more power--better MPG ?

[allan5oh]

I'd love to get that guy from pittsburgh power on here, maybe he could teach us all some things. Most things I've read from him I agree with, some things not.

[allan5oh]

What I would really appreciate is someone dynoing some trucks and comparing the BSFC numbers pre and post modifications. Also, just to see what kind of #'s the OEM engines put out, bone stock.

[PackRatTDI]

I did NOT increase the rating of the transmission or clutch and ran it fine for years with no driveline failure (until it was stolen).

The key to that is being gentle on the throttle. Pittsburg Power has boosted engines to 700+ hp with torque to match running through ancient RTO-12513 transmissions without problems because the drivers understand the need to be gentle when taking off. Drive it like a rookie from trucking school and you'll wind up with a transmission case full of gear shards.

[Teal 95 KW]

Have those of you that are stating that you "don't buy into this" actually tried it?? Or are you just stating your opinions??

I'm all for the Pittsburgh Power stuff...just stated that I see no need to have it on my truck currently b/c of the power I'm already making...no need to get myself into more trouble

I did NOT increase the rating of the transmission or clutch and ran it fine for years with no driveline failure (until it was stolen).

Someone stole your driveline? That's some ****! :P

[allan5oh]

I'd definitely agree with the easy on the take-off. Even stock motors can grenade a clutch/driveshaft pretty quick! A 13 speed has about 12:1 ratio, that means the driveshaft is seeing 12X the torque that the engine is producing.

[Truckdobe]

Actually someone stole the whole thing; truck, trailer, tools, personal stuff, EVERYthing. :evil: :x

I thought the original topic was HP and increased fuel mileage... that's what I was responding to. I increased HP; changed the turbo, injectors, timing, pump settings and a few other minor things and got a significant increase in mpg. Avg mpg after HP increase 6.2-6.4 w/heavy idle time, @ or slightly above gross most of the time; before it got 5.4-5.7.

The driveline was 1450 ft lbs; 15 spd & clutch. Being easy on the driveline is also easier on fuel. Since there are only 2 of us driving and our styles are similar we don't really worry about driveline problems, we haven't had issues with any of our trucks regardless of "improvements" that have been made.

[btinc]

And, FWIW-As much as I would like to have more power, I have more than I need right now (can pull the Grapevine at 60mph grossed out) I don't understand spending $7k for the turbo, box, and exhaust when they even state the most drivers who have the set-up only run on the 2nd or 3rd setting of 7....that's an extra 75hp? No reason to spend all that money on the set-up when you have speed limits, and pushing the truck (at the 60mph I pull the grapevine at, my mpg on my dash display drops to about 3.8-ish) like that, you lose fuel mileage BIG TIME. I guess aside from bragging rights, it doesn't do a whole lot in the real world...other than get you in trouble.

Wow 7k for the set up might be a little much, but hey you could be right, just to clarify, my turbo and exhaust did not come from the diesel injection it was a set up that i have run for years and was compatible with the box. My fuel mileage for a year and half is up a tenth and half. Running the 11 western the box makes for even more enjoyable mountain driving.

[allan5oh]

I thought the original topic was HP and increased fuel mileage... that's what I was responding to. I increased HP; changed the turbo, injectors, timing, pump settings and a few other minor things and got a significant increase in mpg.

The conversation did change for a bit. Having more HP does not automatically mean better fuel mileage, but what of those laundry list of things actually increased fuel mileage? If they were all done at the same time, you'll never know. Could've even been old tired injectors.

[special k]

If a truck that uses 15lbs of boost just to maintain road speed doesn't reduce fuel mileage while on the box. I could definitely see some improvement in a truck that only uses 5lbs. All the box does is take away some of the lag in the fuel system. Thats why my cruise works better and we had to make the cruise less aggressive. I wish we could back it off more. Do you think they give some leeway in the turbo sizing? A lot of horsepower rating will use the same size turbo. They will tell you if you run the top setting you're not getting all the power you could with the stock turbo. To me that would explain why it only puffs black smoke in the top settings. The turbo isn't supplying enough air and the mixture becomes rich. Fuel mileage is mostly in your right foot,

[jimmyg]

I'm back
Thanks for all the replies..it does help to have different opinions ! I believe that no matter what you have in your truck the biggest effect is how it is driven. I've been an O/O for twelve years ( thats no record) ,fourth truck and fifth engine I am in this buisness to make money so I am inherintly easy on the fuel pedal , but it would be nicer to just kick back a little and glide up some of the hills that I am downshifting to get over ! Even empty , with the open top walking floor the engine consumes more fuel than other trailers that weigh the same. I believe that I will gamble on the box.....I'll get back to ya and let you know what happen's

[pepe4158]

Wouldn't doing something like that void a warranty or decrease the life or the engine? I

My quess off hand is defintly deecrease the life, but my mechanical experience comes from a couple years as a car mechanic many years ago and I know almost nothing about Semis and diesels, except for a few common points.....for example I did suspension work and new when I bought my first 3 axel to climb under and look for rotting rubbler and bad fittings.

You know I remeber in the car buiz too you always saw after-market retro-fits that by-passed this or made this better, and every good mechanic I knew that I was learning from always frowned on them as a bad idea, an engine is engineered a certain way to run, by bypassing it you are basicly declaring you are a better automotive engineer then he was

[pepe4158]

Wouldn't doing something like that void a warranty or decrease the life or the engine? I

My quess off hand is defintly deecrease the life, but my mechanical experience comes from a couple years as a car mechanic many years ago and I know almost nothing about Semis and diesels, except for a few common points.....for example I did suspension work and knew when I bought my first 3 axel to climb under and look for rotting rubbler and bad fittings.

You know I remeber in the car buiz too you always saw after-market retro-fits that by-passed this or made this better, and every good mechanic I knew that I was learning from always frowned on them as a bad idea, an engine is engineered a certain way to run, by bypassing it you are basicly declaring you are a better automotive engineer then he was