The Hydra is great. I love how easy it is to switch tunes, although sometimes it stalls when I do. I always tow with the heavy tow tune. When I'm not hooked up, I usually use #3. To date I have never used 4, 5, or 6.

I would love to see those kind of EGTs when pulling a grade. I see 900-1000 on flat ground, and that was before it started leaking at the pipes.

My RV weighs about 8500#. When you say heavy how much weight are you talking?

 

Wow. $2400 for a set of injectors.

What do you think I can get for a kidney? I know my liver isn't worth ****...

OK guys... I need help deciding what to do here.

I have a perfectly functional set of stock injectors with roughly 180,000 miles on them. I bought the truck at 140,000 from the original owner but I have no maintenance records and I don't know how often the oil was changed. It was bone stock when I got it, except for a K&N filter that was nearly plugged solid. I'm pretty sure I hear one injector a little more than the others on the driver's side when its cold. When its warmed up it sounds healthy.

I've heard that the max reasonable lifetime on a set is 300k. Is that about right? At the very least, since I'm going to be into this far anyway, I would like to change the o-rings this spring.

So the big question is.... what would you do:

- Would you just put o-rings on stock injectors and plan on replacing them in 3-4 years?
- Would you attempt to rebuild the injectors to stock specs yourself?
- Would you bite the bullet now, while everything is apart, and spend $2400 on a new set of 160/80 injectors that might lower EGT's by 100 or 150 on grades?

Keep in mind that my goal is to live full-time in my RV for the next few years starting this fall, while traveling around the US.

 

What does the 'cc' stand for in 160cc/80%? Surely it isn't cubic centimeters...

 

You may be aware of this... or you may not: When switching tunes, do it when your foot is lifted, and wait for a sec - the LED display will blink. This prevents the PCM from getting confusing signals mid-tune switch, and I have never stalled as long as I use this practice.

Towing with 1000 degrees F on the flat? What are they on the flat with no load?

Yes... Cubic Centimeters... but that is the measurement per 1000 shots. If your truck is WOT at 3000 RPM and draining the injectors with each shot:

4 injectors fire per revolution, so 3 (KRPM) X 4 X 160 (injector capacity) = 1920 CCs of fuel are dispensed per minute. That's about 2 quarts a minute... so you're not going to keep that up for long.

Tidbit of knowledge here: 30% nozzles are a modified stock nozzle. 80% nozzles are a whole different nozzle installed on the injector by the builder. 100% nozzles are modified 80% nozzles. Any time you mess with an injector, you void the factory warranty - so the warranty is now up to the builder... and the price will reflect this. Those nozzles don't come out the end, you have to disassemble the injector to get to the nozzle, and that means nothing in there is factory set any more... per se. Once a set of injectors are modified, they need to be flow tested to make sure they are balanced, and any imbalance needs to be either corrected or swapped out... again driving the injector price up for all that time and effort.

I chose 100% for max fuel at top RPM and for lower EGTs across the tach. My tow tune can't blow past 1200 degrees if I tried, and I'm moving along very respectably with a floored tow tune. I might have been happier with 80%, I don't know... but I'm not unhappy now. I don't feel that "Oh I shoulda" that I read about from people who went with 30% nozzles. I'm not urging the 100%, I bought a spare stick to deal with the "customness" of these things - and swapping has helped me after some mishaps (my own fault). With reliability being high on the list, the unmodified 80% nozzle may very well be the holy grail for towing - because you will never ask for full fuel at high RPMs while towing - yet you can get everything you need at realistic RPMs. Burning two quarts per minute in our little 7.3L with the existing cooling system is too much heat to shed. I'm not talking EGTs, I'm talk heat in general - the truck will overheat with that scenario.

 

it is cubic centimeters but it is maximum available fuel volume in 1000 injections events.

 

On a separate note - with that fuel, you can't overdo the air. Air, air, and more air. Seriously... my initial air mods gave me a lot of return for my money - before I spent a dime on more fuel. Air leaks are very bad juju for EGTs, because you're going very far away from the "more air" rule.

 

Id imaging the factory warranty would still go out the window due to the nozzle swap with 80%, but would you still feel it necessary to purchase a spare injector if you went with 80% nozzles? Or would that be considered more of an off the shelf injector since the nozzle was changed and not modified?

 

I'm a cautionary tale... not an example to be followed. I bought the spare after I kept making a mess of my injectors - but it sure is a warm feeling, knowing I have a spare to swap now or in the future - for any reason one would want to swap a stick.

Here's the question that needs an answer: If you lost a stick for any reason, how would you replace it? If you never leave home base, then a bad stick is no big deal. If you are on vacation many miles from home, you are waiting for the UPS man. If it's a holiday... you are really waiting. I've lost crap 600 miles from home on the week of Thanksgiving, and I developed a real attitude about self-sufficiency.

 

I tow about 11.5-12K lbs with the 5th wheel. I say 12K just to be on the safe side. I moved my tunes around and have them as

1. Daily Driver
2. High Idle
3. Heavy Tow
4. Stock
5. No Start

 

They are expensive, but sometimes you get what you pay for in my opinion. I am having a hard time saving up that much money as well, but with stock injectors that are close to 250K miles, I need to save for that day. The stock ones do fine, but when/if one goes I will replace them all, or I will replace them all on my own time in addition to the host of other parts like glow plugs, valve cover gaskets, harnesses, etc...

Rebuilding the injector myself is something new to me and seems to be a trend on the FTE lately. At this point I do not feel comfortable going that far into the procedure quite yet. If I do decide to got a remanned route instead of new due to time, money or whatever I will probably send my injectors to Rosewood to have the ones for my truck rebuilt, for my truck.

We also plan to be living full time in our 5th wheel in a few years after it is set up with all of the equipment we feel it requires to be a self sustaining rig. The truck and trailer will be followed by my wife and dogs in the Subaru and the truck will be parked when we arrive to the camp/living site.

You can also opt for 160/0 new injectors, or take a bit of a chance (much less risk than rebuilding yourself) on some remanned 160/x injectors from Unlimited Diesel or someone else.

 

I've switched tunes while idling at a light and it stalls. I've also done it under acceleration without it stalling.

They usually match the speed x10. If I'm doing 60, 600. 75, roughly 750.

I think I'd be able to rebuild them myself, but flow testing them is going to be tough.

On the other hand, I'm the guy in the right lane staring at the EGT gauge instead of the speedomoter, trying to keep it under 1200. I'd really like to change that.

I'm sure I have air leaks all over under the hood. That's why I'm doing the billet plenums, new boots and clamps, etc.

What if I rebuilt my injectors with 80% nozzles? They are 155cc, right? Would I be able to get away without flow testing them?

Agreed, that's a ton of fuel to go through!

 

This was in the back of my mind too. I sorta regret going with the S&B cold air intake, but it seems to work well enough. Should I go with the same 6637 setup that most people here seem to like?

 

Rich I'm not even halfway through your thread on reman vs new injectors and I've already crossed reman injectors off my list. Not worth it!

 

My .02 on injectors: Air is especially important with larger than AC (160/0) injectors. In thinking about 160-180CC injectors with 80% to 100% nozzles, a 38R should be considered a minimum with a T4 mount 364.5 SXE being optimum . An acquaintance bought this turbo recently and tows a heavy 5th and loves the performance. Said it is night and day. Granted, it replaced a modified Van turbo which is not a 38R. 38R if stock appearance is needed but if you don't need the stock appearing setup and need up-pipes etc, I'd go T4 route.

I run new PIS 175/80 with a Terminator T500 HPOP and stock 38R. This is a wonderful setup overall. Hazes a bit on cold, non-plugged in starts with Gearhead tunes, but once it warms up, it's good. The power is very impressive. Street tunes are more power than I use or need, but towing is spot on. We did a lot of towing last year in challenging terrain going to Yellowstone and Glacier and the power/EGT was great. The truck pulled hard and never hiccuped. With the local rebuilt trans and 6.0 trans cooler, temps were always fine.

I do have a few custom PHP tunes as well. They are a bit more coarse on the idle and part throttle tuning which works great when I need some Prius repellent.

Overall, I wouldn't be interested in trying anything else and definitely don't want a smaller injector. I do want to be clear that the 80% nozzles with emailed custom tunes will not be as clean running as stock injectors, but certainly reasonable and worth the gains. This is my experience, your's may vary.

 

S&B is much better than the 6637. I wouldn't change that.