Detroit 8.2T Turbo Diesel Blue Bird School Bus

SKIBUSENTRPNR · 09-29-2008, 05:50 PM

Hello Everyone,

New potentional owner of the above. What would you recommend for performance upgrades and possibly a transfer to vegetable oil? I am going to convert it into a ski bus, so any ideas!? Thank you for oyur time and any input that you might have.

kl

nevrenufhp · 09-29-2008, 09:17 PM

The 8.2 isnt a performance engine by any means. It was made for good fuel economy, hence the name "Fuel Pincher". It'll run on bio just fine, but keep up on routine maintenance, and you'll be fine. Try to add power, and it'll pop a head gasket or crack a head. Even stock, they are prone to this.

SKIBUSENTRPNR · 09-29-2008, 09:34 PM

how do you recommend i run it off bio diesel then and also would a new intake/filter be too much? along with a new turbo? any idea on the mileage? thank you for your time

kl

nevrenufhp · 09-29-2008, 09:47 PM

I never really looked in to bio, so I cant really say what to do to convert. A good flowing intake setup wont hurt it a bit. A new turbo likely wont do much of anything except lighten your wallet. The 8.2 we have at work gets around 12-13mpg last I remember, but it's a utility truck that's topped out at 65mph.

the_experience03 · 09-29-2008, 09:49 PM

Bio and WVO are two totally different fuels. I wouldn't run either if you're going to be using this thing as a ski bus. The risks are just too great. Both fuels have a much higher gelling point than dino diesel and could potentially leave you stranded on the side of the highway. During the Spring, Summer, and Fall this is but a minor convenience. During the winter it could be deadly. AFAIK none of the children ferrying buses in this neck of the woods run more than the mandated amount of bio.

SKIBUSENTRPNR · 09-29-2008, 11:31 PM

AFALK? sorry i do not the difference between the two fuels. i do however understand how they could gel up in the winter, even with the mandated amount? im not looking to get speed out of this thing but at least to be fine on the freeway and going to the mountains and back and better mph if an intake helps. do you have any that you would recommend? also is it possible without sacfricing performance, adding "stacks" for an exhaust system?

thank you very much for your time

kl

paul iossi · 09-30-2008, 12:27 AM

I wouldn't take a chance on alternate fuels in the winter months. Your bigest bang for the buck is going to be a low restriction exhaust system, the air has to get out if you want more to get in, then look at a high flow air filter assembly, after that pump adjustments for fuel and timing.

SKIBUSENTRPNR · 09-30-2008, 02:04 AM

So wouldn't stacks be the way to go then as they offer a lot of air to escape? and i would put them on either side, right in front of where the doors are. also thank you on the pump information. but what do you mean by a high flow filtration system? is that expensive or is it just a filter?

thank you very much for your time

kl

the_experience03 · 09-30-2008, 07:12 AM

AFAIK=as far as I know

WVO/SVO=waste veggie oil or straight veggie oil. This fuel in unrefined. The nasties are filtered out and the water is usually allowed to separate, but that's it. Most, but not all, systems running this fuel will require two tanks, one for diesel and the other for the veggie oil. The vehicle is started on diesel and allowed to warm up while also warming up the veggie oil via coolant heat exchangers. Heating up the oil thins it out to the point that it is injectable. A series of valves are switched and the engine is then allowed to run on the heated veggie oil until shut down when the valves are then switched back and the engine allowed to run long enough to clear the lines of veggie oil.

Biodiesel=waste veggie oil that has been refined, usually through titration with methanol and lye. The end result is a fuel that is usable as is without the need for a second tank or heating. Various states have different mandates for differing amounts of bio to be added to dino diesel resulting in B5 (5% bio) on up to B100 (100% bio). Engine manufacturers certify their engines for a certain percentage.

In either case the risk of gelling is greater for both as I stated before. I know my engine is particularly cold blooded. If I used my veggie heat exchanger during the winter there might not be ANY heat left over for the cabin. As it is it won't make enough heat at idle to keep the thing warm during the winter.

SKIBUSENTRPNR · 10-01-2008, 02:37 PM

Hey, my engine wont start either. i guess he charges the batteries and it turned over but then nothing. i am taking a kenworth mechanic with me to look at it and hope it is all well. any advice. stacks?

thank you very much for your time

kl

paul iossi · 10-02-2008, 12:09 AM

you have to have enough battery voltage to keep the engine controller turned on while cranking, at some point around 10V the ECU will switch off and you don't have any control of the injectors. = no start condition,
The new electronic engines are user friendly and super efficient until you have a problem, then their is nothing like good old fashioned mechanical injection.

nevrenufhp · 10-02-2008, 08:01 AM

For the most part, the 8.2 needs a lot of cranking to start anyway. Go for the stax!

paul iossi · 10-02-2008, 10:35 AM

stacks or 4+ inch out the back with mandrel bends and no muffler

paul iossi · 10-03-2008, 04:24 PM

mechanical injection pumps need a lift pump to supply them with fuel, they pressurize the fuel to high pressure and distribute it to the injectors, they do not have a provision to transfer or lift fuel from the tank and thru the filters to the high pressure pump.

the_experience03 · 10-03-2008, 09:33 PM

The 8.2 uses unit injectors that act both as the injector and the high pressure pump, much like the older 2 stroke Detroits. This is what makes it advantageous in theory. In reality I don't think I've seen nearly as many 8.2 WVO conversions as I have seen of those running the Bosch MW or P series inline pumps.

SKIBUSENTRPNR · 10-05-2008, 02:27 AM

So i bought the bus and it wont start but we think that with some new batteries that it should be alright. also what does everyone think about train horns, stacks, air filters/systems, and other accessories and new alternators? thanks for your time.

kl

SKIBUSENTRPNR · 10-05-2008, 02:31 AM

so the gent i bought the bus from lives on top of a mountain and you should see the dirt road up to his house, its crazy and has hairpins so it must do just fine on hills and i have abondoned the veggie bus idea because this thing is for winter use. to the person who posted this

"stacks or 4+ inch out the back with mandrel bends and no muffler" would you mind pming me. this sounds very interesting but i dont know what it means. what about stacks right behind the engine? and i was thinking no muffler but what about the mandrel bends?

thanks everyone for their time

kl

SKIBUSENTRPNR · 10-05-2008, 02:35 AM

does biodeisel do okay in the cold winters?

thank you for your time

kl

paul iossi · 10-05-2008, 08:07 AM

mandrel bends = full diameter, not crimped or restricted like most exhaust systems. your aftermarket big truck parts supplier can get 90% mandrel bends, 10 ft sticks of straight pipe and turbo flanges, it then becomes an exercise in cut,fit and weld a low restriction exhaust system. take your time, getting from the turbo to under the bus and paralell with the frame is time consuming after that your home free. straight back over the axle and under the rear bumper.
your other option would be to use the stock turbo down pipe and then fab an adapter cone up to your chosen exhaust size.

lapeer20m · 10-05-2008, 08:42 AM

the exhaust doesn't need to exit the rear of the bus. it's just some silly rule put in place to keep children who ride the bus from sucking in diesel fumes. 30 feet of exhaust pipe is not needed on a skoolie conversion. You could exit in stacks right behind the motor, or onto the ground kind of pointing to the side anywhere under teh bus.

Buses tend to have 4" exhaust. I don't think this is the restriction in the system. It's the puny low hp motors that make buses slow, not the engines ability to breath.

You may also like: