Smarty Jr. Is being added to scrap truck part pile!!

[mpaulson]

Truck is in for the second head gasket in 11months. One at 178,000kms and now again at 201,000 Kms. I ran the Edge juice on the towing setting with stock timing from the 10,000km mark up till about 170,000kms with no problems. I've been running the Smarty Jr. on the tow setting with stock timing and stock torque management, and this is what I get!!! When I get the truck back, the Smarty will be added to my pile of scrap truck parts!!! With a bunch of research online today, I've concluded that Smartys should never be used on the 6. 7's, only good on 5. 9s. The only advantage the Smarty gave me was about 100-150 degrees cooler etg's, but running high boost to get this is the disadvantage for the stress on the turbo and the excess cylinder presures causing gasket problems. It's not like the egt's were unreasonable with the edge, I could tow at 24,000# with lots of wind drag and average 950-1000 degrees in the manifold, I'll live with extra egt's and save on the $1,800. 00 head gasket jobs every 23,000 Kms. It made 0% difference on mpg anyway, as did the deletes in the first place.
Bottom line is, if you are thinking of a Smarty for your 6. 7, don't
do it!!!!

 

[Cummins12V98]

That is a bummer!

Did you add studs?

I am happy with mine right out of the box.

 

[RVTRKN]

That was my first thought, time for studs. Unless you have a specific reason to add performance to a CTD, like sled pulling, drag racing and other reasons that will require them. I don't see the advantage to them, and the reason is the CTD is a well designed engine platform, yes they have had problems over the years, but comparing them to the competition there is none better. When you deviate from the CTD stock platform and program for higher HP/TQ, you run into issues like the OP is reporting.

 

[CUMMINZ]

I love my Smarty 67

 

[NIsaacs]

Unless you have a specific reason to add performance to a CTD, like sled pulling, drag racing and other reasons that will require them. I don't see the advantage to them,

Can you say stock 1st and 2nd gen? They need help or stay in the slow lane like this speed limit sign suggests



Nick

 

[AH64ID]

Are you sure the timing was set to stock? The EGT drop tells me that you had advanced timing.

 

[RustyJC]

EGTs will drop with higher boost levels as well (which were reported by the OP).



Rusty

 

[AH64ID]

They will, but that amount of EGT drop he is talking about seems more like timing than boost, it would take a lot of boost to make the EGT's drop that far.

 

[mpaulson]

Yea, did ARP studs on the first replacment. I don't bag my truck, I never race, the throtle has never hit the floor in this truck. The only reason that I started down this road with a chip was the claims of major milage increases like 9 mpg, and this would allow me to do the deletes. I didin't even get half a mpg change!!! I do tow reasnonably heavy, 24,000# for 10,000kms+ a year camping. I was towing a measly 7000# when this happened and going up my local hill and it was 31 degrees celsius, that's about 87 F. I won't deny that I like to keep my speed on climbs and was keeping my speed on this climb, very short climb, and hit 32 psi. I couldn't handle setting it to stock, I would barly maintain highway speeds, especialy with any kind of a head wind, I'd rather stay home then. The Smarty always has me around 25-28psi boost just to run flat ground at about 780-900 degrees, where as the Edge had me in the 15-22 psi range and 860-1050 degree range which is an exeptable temperature while towing. I only tried the Smarty to see if the mileage would increase and the cooler egt's wouldn't hurt either, or so I thought. I tried the timing change, bumped it up one level, before the first gasket failure and thought this was why it failed. That was only for a week, and not towing. Then I went back to the "stock "timing and have left it there ever since, and yes, I did set it to stock in the smarty and "wrote" it before it reprogramed the truck's ecm. The egt drop that a I am comparing to is against the Edge on "tow" setting, not stock.

 

[NIsaacs]

I wonder if the difference in boost and EGT's between the Edge and Smarty have anything to do with your 4. 56 gears? Or did you have the 4. 56's with the Edge too?



Nick

 

[Bob4x4]

I have seen plenty of failed head gaskets on the 6. 7's with any programmer-with out exception the owner always says It was just on the tow setting. Each customer I have talked to says the installer said there was no risk to doing deletes and running a programmer.
With no wastegate on the turbo what will the boost end up being pulling a heavy load up grades ?

 

[Bob4x4]

I wonder if the difference in boost and EGT's between the Edge and Smarty have anything to do with your 4. 56 gears? Or did you have the 4. 56's with the Edge too?

Nick

I avoid playing with 6. 7s in Cali but with the 5. 9s the smarty always has less egts than the edge for the same amount of power on the common rails

 

[mpaulson]

I haven't run the edge with the new gear ratio yet, will next week once the truck is back. All comparisons in previous post are with the 3. 73 ratio. I don't expect much to change though, I just use 6th gear at 2100rpm instead of 5 gear at 2300 rpm, so only a 200 rpm difference at my 'normal" 110km/h hiway cruising speed. I do wish I was at the 2300 rpm mark though as I feel like it lugs a little more with the 200 rpm drop. The nice thing is with the 4. 56 gears is you feel like you are driving around in low range starting out from a stand still, but it sucks when you do want to go faster on the hi-way empty for longer distances.

 

[CBlack]

I ran a Smarty on mine and had zero issues. Which version software on the Smarty are you running?

The issues of blown head gaskets on these engines has more to do with drive pressure in the cylinder than anything. The stock VGT is the main culprit.

Get rid of the VGT, upgrade to a S400 framed turbo along with a new MLS gasket and 625 studs... problem solved.

 

[AH64ID]

Added fueling with stock timing is asking for more drive pressure than with advanced timing, but I am not sure if it's enough to create a low enough flow to boost cylinder pressure to the point of HG failure, especially with 425's. High drive pressure does not cause blown HG's, it's just the indicator of poor airflow thru the head, leaving more residual air and higher cylinder pressures.

I would suspect something else caused the 2nd gasket to fail, especially with studs.

He would hate a S400 with a 24K GCW while towing. The HE451 would be a great upgrade, but at ~400 rwhp and with good VGT tuning the HE351 can be used without issue.

 

[CBlack]

Added fueling with stock timing is asking for more drive pressure than with advanced timing, but I am not sure if it's enough to create a low enough flow to boost cylinder pressure to the point of HG failure, especially with 425's. High drive pressure does not cause blown HG's, it's just the indicator of poor airflow thru the head, leaving more residual air and higher cylinder pressures.

I would suspect something else caused the 2nd gasket to fail, especially with studs.

He would hate a S400 with a 24K GCW while towing. The HE451 would be a great upgrade, but at ~400 rwhp and with good VGT tuning the HE351 can be used without issue.

What is his altitude while towing?

Didn't think of that when posting earlier... at sea level or close to it, a S400 on the 6. 7 is great.

 

[mpaulson]

The smarty was just updated a month ago, so whatever was out a month ago is what it has. I didn't do the update,NADP did it for me. I just feel that the fact that I ran the Edge and on the tow setting with stock timing for the first 170,000 Kms with no issues, and now two gaskets with the smarty in 23,000 Kms, I'll stick with the one that I have proven to myself that I can run for a long time without it giving me problems. The head is getting machined flat this time as well,it wasn't out enough before to warn't it, so they say anyway.

 

[AH64ID]

Looking at the Edge info their tow setting is 40hp, and when you go to stock timing I bet that drops. The Smarty Jr on tow is 70hp and the timing will take some of that out.

So you were running a bit more power with the Smarty, thou it still doesn't seem like you were doing anything that should have been an issue with studs.

 

[NIsaacs]

at sea level or close to it, a S400 on the 6. 7 is great.

Wouldn't he loose his exhaust brake?



Nick

 

[AH64ID]

Wouldn't he loose his exhaust brake?

Nick

Yes, and I know the S400 is popular with the street/strip crowd but I haven't heard it being used in too many towing applications. It's a pretty big turbo to spool with a load.