more power from your diesel engine

[the_experience03]

Hey thanks, Jason! Your pump looks nearly identical to mine (as it should) though I'm unable to verify that that is exactly how mine is laid out since the bus is 60 miles from here right now, but I will give it a look this weekend.

Can you explain what to expect out of each screw? Does the smoke one also control the idle speed?

[lapeer20m]

Turning up the fuel delivery rate does not affect idle speed, it will however make black smoke come out your exhaust when you step on the throttle until the turbo spools up. You can move the "star wheel" Turning it one way makes more smoke, the other direction causes less smoke. Many people apparently don't mess with the wheel at all and just let the engine smoke a bit on takeoff. To fix the smoke problem, you have to remove the smaller plug and turn the "star wheel" This effects how much diesel fuel is pumped into the cylinders before your turbo spools and boost pressure is created.

here is another good link that describes how to turn up the fuel delivery rate


http://www.thedieselgarage.com/forum...6958#post66958

Tightening your govenor springs will cause the rpm to increase. This mod is desirable because it also increases the engines max rpm. My engine is rated for 3100 rpm, but was governed @ 2,400. I turned it up to about 2,700. After you tighten your springs, you will have to back off the idle speed screw. This is the screw that is connected to the throttle linkage and is diffeent on just about every vehicle.

here's a good link for the gov springs....it's a tutorial on how to install new springs, but if you simply tighten your current springs about 2-3 clicks it'll increase your rpm's. The tutorial is for a cummins 5.9, but the same pump is on the DT series and the ford 6.6/7.8 litre.

http://www.flex.net/~triplem/new/govspring.htm

while i'm at it, here is a link to a newer style 466/360/5.9 pump. Instead of installing the "new" fuel plate, you can grind down your old one...if you really wanna do this let me know and i can find more data for ya, even though i have not actually done this.

http://www.tstproducts.com/INSRUCT98.pdf

[lapeer20m]

i have turned up the fuel delivery rate, and tightened the governor springs. I'm very pleased with both mods. I don't have a skoolie dyno, but i can feel in the seat of my pants significantly more accelleration with the increased fuel delivery rate.

I've driven 1K miles or so with the increased fuel rate and have had no problems as of yet. If i take the bus out west again i'll be curious to see how it's hill climbing ability has improved.

as far as fuel economy......i have not actually checked to see if the bus now gets fewer mpg, but one would assume that it does. I do keep the gas pedal @ ~3/4 throttle now to do the same speed i used to keep the pedal all the way to the floor. At speed on flat ground the bus might not use much more fuel, but as far as hillclimbing and accelleration i'm certian it'll use fuel at a faster rate.

[the_experience03]

Here;s a link with instructions for just about any diesel we might have in our buses. After reading the various methods, I sure am glad I have an inline Bosch pump.

http://www.geocities.com/kaufmanns@s...rformance.html

[lapeer20m]

Originally Posted by the_experience03

Here;s a link with instructions for just about any diesel we might have in our buses. After reading the various methods, I sure am glad I have an inline Bosch pump.

http://www.geocities.com/kaufmanns@s...rformance.html

that's the site i got my instructions from...very informative

[lapeer20m]

someone was looking for this link.....i finally found it!

just an update on the bus:

everything seems to be just fine after lots and lots of miles. I'm getting ready to take her out to nevada and back again on a 5K mile road trip.

[waywardfool]

found this the other day....with pics...

http://www.freewebs.com/nevrenufhp/index.htm

[lapeer20m]

i took her out west for another 5K mile roadtrip. My fuel economy was significantly higher this year than in any previous year. I don't remember what the final numbers were, but above 8 mpg. I had been averaging between 6 and 7 mpg in previous years. Hillclimbing was amazing compared to how she used to perform. The only problem i discovered is that the engine now makes more heat than the cooling system is able to dissipate while hill climbing. I never had to stop, but did have to let off the gas pedal a bit to keep things from getting too hot. Having an electric fan in conjunction with the stock fan might help solve this issue.

You might think that 2 mpg isn't a big deal, but it equates to several hundred dollars on a 5K mile roadtrip.

i definitely recommend turning up the fuel, and turning up the governor on one of these motors!

[Train-train]

Well, I have the 5.9 cummins and the '95' p-style pump. I am interested in getting a little more out of my engine. Just to clarify, you actually got better fuel mileage after turning your engine up? I think I already know the answer here, but I will ask just to see if I am wrong, Does turning up the Horse Power hurt anything if I convert it to veggie? I would not think that it would make any difference what fuel it is using, but please tell me if it does.

[lapeer20m]

I expected to get worse fuel economy, and i have no scientific way to explain it, but i actually got better fuel economy after i turned up the hp on my bus. This wasn't just a short term test, but a 5K mile roadtrip. I've done the same trip 3 times with the same bus...although year two i was loaded really heavy. I drove a total of about 30K miles with the bus, and the last 8 or 10 thousand was with the higher horsepower.

After i turned up the fuel, i went from driving with the pedal to the metal most of the time to having hte throttle at about 3/4 to maintain the same speed....about 60 mph for me.

[wmah]

What you say about more hp getting better fuel economy makes me think of something a owner of some buses in a nearby city.
This is a city where there are a few bus owners that operate for a school district.
The guy was telling me that most of them where ordering their buses with engine with higher hp even though it cost them more up front. and tis guy would also order highway gears so he could go faster. He also said the one guy would get the lower hp engine and he always had to cram his foot into the floor to keep up with the other guys on a charter trip and by doing so he had to fill up more often. So he learned eventually and started putting more money up front for more hp.
I would have bought a bus from they guy I was talking to but his were too new and I'm sure he sold them to the dealer for a good chunk of change when he got his new one. And they didn't have the lift door. I believe one of them was a TC but it wasn't his newer one which will do around 80mph.

[nevrenufhp]

Digging up this old thread, which should've been in the how-to section.
The link to the geocities site on the first page is the first one I did, then I moved it to freewebs so I could post pix with the articles.
And, another article, bumping up the timing:
http://www.thedieselgarage.com/forums/s ... php?t=6041
To explain the fuel usage a little better. It takes an engine a certain cc's to get to, say 210hp at 2500rpm. If you make more power at a lower rpm, you acually use a few less cc's of fuel. On a low power engine, the engine is winding up to max rpm and staying there longer before the next gear shifts. A big reason why a 500hp 15 liter truck engine can get 6 mpg. The biggest factors in a bus would be; hp level, timing, gearing(trans and rear end), and the fateful aerodynamics. I thought about making a new how-to article that had all this stuff in it, but I'll need to take more pix or a video to really bring it home.

[nevrenufhp]

I also made a few how-to videos. First the fuel rate, then the timing, and finally tightening the gov springs:

http://www.youtube.com/watch?v=C2pJZbYuVHs

http://www.youtube.com/watch?v=XRzQkiOP9rI

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

[kotflb]

I also made a few how-to videos. First the fuel rate, then the timing, and finally tightening the gov springs:

Thank you for for updates. I have a non after-cooled dt466, rated at 195hp. Whats the highest safe hp I can go by using these methods? I don't believe I have the room to install a after cooler. Also, what timing setting would I need for this. I'm looking for max power for hills and fuel economy for the flats. The transmission is a mt643. Thanks in advance.

[nevrenufhp]

Originally Posted by kotflb

Thank you for for updates. I have a non after-cooled dt466, rated at 195hp. Whats the highest safe hp I can go by using these methods? I don't believe I have the room to install a after cooler. Also, what timing setting would I need for this. I'm looking for max power for hills and fuel economy for the flats. The transmission is a mt643. Thanks in advance.

You can go pretty far on the fuel screw, I'd say a good 6 full turns. New timing depends on the original timing, and how much more power you add. Some engines are 22* from the factory. I'll speculate yours is around 13-15* now. For the stock to mild combo, start with 17*. Maxed out fuel screw and tighter gov springs can go to 20*.
The 93-97s timing numbers are 17 for most all mods, and 19 if you tightened up the gov springs, but driving it hard can pop a headgasket. Same figues go for the Fords(6.6 & 7..

[grampsbutler]

Does anyone know whether there is a the fuel pump can be turned up on the Detroit 8.2T?

I know that many of you hate the 8.2, but I am stuck with mine and would love to get a little bit more power out of it. Any ideas?


Graham
http://www.intrepidequipment.com Hauling handcycles in an an 83 Bluebird

[nevrenufhp]

No, the 8.2's dont have a fuel rate adjustment that an average Joe can do. They are done like the old 2 strokes. I suggest to be happy it runs good now.

[grampsbutler]

Thanks! I will work on trying to be satisfied with the 8.2L

Graham
http://www.intrepidequipment.com Intrepid Handcycles

[Jolly Roger]

I have an 8.2 and an at545 and can only do 49 mph.
The older men at the bus barn told me I could adjust the governor's to go faster but I would burn up the rear end and they day we got to pick the bus up I had to go to work and my wife had a friend to bring jolly roger home so I didn't get to ask what gear's to change to? I can't get any garage's around here to talk to me and the part's stores won't make suggestions? The interior is 90 % and the exterior is primed, holding tank's installed with only a few plumbing item's to finish and electrical is at an acceptable(working) point. I would just like to do more than 49? I used to be a mechanic and gave up on the computer mess. I have an 85 8.2 non turbo and don't know where to begin adjusting for more speed and I can't get anyone to tell me what gear's I need to change to in my eaton rear end ?
I have a garage that will do it but I have to bring the hog head to them not the whole rear end? If I have to do all of that in a gravel drive way I know enough to mesh the gear's myself. I can't get enough info about my set up to figure out what gears to buy?
8.2 with at545 and eaton rear model 16s

[Kubla]

first you need to know what rear end ratio you have already, and you might want to check and see if your tranny is even shifting into forth gear, 49 sounds like maxed out in third