DS79
 

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To ID the trans slide under the truck. If it has a getrag in it which is the stock trans BTW. The name getrag will be cast into the driver side of the transmission.

The turbo if it is stock will be a H1C with a 21cm exhaust housing on it. I would recommend a change to a 16cm housing.

On a tach your limited as to what is on the market. Isspro and westach makes one that will work with the stock Dodge low powered tach input. AutoMeter makes one that hooks to the alt.
 

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Discussion Starter · #12 ·
So where do I find a better housing for the turbo? Will this just be a housing or will I have to swap out the impeller also? Not sure on the trans yet, but will look once it warms up some.
DS79
 

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Discussion Starter · #13 ·
Do you have the numbers on the ISSPRO tach? I think I am going with those gauges so a tach to match would be nice.
DS79
 

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why would he want a smaller housing? is that to just get the boost up quicker so that it has better take off?

if so that should be something i should look for with my m/h swap.
 

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The smaller housing will give high boost levels all the way through the powerband. That means it will give more power all the way through, especially at takeoff.

It will also increase EGT's due to increased backpressure... BUT, in practice on first gens, it decreases EGT's more than it increases them because it supplies more air to the cylinder, which decreases afterburning from our relatively inefficient injection systems.
 

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Discussion Starter · #16 ·
So where do I find a housing cheap? Is it factory equipment on the newer ones or do I need to buy it from somewhere else? Or should I just swap on a better turbo? I haven't pulled with it yet, but my dad said it won't do any better then his 6.5L Chevy w/ the auto. So something ha to be done.
DS79
 

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No better than a 6.5L? Oh man, thems are fighten' words...

The cheapest anybody I know of has them off-the-shelf is $200...
High Tech Turbo

But, they tend to go for well cheaper on this site's classifieds and ebaymotors.com.

While you're looking, you might just stumble across some HX35's that fall within you're budget; they're close to being bolt ins and are really good pieces.
 

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Discussion Starter · #18 ·
I would go to a HX35 if its cheap enough and if it will work better then whats on it. What needs to be done to make it work? What are the benifits of doing the swap? I don't want the truck down for a week or two just so I can have a better turbo. As for the 6.5L comment I told him the same thing, hes a Mopar guy himself, but he will drive anything that is cheap for the farm. I am working on getting him into a Cummins when his Chevy finally dies.
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Your 92 has a 21cm housing on it. Stepping down to a 18cm or 16cm is a bolt on affair. I wouldn't go any smaller if your towing. The 18's were stock on any 89 to 91 CTD truck and the 93 model year. Those wouldn't be to hard to find. I gave the one off my truck away when I installed my 16cm.

If you can find a HX35 cheap it is a small upgrade over your H1C. I wouldn't pay to much for one. The HX35 is a bolt on replacement for a H1C. Just use the H1C exhaust housing instead of the waste gated housing the 35 normaly comes with.

malodin with your M/H swap I would recommend the stock 18cm housing it has on the donor engine. Your going to be towing heavey and that M/H has the frontal shape of a barn door. Your going to need the extra air flow of the larger exhaust housing.
 

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No better than a 6.5L? Oh man, thems are fighten' words... /Q

mines not a great tow rig, probably because of that sucky auto. then again, that truck always runs better when driven hard, so maybe i need a bigger trailer!
 
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