So who has bumped the power on a 6CTA cummins

[mike_belben]

i agree the steel line is a source of trouble. i replaced mine with straight NPT to compression fittings (not 90*elbows which must be clocked) and 1/8 copper tube with brass compression ferrules. i left extra length for vibration and my DT466 came to life. leaky AFC signal line was killing my off idle fueling and making truck undriveable when towing.

 

[duty calls]

great info, thanks

 

[Big Tex]

ANY IDEAS---On adding HP?
I am looking to do the same thing... I am not trying to race or destroy things on my M923A2 5 ton 6x6, but I do want more HP so when driving from my house to where ever I can go faster than 40/45mph. Also when I take it mudding I will have the low range gears for plugging along, but if I need some HP I'll have it.

 

[Jason O]

Big Tex -

If your motor is running properly, with correct fuel delivery, the pump adjustments listed in this thread will make a big improvement.


My 923A2 has the full rack travel turned all the way out, and a few turns of pre-boost fuel added as well. The truck moves pretty well, and not at all under-powered.

 

[74M35A2]

ANY IDEAS---On adding HP?
I am looking to do the same thing... I am not trying to race or destroy things on my M923A2 5 ton 6x6, but I do want more HP so when driving from my house to where ever I can go faster than 40/45mph. Also when I take it mudding I will have the low range gears for plugging along, but if I need some HP I'll have it.

Your truck has something wrong if you can only get 40/45mph out of a 923A2. My 925A2 (same engine) hits 67mph consistently up against the engine governor (2150rpm or so) on flat level ground, and my engine and fuel system are totally untouched stock (as far as I believe). That would be a different thread than this one, but you should make sure you have full air and fuel delivery to your engine (new filters, no collapsed fuel lines, etc...) before you start modifying, as the mods won't reap any benefits until you have at least factory performance levels, and then go from there. Think about checking fuel pressure at the top port of the engine mounted mechanical lift pump. There is a pipe plug located there which you could do so with, looks to be 1/8" NPT. Check pressure at idle and full throttle while loaded. Also look for exhaust smoke indicative of something wrong (sticking injector, etc...). I can even hold 60mph on extended freeway up-hills. Also make sure your tires are aired up to snuff. CTIS should do this if it is working, and if not, check and inflate all to spec. This also can make a significant difference. Could also check turbo boost level and boost reference into the pump as just mentioned above. As the turbo spins up and you hear it, the truck should pull significantly harder as fuel is added. If you don't sense this happening, something could be wrong, and it could be a simple fix.

 

[VPed]

Another simple thing to check is the base gasket where the turbo sits on the exhaust manifold. The two inboard nuts were loose on my truck (probably because they are a bit of a bear to get at). My gasket was in good shape so I tightened it back up and found it made quite a difference. A new gasket does not cost much and I understand this is pretty common.

 

[Big Tex]

On my M923A2 the guys in the field placed red tape over the speedometer at the 45/50 mph and over area... why? I don't know... but also the face plate from factory shows don't go over 63mph in BEST conditions, then 50mph and so on... whats with the red tape?

 

[Jeepsinker]

Turbo flange gasket on my 936 is blown out too. Apparently it got loose and I didn't catch it in time. Of course nobody can look up a simple gasket without an engine serial number.... Morons...

 

[roalcoal]

I thought mine was leaking also ! Ordered all new exhaust gaskets for the exhaust manifold and turbo flange when I pulled the turbo I noticed oil on the compressor wheel so I had to rebuild the turbo.Not sure where it was leaking from but all new gaskets and 1 broken exhaust bolt later it's back together and no soot on side of valve cover

 

[TurboMustang370]

I thought mine was leaking also ! Ordered all new exhaust gaskets for the exhaust manifold and turbo flange when I pulled the turbo I noticed oil on the compressor wheel so I had to rebuild the turbo.Not sure where it was leaking from but all new gaskets and 1 broken exhaust bolt later it's back together and no soot on side of valve cover

Did you buy a turbo rebuild kit or did you just strip it down and buy individual parts?

 

[roalcoal]

I got a rebuild kit

 

[TurboMustang370]

I got a rebuild kit

Do you have a part number and location you purchased it? thank you

 

[roalcoal]

Do you have a part number and location you purchased it? thank you

Not sure of a part number I got it off eBay , the company name is turbo lab America . Not sure if you have the same turbo but I googled H1E rebuild kit

 

[Big Tex]

To All - I have read the TM and and I am looking to see what standard tires are on my M923A2? I have seen many people change the tires and bob their deuce... but other than this and turning up the fuel rate are there any tips to get more HP? I take my deuce mudding and low and slow works 90% of the time... but that other 10% I am looking to get some HP to help push or more so CHARGE threw some deep holes.

 

[74M35A2]

To All - I have read the TM and and I am looking to see what standard tires are on my M923A2? I have seen many people change the tires and bob their deuce... but other than this and turning up the fuel rate are there any tips to get more HP? I take my deuce mudding and low and slow works 90% of the time... but that other 10% I am looking to get some HP to help push or more so CHARGE threw some deep holes.

Maybe I think you are mistakenly calling your 923A2 a Deuce?

The answer to your question is in the pages of this thread. Grab your favorite drink and go at it. Let us know if you have further questions after doing so.

 

[Big Tex]

OK,

Well thank you for correcting the "Nick Name" I used, your correct its a 5tone, not a 2tone. that being said See the pic of my Deuce? That is the nick name people use, but in reality you are correct about the small difference in the technical aspect of the wording I used. I have red that others have changed the fuel and turned up the fuel rate and adjusted tire pressure based on what surface they are driving on. My original question of increasing HP was base on people reading that I understand turning up the fuel rate and adjusting the tire pressure. But was there anything else. And I always have a good drink when tinkering / working on my Deuce / 5ton M923A2.

Thank you for your time anyway.

 

[Tornadogt]

OK,

Well thank you for correcting the "Nick Name" I used, your correct its a 5tone, not a 2tone. that being said See the pic of my Deuce? That is the nick name people use, but in reality you are correct about the small difference in the technical aspect of the wording I used. I have red that others have changed the fuel and turned up the fuel rate and adjusted tire pressure based on what surface they are driving on. My original question of increasing HP was base on people reading that I understand turning up the fuel rate and adjusting the tire pressure. But was there anything else. And I always have a good drink when tinkering / working on my Deuce / 5ton M923A2.

Thank you for your time anyway.

Lets start off with Welcome to the Website and Texas.


So your question, Upgrades above turning up fuel include Larger Turbo, Larger Injectors, modified intake tubing(air cleaners), exhaust upgrades (Straight Pipes) and larger tubing, Inner cooler,after cooler upgrades (anything to cool the higher volume of air coming into the engine from the upgrades). Most have been covered in this thread but we are always open to a discussion on these matters and new ideas. Along with these upgrades EGT Sensor and Boost gauge are required to monitor your progress as you modify your power.

 

[74M35A2]

OK,

Well thank you for correcting the "Nick Name" I used, your correct its a 5tone, not a 2tone. that being said See the pic of my Deuce? That is the nick name people use, but in reality you are correct about the small difference in the technical aspect of the wording I used. I have red that others have changed the fuel and turned up the fuel rate and adjusted tire pressure based on what surface they are driving on. My original question of increasing HP was base on people reading that I understand turning up the fuel rate and adjusting the tire pressure. But was there anything else. And I always have a good drink when tinkering / working on my Deuce / 5ton M923A2.

Thank you for your time anyway.

If you still want more after you have turned the fuel up, I'd suggest installing a used Cummins ISX 15L. It would be a lower cost and more reliable path to 500hp once you have the 6CTA8.3 at the 300hp mark. Additional power increases beyond fuel rate increasing is best found on tractor pulling websites.

 

[Big Tex]

Thank you. Good Tips.

 

[74M35A2]

You could also consider other higher hp engines besides the ISX, such as a Detroit 8V92, Series 60, or Cummins 400hp 855. They can be had for a more reasonable cost, but they are all heavyweights that add a lot of mass over an 8.3L.