Never enough

[Nickbf2504x4]

So i hit my first big grade since my turbo install today...

See Sig for truck details.

Im crusin at about 80 MPH at 2200 RPM's with the propane on and up the hill i start...the boost gauge climbs to about 4-5 lbs and the EGT's quickly follow suit, my speedometer on the other hand did quite the oposite i wouldn't let the pyro go over 1000* and I had to get out of the throttle. my tach dropped to about 1800 and i limped over the hill at about 55-60 in OD...this is with no load just me and my LPG flowing.

*Note boost never got over 4.5 lbs. Does this sound like pretty bad performance to anyone else? or ami i just i wonder if i wouldnt be better of with 4.10's because i would be at 2500 RPM's and probably be able to maintain the speedlimit all the way up the grade...shouldn't i be able to keep the speed limit on any highway with no load at sea level? bad IP? What do y'all think :***:

 

[Mikes91]

I dunno what kind of grade you're climbing. I know some that I climbed in eastern California were pretty stout... especially with 6000+ pounds on my back.

I think you're expecting a bit much from 3.55s in overdrive. Should have probably taken the hill out of overdrive at around 65-70mph, whatever keeps your RPMs reasonable. 80mph is NOT where these trucks were made to live. Back in their day, 55-65 was the speed limit on the interstate. Our trucks handle those speeds well, even loaded.


Mike

 

[Nickbf2504x4]

ok so im a little but thats just what i wanted to know... i never run my truck over 2500 RPM's though...i probably should have rowed into 4th and let her sing...so even on a grade in OD un loaded it normal for me to only push about 4 and a half pounds of boost

 

[fiverpuller]

Boost is based on rpm and load. If you were only at 2200rpm then 4.5 boost sounds about right compared to my banks turbo(s). If you want to "hot rod" it you have to climb the rpms a bit. Run her up to 3000 rpm in 4th and you should see around 10 psi (on grade) one would think.

 

[towcat]

nick-
keep in mind not only do you have 3.55's in the back but those 285's aren't helping much either. Bottom line is that you were outside of your powerband. try 4th direct next time you start to bog. My '86 F250 4x4 had no problems with the hills naturally aspirated. Problem is, even with 3.55's, it liked another gear on flat ground. Oh yea, the tires on that truck are 33x12.5x16.5
One more thing.....
2500 rpm max is ridiculous. your powerband tops out at 3000 so in essense you are short changing yourself. Anybody who has survived a ride in my car carrier will swear when I hit the freeway, the tach is pinned on the governor. That's with 4.56's in the back. I used to have 5.13's.....even if you don't want to run it pinned, top out at 3200 and you will still have all the power you need. These motors like to rev. Lugging them is the quickest killer on our motors.

 

[6point9diesel]

Before all the mods to my current rig I ran 3.55's ,4 speed, 4 wheel drive. My tired old 6.9 n/a wouldn't bat an eye at a hill doing 70-75. My revs would probably be a little higher than yours, but you're running propane and a turbo.

What grade of incline?
Did you get any smoke? If so, at what point during your climb?
Do you notice changes in your in town driving with the turbo?
Does it behave different on the hill without the propane?
Is it possible you got into some bad fuel somewhere?

Paul

 

[beretzs]

Nick, I second what TowCat is saying, you NEED to push the engines up in the 3K range if you are struggling pulling hills. I have a Banks, and can make 12 psi, unloaded at about 26-2700 Rpms and at that RPM range the truck will climb all day long. Don't be scared of the RPMS. They are your friend, you get better cooling, and more HP, those are the ideals for climbing hills. I like you, used to be scared of running too high of RPM's, but if I am think I am lugging at all, usually I kick it out of OD and the truck will power through most any hill woithout too much trouble, LOADED. Scotty

 

[Nickbf2504x4]

awesome...you learn something new everyday thanks guys time for a test drive

see im still a youngin but it seems like if peak torque was down around 1800 RPM's thats where'd you'd want to be climbing but i guess not!

 

[beretzs]

1800 is where pk tq is, but not peak HP, I totally don't wanna get mixed up in this, but the upper RPM range seems better for pulling hills, more coolant flowing, more air moving through the turbo, more HP, and so on. I know it is a stretch to break the mold and run them up high, but once you do, you will see, the power is there and boost will rise. Crank up your fuel, you can always back out of the go pedal is you need to, it is better to have and need it than to have and not be able to use it, well you know what I am getting at, and if you are pre turbo, you can run up to 1200, 1000 is very conservative.. Just my opinion, run the truck like you are mad at it, once you get into the big hills, and the truck will shine. Try using the 133/241N as a test bed for pulling hills, it goes up really quick. Before I did my IP/Injectors, I was lucky to crawl up it at 55mph, now with the new stuff, I can set the cruise and let it climb it at 70mph, just adds boost and rolls up with no problem. Except for the darn tolls. Anyhow, hope this helps. Scotty

 

[Nickbf2504x4]

scotty what is your tach reading with CC on at 70? wheres the 133/241N? thanks man

On edit: i see that roads down in your neck of the woods...i will stick with the grapevine its about 30 mins away! haha

 

[The Warden]

One more thing.....
2500 rpm max is ridiculous. your powerband tops out at 3000 so in essense you are short changing yourself. Anybody who has survived a ride in my car carrier will swear when I hit the freeway, the tach is pinned on the governor. That's with 4.56's in the back. I used to have 5.13's.....even if you don't want to run it pinned, top out at 3200 and you will still have all the power you need. These motors like to rev. Lugging them is the quickest killer on our motors.

WHAT HE SAID!!!

I went on a trip to southern California with a guy from TDS (he needed to bring a truck up to this area from his parents' house, and needed someone to drive his 6.9l back, and I got a free trip to see my dad out of it) a couple of years ago. This guy was firmly convinced that the 6.9l should NEVER go above 2000 RPM, to the point where he was in top gear by about 40mph vehicle speed...with 3.31 rear end gears and a ZF5. He didn't have a pyro, but I don't want to know what his EGT's were going up the Tehachapis. When I got behind the wheel, I drove it like I would drive my truck...and there was a LOT less smoke, quite a bit more power, and the truck did better on fuel consumption as well.

I had actually known this before, but this proved to me beyond a shadow of a doubt that towcat's 100% right on that. These engines may like to cruise at a low RPM, but you have to downshift if you're going to be going uphill or pulling anything...ESPECIALLY with oversized tires...

 

[beretzs]

Nick, my truck is right about 2700RPMs or so, about 200 or so more than crusing on flat ground. It is a little less with the propane on, since I am making a little mroe power. There is also the 73N and South, it has some huge hills that will slow the trucks down, but once you get your fuel where it needs to be and exhaust and intake are flowing well, and you hammer down, the hills will seem like a piece of cake. Cruising is fine at 2K and below, but if you wanna get up over the hills in ONE day, you are going to have to pump the fuel to her. I love to drive hills now the truck is tuned up. Makes it seem like I had two different trucks. Turn your fuel up, live by your pyro, and you will be happy. 3000rpms should not be scary. When I had 4.56's with no OD, I was constantly pushing and driving 3000K RPMS in order to drive 70 or so. Not going to hurt a thing, as long as your truck is in good shape and is cared for. It is not beating on it, just using all available HP.. They put governors on them for a reason.. If you are scared to run yours like that, come on down and you can whoop mine up and see that it will not hurt it. These engines are very well built, the more I drive it, the more I see it. With a turbo and propane, you should really be happy, hey, did I mention, turn the fuel up? Scotty

 

[Nickbf2504x4]

Just took her for a little spin...all i have to say is that i have been enlightened i know the next time i check my mileage it will be hurting but boy was that fun! I just ran a pretty flat stretch right by the house, but it's like i have a new truck! getting on the freeway here there is two lanes that merge into one i eased onto the ramp and a couple kids in a v-6 mustang squeled the tires around the corner and moved up beside me in the carpool lane...perfect test i thought left her in 2nd. til she hit 3,000 and turned on the 'pane! Now before i get shot down its obvious these kids weren't goin full bore, BUT like a ninja warrior i threw down a smoke bomb and dissapeared WOW i saw up to 8 lbs of boost before shifting to 5th...but I would be very recklessly driving by the time i reached 3,000 in 5th with my gearing its probably 90-95

The cliche should be : Leave them in the SMOKE

 

[beretzs]

Ah hah, you have found the light, sweet!!! That is what they are supposed to do, turn up the fuel and really put the power down, it is just a little, insy, winsy, bitty, turn, CRANK IT UP...... Scotty

 

[F350camper]

Good deal Nick, I was reading your boost numbers and they seemed really low. Glad to hear you found some more revs in your power band.