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Mack Technician

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

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First I'd like to send a note to any other clueless BMT newbies..... NEVER click the delete at the bottom of your "New Topic" page "moderation action" unless you want to lose all three pages of your post.  I'm dedicating this second post series to all truck owners who regretted buying an AI Granite and as a memorial for all the awesome tips from NELM and MACKPRO that I cast into eternal cyber damnation.  

Edited by Mack Technician

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Retired Gernatt aggregate hauler from upstate New York. 2005 Granite,  AI460, T318L 18 Speed, 200 series 4.35 Mack differential, 10MM single frame, 215" wheel base. 

After watching his brother suffer through DPF and SCR my buddy wanted a mid 2000's Mack Truck with no external emissions system in spite of potential low hole torque issues. He planned on 10,000 miles a year and couldn't justify maintaining an over-stuffed emission system.  

Gernatt pulled 107K, buddy was going to be pulling 90-100K loads hauling Feller-buncher, skidder and hot saw on tri axle low-boy.

 

Gernatt.thumb.jpg.23dcc2d57077586bb42b8a76ae2e0a41.jpg

Edited by Mack Technician

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New truck Loggin Dog couldn't tear his way out of a wet paper bag below 1,200 RPM's. My buddy was panic shifting at intersections, revving way too high for shift points and was 'Johnny Quick-Sticking' for a gear hole. Having come out a 1998 PLN 427, to this new high level of dissatisfaction, we made the choice to dig in.   

Edited by Mack Technician

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Downloaded Log (attached) revealed Loggin Dog had been drinking excessively for years..........

30 log.pdf

Edited by Mack Technician

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We weighed options and decided to try to cripple the Camshaft recirculation bump by reducing back pressure rather than installing a pre AI-CCRS camshaft. A pre-AI CCRS camshaft without a bump was $1980 and a complete kit was $3500, parts only.  Keeping in mind Mack will let you reuse ceramic rollers on new camshaft. Kit includes everything..... including new spring loaded push tubes.

31 Cam lobe profile.pdf

31 percentages.pdf

31 wavelength.pdf

Edited by Mack Technician

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First $250 we spent was having the last, latest, data file uploaded to ECM at the Dealership. That was the cheapest, instant, improvement we saw. LDog still had the original data file and a major drive ability issue. Occasionally, during acceleration, the truck would feel like someone was clamping the fuel line for 3 seconds and releasing it. I could never recreate the issue consistently, on demand, through some particular driving/accelerating pattern.

My buddy had a bread bag show up in his 1998 CH fuel tank once (previous owner actually used a bread bag to seal threads on a mis-fitting fuel tank cap because he was too cheap to buy the cap that fit). We changed the cap when he bought it, but by then a bag chunk was in the tank. That created the exact effect of Log Dogs software issue.  

Step 12b VECU software upload, problem gone.

Edited by Mack Technician
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Well its good to see you back. I was starting to think we were getting censored by some greeney  . What year truck was the exhaust manifold  from and what model.

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On 6/22/2017 at 10:48 AM, nelm1994 said:

Well its good to see you back. I was starting to think we were getting censored by some greeney  . What year truck was the exhaust manifold  from and what model.

NELM! The only Greeney was the "green-horn" who didn't realize delete means everything!

Mine was 2002 CH613. My old cohorts at the Truck Center said they grabbed manifolds all the way back to PLN..... Just watch out for CL chassis with E7 manifold which tilts upward.

In case you have no local source......... Manders Diesel, Minnesota, has a stock pile for $350. 

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Second, I did a sweep of the local Mack graveyards and found the fore-mentioned breather manifold (pre AI/AMI/AC) up at Scott's Northwood's Diesel, paid the man at the door $200, stripped it, bead blasted it to check for cracks and gave it an oil rub down. Perfect condition.

 

Exhaust.thumb.jpg.8fd845680ffe2564e327145dea0d5d80.jpg

 

Edited by Mack Technician

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"As a dog returns to its vomit, so fools repeat their folly."

Proverbs 26:11

High Priority...............need to stop the Dog from eating it's vomit. The Camshaft bump is responsible for sucking back filthy, uncooled, exhaust gas causing high soot return and poor burn.

The restrictor Manifold, 4" undersized exhaust pipe and restrictor turbo are all responsible for the back pressure needed to feed the 0.075" exhaust bump. 

Pre-AI manifold left, AI restrictor manifold right.  

594bf6b245cc4_41Manifoldprofilecomparison.thumb.jpg.d6bd57934e8772b87d7abe42e8b69204.jpg

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AI restrictor left                                                                                                E7-Etech right

Mounting height/depth/angle/position of turbo is perfectly matched, no adjustments needed.

594bf81a8a674_41manifoldcomparisonAIVs_Pre.thumb.jpg.37b5e77d22c043d24a0d092dfe9457e2.jpg

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Third, get rid of restrictor S300 turbo and replace with a breathable S400. Don't try to hog the S300 out to fit the breather manifold openings, doesn't work. There is not enough meat, they intentionally undersized the AI turbo casting.

 

Left side non-AI                                                                                           Right side Stock AI

594c1c536f852_41TurbocomparisonAI460VsPreAI460.thumb.jpg.f8daf5eb5c39161503e3a39212e796f2.jpg 

Edited by Mack Technician

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No need for explanation...... Injection/Turbo shop guy, Mike, did explain that the 30 gallon recyclable aluminum(in the background) was predominantly S300's. He showed us the internal bearing difference and sold my buddy. $1,200 for the new turbo, no core.

P.S- In case your unconvinced I will be listing the S300 turbo for sale shortly. Priced to sell...:D.

 

594c1d15799e5_41TurbocomparisonAI460restrictorVsEtech460.thumb.jpg.408a7ecf90e5f9cb51cc7bbc2f3ba614.jpg

Edited by Mack Technician

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Mike did try to do some housing swapping to check feasibility of swapping larger housings onto AI Turbo. It was a fail.

 

594c2462cf67e_41MrHookUP.thumb.jpg.1fdccada8d77d2175194e1d33c9a5ea3.jpg

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Fourth, get a set of over-size injectors. I used K & S fuel injection of Wausau, WI. They have a reputation for doing well on Mack stuff and keep cores so you can swap out at the counter for your new Injectors. No turning them in and wait. Mike requires the Mack part number of the OEM injector for the specific truck, then he refits the tips accordingly.

I told my buddy, before buying any specific truck, that we would play a bunch with AI427, but not as much with AI460. I feel increasingly bold about pushing more torque into the crank of this underpowered 460. The 1999 E-Tech 460XT was actually building 487 horsepower, but listing as 460. The block can take it.....460XT was putting out 1,760 Ftlbs of torque at 1,200 RPM. The stock AI460 is putting out 1,250 Ftlbs at 1,200 RPM.

Mike puts the injector life span at 5,000 hours before they lose performance. He says the CCRS is tough on injectors. Double hits per injection cycle. $85 per injector including soft parts kit, pretty affordable performance.

The injectors will add smoke on the take off, but clean up/spool up fast. I attached a video.

 

Loggin Dog.3gp

Edited by Mack Technician

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This is a great post! Only thing that would make it better is Dyno numbers. I've never dyno'd my 460

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On 6/23/2017 at 10:21 AM, Dirtymilkman said:

This is a great post! Only thing that would make it better is Dyno numbers. I've never dyno'd my 460

Thanks, I wish we had solid numbers too. Opinions are soft evidence. We have one truck dyno down in Wausau at the Cummins dealership, but generally very thin pickings around here.

Correction, made some calls, only one dyno left in Edgar, WI. $375 for the run-in. Doubt I could get the boss to pay that money to test a well-running truck.

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Fifth, get yourself a 5" exhaust system. I called Grand Rock and asked if they would build a 5" exhaust out of the jigs used to make the replacement 4" exhaust. Many calls later and negotiating through my Mack Dealership.........

 

Good morning Jason,
 
I did hear back from our engineering department.
 
It is feasible for Grand Rock to build all 5” versions of the pipes you requested.
 
There will need to be weld seams in both of the pipes you’re requesting, and have a GR level 4 difficulty.
 
This means a minimum of 2 week production time will be needed once the order is placed.
 
These are NOT stocked items, and will be Made To Order.
 
Please advise your local Grand Rock dealer of this, as there will need to be custom part numbers created.
 
If you have any further questions, please feel free to contact us.
 
Have a great day, and thank you for choosing Grand Rock for your exhaust solution needs.
 
Grand Rock Company
Joshua Stewart | Tech Support | Warranty | Returns
395 Fountain Ave. Painesville, OH, 44077                                                    
Ph: 440.639.2000 Ext: 115| Fax: 440.639.2010
TF: 1-800-321-3674
 
GRSigLogoEGlobeHDAsigLogo

 

Edited by Mack Technician

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After the fact... we appealed to have a pyrometer port as standard to the new custom part description. The picture in the Grand Rock book didn't show a 4" with pyro port. I had my parts guy at the dealership interpret that dimension off stock parts and get back to Joshua. From my conversation it will be top radius center of first bend south out of turbo. I asked Joshua for an exact dimension stack muffler with 5" in and 5" out to be included in quote. No straight pipes in our neighborhood.  

As of 6-23-2017 I have not received a quote for the custom parts. Doing follow-up Email first week of July.

 

I will need to know exact location dimensions if you want a pyrometer port installed.
 
Grand Rock Company
Joshua Stewart | Tech Support | Warranty | Returns
395 Fountain Ave. Painesville, OH, 44077                                                    
Ph: 440.639.2000 Ext: 115| Fax: 440.639.2010
TF: 1-800-321-3674
 
GRSigLogoEGlobeHDAsigLogo
 

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21 hours ago, Mack Technician said:

 

The injectors will add smoke on the take off, but clean up/spool up fast. I attached a video.

 

Loggin Dog.3gp

Looks like my ol 237.............:P

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