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Mack AI 460 AI427 AMI low torque low horsepower poor fuel mileage granite , dead dog , remediation

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That would be great, I've been told 427 up is where it it takes iron over electronics

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19 hours ago, Bigjohn4300 said:

Yup that would be her! I like the ole gal, tough as nails, but when she is tagging the excavator, she is around 81k, could use a bit more umph, but when she is at 81, and not pulling, it's dangerous because it's unpredictable, you may pull out and be fine, or you may pull out with maybe 100 hp and that seat pucker factor comes into play

They make a AI-300A and a AI-375A just for use with the Allison trans you have . To go the the 375A you have to change to the bigger injectors and get you dealer to do the HP software download.  To go to 427 or 460 you will need both turbo and injectors and download. And Im not sure Mack will bump it up that high with the Allison trans. 

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Will the Allison handle the extra torque of a power upgrade? Generally the lowest rating of a Mack 6 cylinder engine was a derated version to stay within the torque limits of an Allison transmission.

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I know the newer Allison's can handle the 505 HP but unsure on the older ones. AI-300A has 1200 ft pound of torque and the AI-375A has 1350 ft pound torque. 

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There was usually a huge price gap between the top capacity Allison like the 4000 series and the next model down like the 3000 series, so the engine makers would often offer a low torque engine to match the lower priced Allison's capacity.

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10 hours ago, TeamsterGrrrl said:

There was usually a huge price gap between the top capacity Allison like the 4000 series and the next model down like the 3000 series, so the engine makers would often offer a low torque engine to match the lower priced Allison's capacity.

big difference in physical size too... B400/3000 series weighs about 270kg but the B500/4000 is 430kg (both with retarder) and we use both at 300hp but the high gvw bendy buses get the 6spd B500... inside there are the same components but clutch surface area is about 50% more in the B500/4000 and a wider sump...

BC Mack

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On 7/14/2017 at 11:00 AM, Bigjohn4300 said:

Thanks for the CCRS schooling! Has any issues been noted when using a non-AI exhaust manifold without the 460-high heat center section on a motor with tune, injectors and turbo?

Looks like you have a choice to repower to 375 HP with software and injectors or flash your current 300 HP to get rid of dead spots. 

The Allison makes you hesitate a bit about rolling the dice and installing over-size injectors, 5" exhaust, bigger turbo, bigger manifold and a smoke dial. Hate to see that short n' sweet little dumper sitting over a pool of oil.   

CCRS.pdf

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Attached is a guide for finding a pre-AI, CCRS, replacement camshaft.  We contemplated installing a 454GC5234A (PAI #891913) camshaft. Even though we are not done (exhaust work, tuner?, etc.) my buddy is certain he will not replace the cam unless it should die of natural causes, per level of satisfaction. As mentioned in the earlier post a PAI crossover was $1,980 for just camshaft.

Camshaft Cross-Over Bulletin.pdf

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Exhaust calculation. Working over justifications.

E7-12ltr running 1,680RPM @ 32 PSI boost creating 1,070 CFM exhaust @ 5PSI max (theoretical fixed) head pressure......

Exhaust size     exhaust speed (feet per second)      differential

1"                                         2,592                                              baseline

 2"                                          708                                                  366%

 3"                                          309                                                  229%

 4"                                          184                                                  167%

 5"                                           121                                                 152%

 6"                                            82                                                   147%

 

 

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I think I'm going to try the 375, but I believe I'm going to want more in the end. If it was a truck that the drivers use, I would be reluctant, but it's only me, the repair bill check writer (and my personal truck) so I believe it wouldn't be abused. My local Allison shop head tech is a personal friend from high school, he feels confident, on this model Allison, to around 1700 foot lbs owner driven

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On 7/18/2017 at 10:36 AM, Mack Technician said:

Attached is a guide for finding a pre-AI, CCRS, replacement camshaft.  We contemplated installing a 454GC5234A (PAI #891913) camshaft. Even though we are not done (exhaust work, tuner?, etc.) my buddy is certain he will not replace the cam unless it should die of natural causes, per level of satisfaction. As mentioned in the earlier post a PAI crossover was $1,980 for just camshaft.

Camshaft Cross-Over Bulletin.pdf

I gave some info to a guy on here who put a AC camshaft in  his AI engine. I will post our private message  and bulletins on here. His had no engine  brake so it made it easier I believe. Best I remember there are 4 different AC camshafts. 

Camshaft changes and part #.pdf

Camshaft changes ETECH ASET.pdf

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 Heres our conversation.  His question "  I have a 2005 cv713 vin-013505. I broke a valve last week and trashed a head but got it shutdown fast enought to save the liner and piston. It didnt brake a rocker or bend any push tubes.

It did brake the roller on the lifter and kill the lobe on the cam for the exhaust on #5. Can i use a cam out of an ac engine on mine to eliminate the exhaust bump on the ai cam?

I would like to swap my ai cam for an ac cam. I dont have an engine brake at all on this teuck. Is 454GC5236A a good one for me to use or 454GC5244."                                                                                                                                   My responce    "We have actually never done it here at our shop. My friend who has 2  CV's was waiting for a cam to go down and were were gonna do the AC cam swap. But he traded them in on 2 new GU's so we never got to try it.  Whats crazy is that the 5236A cam is  $860, the 5244 cam is $1469, the 5246 cam is $843 and the 5247 cam is $1586.  I attached the bulletins  on them. Wish I could help more . Number one thing is to check the "H" rings ( roller lifter holder)and make sure that it hasn't moved up in the block. If it were me Id try the 5246  camshaft but like I said I have never done this before. "                                                              His results       "Thanks for your information on the cams. I got the truck put back together a couple weeks ago. I put the 5246 cam in along with a mech pump e7 exh manifold, e7 350 hot side housing on my stock turbo and stage 1 rochester nozzels. Ive dropped egt on the same pulls by 250* and coolant temps from 210 to 190. The truck gives a slight puff of black smoke on the up shift and pulls very strong from 1300 rpm on up. Thanks again for the cam info. Thought i would let you know how things went"

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Btw the trans in this truck is a 4500rds, not a 3 series, that model, in that year truck, was available from Mack behind the 427 and lower ratings, but the 300 and 375 versions were supposed to be mapped for best performance behind the allison.

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The 4500 Allison should have enough capacity for the 375 HP rating.

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On ‎7‎/‎20‎/‎2017 at 9:20 AM, Bigjohn4300 said:

Btw the trans in this truck is a 4500rds, not a 3 series, that model, in that year truck, was available from Mack behind the 427 and lower ratings, but the 300 and 375 versions were supposed to be mapped for best performance behind the allison.

FYI

If I can throw out a suggestion, I recommend the group I use. Mike has his own recipes for Mack injectors. He services two Mack dealerships, one Mack independent and the owner operators. They turned around lots of angry, disappointed, AI engine customers for us. K & S will charge you $85 w/$50 core (plus soft/hard parts) instead of Rochester's $165 w/$100 core.

K & S got on the Mack modification map when they built the fuel system for Red Eye Express. It was a CH sleeper with a ridiculous amount of horsepower. A guy I went to tech college with was working at Cummins, Wausau, when Jimmy Stewart brought the Express in to run the dyno. He spun out too much so they told him to come back with a loaded trailer. He came back with a loaded trailer and still broke loose. At the Chicago Mack North American institute, where we factory trained, the teacher used the truck as a talking point. If Stewart was an honest man....he was reaching 10-11 MPG when he pussy-footed a load.   

I asked Mike about your set up. He would want to know the OE injector part number of the current 300HP engine and the OE part number of the injectors you would use for a 375HP. The only advantage Rochester is going to have over K&S is in the 460HP upper stage. Mike associates with Brad, at Rochester, and says they are tooled to push 460 to upper limits via honing technique.  

By design and plan they don't go with stages. If you pull into some shop with one cracked injector "stage so-and-so" they don't know who's stage is what or customized to what-where-who. If you lose an injector Mike can align you to your closest injection vendor for a specific replacement tip.

   

www.ksfuel.com

 

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The 300A uses 736GB419M . The 375A uses 736GB419M2. The AI400 also uses the M2's. The AI 427 and 460's use the M3 injector 

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2 hours ago, Mackpro said:

The 300A uses 736GB419M . The 375A uses 736GB419M2. The AI400 also uses the M2's. The AI 427 and 460's use the M3 injector 

Mpro, Your like an intellectual Swiss army knife.

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3 hours ago, Mack Technician said:

 

Mpro, Your like an intellectual Swiss army knife.

I try to buy the Mack Tune Up books every year. My oldest is  the 1972-1982 book. 

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Any updates on how this truck is doing fuel/power wise? Also a thought with the cam, can a machine shop grind and polish down the extra bump to eliminate the egr? I realize it's still labor intensive but maybe save a little on the cam purchase. 

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On 8/4/2017 at 5:54 AM, dcrow said:

Any updates on how this truck is doing fuel/power wise? Also a thought with the cam, can a machine shop grind and polish down the extra bump to eliminate the egr? I realize it's still labor intensive but maybe save a little on the cam purchase. 

I am getting together with the owner to do an audio file interview I will upload. If I had a dyno we would hit you with numbers, but we only have interpretation.

Sounds like a fine idea. It would be a minimal cut. I've never seen a camshaft under cut on a Mack, but I wouldn't hesitate to try it on someone else's truck. Barry Cam Service in Minnesota built a customer roller cam for the engine in my Cougar, so I'd try them first. 

Mack doesn't like folks cutting engine metal, predictably. My dealership was told not to install any crankshaft that was cut outside of Mack reman. Any squareness at a journal transition ends was expected to break. Considering the torque they drive out of a 12 liter crank I'd consider it good advice.

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The long awaited exhaust quote for upgraded 5" has arrived from Rock!!!!!!!!!!!

 

The custom Grand Rock, CV713, single run, exhaust part numbers are as follows:

  • MK-41112M2-5, 5" 2-BEND W/BELL FLARE & PYRO; ALZ  (front pipe)
  • MK-5110A-5, 5" 4-BEND W/LIST & WELDS OD/OD; ALZ    (rear pipe)

 

My Mack Dealership prices, w/mark-up, are as follows:

  • $206.99 front pipe
  • $221.03 rear pipe

 

Despite a couple requests they did not send a part number for the 5"-in/5"-out stack muffler so I'm going to go after that manually. No pre-cut 5" flex pipe included, so we will be cutting from bulk. We could use the listed dimensions from the Rock's standard 4", but I'm more comfortable cutting it ourselves since my remounts may adjust that length dimension. We are pleasantly surprised at the very reasonable price. When the parts get here I will attach pics.

 

 

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Awesome! Guess I don't need to email him anymore requesting part numbers, please post when you come up with a high flowing "quite" 5 in 5 out muffler

Edited by Bigjohn4300
Error

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Awesome! Guess I don't need to email him anymore requesting part numbers, please post when you come up with a high flowing "quite" 5 in 5 out muffler

Pittsburgh Power sells a high flow 5"

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Pretty close but just a bit louder. If a truck with one passed you you would think it's stock. When I installed mine I had some other exhaust leaks that I fixed at the same time and the truck was quieter. When I put a stock one back on I didn't notice any difference.

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