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This may or may not be going anywhere but I'm kicking some things around here. I'm wanting to know if anybody has a 285 hp Maxidyne that they've done any tweeks on or made improvements to it for more power. Like most factory engines it seems like they're not at their full potential until something is tweeked a little or something else added to it to improve the power or just efficiency of the engine. I'm planning on tearing down my 75' ENDT676 to re-seal and gasket the thing before putting it back in the chassis eventually. Course I'll check the tolerences and all while I have it tore down but was wondering if while I have it to that point, are there any suggestions I could do to optimize its performance. I'm sure someone on here has been in my shoes and has tried it before, just thinking out loud. I'm not looking for a race motor here, just to improve on what I have, if that's possible...Open to all suggestions

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This may or may not be going anywhere but I'm kicking some things around here. I'm wanting to know if anybody has a 285 hp Maxidyne that they've done any tweeks on or made improvements to it for more power. Like most factory engines it seems like they're not at their full potential until something is tweeked a little or something else added to it to improve the power or just efficiency of the engine. I'm planning on tearing down my 75' ENDT676 to re-seal and gasket the thing before putting it back in the chassis eventually. Course I'll check the tolerences and all while I have it tore down but was wondering if while I have it to that point, are there any suggestions I could do to optimize its performance. I'm sure someone on here has been in my shoes and has tried it before, just thinking out loud. I'm not looking for a race motor here, just to improve on what I have, if that's possible...Open to all suggestions

Hi Tony, the way you plan to use that truck really will not tax, (how bout that term for a guy in California) that motor at all. I would however pull the pump and injectors, send them to a fuel shop to be checked/calibrated and bump the pump output up about 15% over stock. You really don't need to go anymore as it's output will never be realized to full potential. That motor already has more power than you will ever need.

I would also send the air induction parts into various shops to ensure they are perfect prior to putting them into service. Lots easier to work on engines when they are on the floor rather than in a chassis.

Might as well put a set of bearings in it too while it's easy.

Rob

Dog.jpg.487f03da076af0150d2376dbd16843ed.jpgPlodding along with no job nor practical application for my existence, but still trying to fix what's broke.

 

 

bump the injection pump settings up 15-20% install a front mount if you have the room. if no room tweak the tip turbine boost inlet valve a little to allow more boosted air flow into the turbine. make sure the puff limiter is working correctly or disable it..you should feel a increase with this advice.

Trent :SMOKIE-LFT:

Hi tony,i'm right with rob on this subject, pump and injectors is the way to go as far as im concerned especially for your purpose/use .Will help realize maximum horsepower and overall performance as well. I can only assume that being in calli that you are probably required to run a muffler as opposed to a straight stack? Despite the noise, maxidynes seem to run somewhat better (in my expeience) with the reduced backpressure of not having a muffler. Do you have a good diesel injection service available to you? pump/injector work can be pricey!.......mark

Mack Truck literate. Computer illiterate.

Thanks for all of the tips. Crazy how just a few little tweeks can really make a difference. Thanks for the poke in the ribs Rob, you ain't a kidding out here with the stinkin' taxes. Was just informed a few months ago when I got my taxes done that my overtime pay is no longer taxed at 36%, now it's 52%, glad to see the govt. is getting more of it than I am. Guess I'll just have to spend more time away from work and more on my truck. I spoke with the guy in Wisconsin that you recommended for the pump and injector service, told me to just box it up complete and ship it out whenever, seemed like a real nice guy. I'm hoping to send it off this fall as my goal is to have the chassis completely re-done by spring so I can set the cab on and take it for a spin. I'm not the most patient person and not hearing what that engine sounds like is killing me. Mark as far as straight pipes go they're a no no out here but I don't think I would get hassled :) I don't like too loud of an exhaust though, especially if my boy's gonna be ridin' with me cause his hearing is really sensitive due to his being blind. He likes some noise but tends to hold his hands over his ears if it's too loud.

Thanks for all of the tips. Crazy how just a few little tweeks can really make a difference. Thanks for the poke in the ribs Rob, you ain't a kidding out here with the stinkin' taxes. Was just informed a few months ago when I got my taxes done that my overtime pay is no longer taxed at 36%, now it's 52%, glad to see the govt. is getting more of it than I am. Guess I'll just have to spend more time away from work and more on my truck. I spoke with the guy in Wisconsin that you recommended for the pump and injector service, told me to just box it up complete and ship it out whenever, seemed like a real nice guy. I'm hoping to send it off this fall as my goal is to have the chassis completely re-done by spring so I can set the cab on and take it for a spin. I'm not the most patient person and not hearing what that engine sounds like is killing me. Mark as far as straight pipes go they're a no no out here but I don't think I would get hassled :) I don't like too loud of an exhaust though, especially if my boy's gonna be ridin' with me cause his hearing is really sensitive due to his being blind. He likes some noise but tends to hold his hands over his ears if it's too loud.

You'll like Fred's work. If you give him the criteria you wish to operate within, that injection system will meet it without a doubt.

Thought you'd get a "kick" out of the tax comment!!

Rob

Dog.jpg.487f03da076af0150d2376dbd16843ed.jpgPlodding along with no job nor practical application for my existence, but still trying to fix what's broke.

 

 

Thanks for all of the tips. Crazy how just a few little tweeks can really make a difference. Thanks for the poke in the ribs Rob, you ain't a kidding out here with the stinkin' taxes. Was just informed a few months ago when I got my taxes done that my overtime pay is no longer taxed at 36%, now it's 52%, glad to see the govt. is getting more of it than I am. Guess I'll just have to spend more time away from work and more on my truck. I spoke with the guy in Wisconsin that you recommended for the pump and injector service, told me to just box it up complete and ship it out whenever, seemed like a real nice guy. I'm hoping to send it off this fall as my goal is to have the chassis completely re-done by spring so I can set the cab on and take it for a spin. I'm not the most patient person and not hearing what that engine sounds like is killing me. Mark as far as straight pipes go they're a no no out here but I don't think I would get hassled :) I don't like too loud of an exhaust though, especially if my boy's gonna be ridin' with me cause his hearing is really sensitive due to his being blind. He likes some noise but tends to hold his hands over his ears if it's too loud.

Hi tony,thats one of the reasons i mentioned that,injector/pump work is the way to go! would be REALLY loud without a muffler no doubt! i think you are on the right track for what you're after horsepower/performance wise,besides performance mufflers can be had for big trucks too! i forgot to mention that in my response earlier.....mark

Mack Truck literate. Computer illiterate.

Wot we do for a bit of qik gas pedal response plus black smoke

is put a washer under the puff limiter

it tends to over fuel on take off = bit more get up n go

all is needed iz a 2 cent washer ( or haz the price of them increased L8ly

LOL

OK 10 cent washer then

cya

§wishy

Tony...

I have ran that engine in the old R-600 and it was pretty strong then, I would also recommend that you pull the heads and give it a valve job. I think the engine is in good shape it didn't use oil. You cant go wrong with the injector work, but I think you would have more power than you could get to the ground in stock form, might save some money in fuel,and rear tires!!

Fred

15 gears...no waiting!

This may or may not be going anywhere but I'm kicking some things around here. I'm wanting to know if anybody has a 285 hp Maxidyne that they've done any tweeks on or made improvements to it for more power. Like most factory engines it seems like they're not at their full potential until something is tweeked a little or something else added to it to improve the power or just efficiency of the engine. I'm planning on tearing down my 75' ENDT676 to re-seal and gasket the thing before putting it back in the chassis eventually. Course I'll check the tolerences and all while I have it tore down but was wondering if while I have it to that point, are there any suggestions I could do to optimize its performance. I'm sure someone on here has been in my shoes and has tried it before, just thinking out loud. I'm not looking for a race motor here, just to improve on what I have, if that's possible...Open to all suggestions

You could get a robert bosch pump from a 300 plus(315hp) if you have a 10-13 speed, if you have a 5-6 speed might get the exaust temp too high at low rpm. Ron

Hi Tony, as Rob and all have said, The first thing is to give it more fuel but if you want to go a different way you can get more boost by upgrading the existing turbo to the 350 turbo, or by machining out the original compressor housing in the turbo and fitting the larger compressor wheel.I have done this in the past and at the same time I made up a short funnel shaped adapter to take the 4 inch outlet on the turbo out to 5 inches so that there is a 5 inch pipe right to within an inch of the turbo. This makes a big difference to the acceleration as the turbo spins up quicker. I also put lagging on the exhaust from the turbo back and fitted the 5 inch muffler to keep the noise down. With this system it goes better then the original straight through system without the muffler. Either way you must keep a close eye on the Pyrometer on the long hard pulls. The other thing is - do you have the big air cleaners fitted? The original cleaners restricted the air to the turbo and shortened the turbo service life. An air ram on the top of the air cleaners also helps with the boost, especially at higher speeds. Best regards - Michael

if anybody has a 285 hp Maxidyne that they've done any tweeks on or made improvements to it for more power.

Ok Tony, now I see you want to win the "slow truck" H drag race because "first to street" award in the H series show down is in jeopardy given my potential outsourcing plan :D

Just remember, however, when you are trying to grab about 10 double clutch shifts in this thing to get out of the hole worrying you might grenade the tranny, I might just be pressing the accelerator and letting the magic of Allison run right past you regardless of how many horses you squeeze under your cab!

Sure, I am a wimp thinking about an Allison (this is for the general board audience - Tony supports the 'the title is in your name - do what you want plan'), but I will be a wimp with a smile during the "slow truck" H drag race I bet.

Actually, just disconnecting the air line from the puff limiter cylinder will make a night & day difference in throttle response & costs nothing.

It will create black smoke on acceleration though, I suppose maybe that won't fly in CA.

.

"If You Can't Shift It Smoothly, You Shouldn't Be Driving It"

Tony, If it's an American Bosch Pump On your truck I could tell you how to turn some juice to it real easy (if you want to save a couple a bucks on pullin the pump) I've done it many times on my old EM6-300's & E6-350's with the ambac pump

The 300 (285hp) engine does have plenty of power as is. I pulled loads of kyanite and steel weighing over 50,000 lbs. regularly with one,through the mountains of Va, W.V, and western Pa. Turning the pump up is easy and a little more fuel makes a lot of difference and won't hurt anything. I knew some guys that got a little carried away turning them up though, thinking if a little is good a lot must be better...not always true!

Producer of poorly photo-chopped pictures since 1999.

The 300 (285hp) engine does have plenty of power as is. I pulled loads of kyanite and steel weighing over 50,000 lbs. regularly with one,through the mountains of Va, W.V, and western Pa. Turning the pump up is easy and a little more fuel makes a lot of difference and won't hurt anything. I knew some guys that got a little carried away turning them up though, thinking if a little is good a lot must be better...not always true!

Yup, I've pulled a couple with melted pistons from too much fuel. That is one of the reasons I only suggest 15% fuel delivery rate over factory. The second factor is that most pump shops will not warrant their work if the pump output is raised 20%.

A stock 285 tuned correctly will slip the tires in a single axle tractor with a light trailer attached without much effort. Increasing the power by much is of relatively little gain in the prospected usage.

At a couple hundred bucks a hole to get a pump rebuilt, I prefer to have a guarantee the thing is correct for a respectable amount of time in usage.

Rob

Dog.jpg.487f03da076af0150d2376dbd16843ed.jpgPlodding along with no job nor practical application for my existence, but still trying to fix what's broke.

 

 

Mornin' Rob.

What pump shop in WI did you suggest to him? Valley Diesel in Neenah?

.

Mornin Herb, I don't really know his business name but the gent I've dealt with is Fred Kevlek. I've always talked to him solely.

Rob

Dog.jpg.487f03da076af0150d2376dbd16843ed.jpgPlodding along with no job nor practical application for my existence, but still trying to fix what's broke.

 

 

here is our 285 powered sled puller. only thing done was the pump was turned up and puff disconnected. 40,000lbs and wheels spinning. 2nd direct. these motors can do some impressive stuff with just stock parts....

http://www.youtube.com/watch?v=ESgdON55V6E&feature=related

http://www.youtube.com/watch?v=zKvW12yLMWU

Trent, are you guys running that at the Mackville Nationals this year?

Even if you're not, then you oughtta swing up this way & attend this show:

http://www.mackvillenationals.com/

The company I work for is a major sponsor of the pulls, and this year, instead of crushing cars with a monster truck, my boss is gonna take the D8N Cat dozer out on the track & demolish the cars!

.

"If You Can't Shift It Smoothly, You Shouldn't Be Driving It"

Will have to see. I have the RS700 all torn apart waiting for parts. If its not ready I would have no way to get the sled pulling tractor up north. I will let you know if we plan to go. sound slike a good time..

Trent

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