Ludo when you did the 3" did you notice any drop in the bottom end torque?

One of the exhaust kits available is a 3" setup to the end tip, not much of a selection out there for this. When I do pick one (the other is a Flomaster) the goal will be to keep the tone down so it is not too loud pulling out onto the street (neighbors & leaving at 0400).

 

Hi Steve,

I didn't noticed anything, i've made the first change when i bought it.
It had an i believe flowmaster damper with a dual exhaust and they made it come out before the right axle on the side, side exit.

For the same reason as you, my neighbours, i used to begin my day like you somewhere between 04:00 and 05:00, i changed it as soon as possible, could buy the Simons Stainless free flow exhaust and piping overhere, so i made it from the cat from 2.5 to 3inch and all the way to the back, going over the axle.

2 things i noticed was the reduced noise at idling and i got rid off the drone there was before, much bettter, when you're driving distances, could hardly have a conversation in the cab before.

I moved to my current house, and noticed when i had it running and got indoors, it still was a bit too loud when idling, so i got 2 free flow rear dampers of a nissan 300ZX for free and put them on at the end, they are my end tips, i had to go back to 2.5 inch for those, but i read it should be better for the torque range, because off the backpressure i had lost with going to 3inch all the way.

For this change, i can't tell the difference, i think it's marginal, too little too notice.

Did not have the time yet, but i'm going to make some other PL Launchers and like you, play with some ball valves.

Thanks for keeping us updated Steve, greetz Ludo.

 

When i followed the crowd & did a 3" cat back on my 1st ram i lost a good amount of bottom end torque. Added back in a spacer with a 2.75" opening and got some of it back. I am planning to not weld anything up (nut & bolt band clamp for now) before experimenting with the setup. Band clamp here tomorrow, will see about the install soon after.

 

Still no y-pipe install... the guy I wanted to do the work is not available on the weekend until the end of the month, so... will probably either have to do it myself (getting lazy) or find another shop, or have someone else there do it.

Motivated by the additional power my truck now has vs a couple of years back, I decided to see how the Jeep Trans controller would do with the extra bottom end torque I now have. So I swapped it back in & took it for a spin. Definitely can run this trans controller now with the added power and the trucks setup (3.55's & e-rated 265-75-16 tires). It is much better then it was before the current mods. But... it still shifts the same as it has always done, which is one of the things I hated about it. Soooo.... I dove into HPTuners trans tables to see if I could fix that and make it shift how I want it to shift. Found a parameter for the 4-3 downshift that seems to have given me control over that 4-3 downshift. The parameter is [ECM] 25024 found on the shift general tab. I bumped the 2.0 entry from 37.0 to 44.0 and now that downshift is much better. I not sure if need to go back and update the one for the cruise control table as it is indicating a pressure change, the data however in the 2 tables (one mentioned earlier & the CC 4-3 downshift one) were the same.

With the jeep trans controller swap & the 5th gear, truck now cruises at 70 mph at 1768 rpms per the grim jeeper calculator Gear Ratio Calculator Now happy with the trans shifting with the jeep controller. It will be interesting to see how it affects mpg's. Others claimed a 1.0 mpg increase. These days if I am keeping my foot out of it, will get mid 17's. Overall still pretty happy with the performance of it these days, beating on it will still get me mid 16's for mpg's.

 

Hi Steve, you need to get some miles on, it's a self learning computer, it wil change a bit, or adapt to the driving style.

Happy to see, you have more power to run it now, curious if it will save you gas.

Happy testing, greetz Ludo.

 

The drive into work showed me the trans tuning part still needs work. Gonna shelve it again & go back to the Dak TCM for now so I can get the y-pipe done, learned some things while attempting to get the downshift working like I want it. One being at 70+ mph it does not want to downshift like it does at 60. I adjusted the same table but at the higher tail shaft speed, test drove it and it seemed to behave as expected but did not this morning on the way into work.

I know mpg's were in the mid 17's with a specific tune (will go back to it before the install). Hoping to get it done Saturday (work travel this week).

 

No y-pipe install yet, so did some trans tuning yesterday, still working to get the jeep TCM shifting the way I want it to. The problem with what I see is the gearing on the truck plus the 265-75/16 E rated tires make running the jeep TCM in the OEM config miserable. It requires a lot of throttle to get it to downshift. With my mods on the motor, opening up the throttle for a downshift will drop MAP to 0 and it slowly accelerates in 5th gear, sometimes never downshifting regardless of throttle input. Have not figured out why it does this but that may be a wasted effort since I want the downshift to occur. Once there is a downshift & MAP goes up (vacuum), it motors on as expected.

I did learn (again) yesterday that the fuel economy parameter, [ECM] 28572 - Trans TPS Fuel Economy directly impacts overall performance, engine & trans. The default value is 0.75, when set to 0.50, SOTP power drops, trans shifts become "lazy" & the driving experience is bla. When set to 0.94 the truck (engine & trans) wake up and it is way more fun to drive, SOTP power goes up.

My last download had changes to 3 tables, the 4-3 Downshift (Normal) - (shift general tab, ECM-25024), Trans Gov Press (Normal) - (Shift Pressure tab ECM-25004) & Trans Gov Pressure 4-3 (Cruise) - (Shift Pressure tab ECM-25031). I adjusted the pressure at the 2000 tailshaft speed to 44.00 & lowered the tailshaft axis from 2000 down to 1900. This change got the trans to downshift at a lower throttle input like I as shooting for.

I have one download to do this morning that has more minor tweeks to the tables above & am hoping it will be good to go. Did "mostly" control the right foot for the commute to work, with all the trans tuning and heavy throttle events, I still got 17.4 mpg over 341 miles. Was shocked by that.

One last thing, I did note that it was running rich at the 1600~1700 rpm range with the trans in 5th so I tweaked the fuel there to get the LTFT closer to 0, that still needs work.

 

Y-pipe install done... drop in mid-range, not so much on bottom end, engine is doing a relearn & currently running rich according to ltfts. Will give it some time to adjust and report back

Gave a co-worker a ride back from dropping is ride off at the dealer this morning, his first comment was the truck sounds healthy :-) Rolled into it and he was impressed (he is also a "retired" motorhead, no longer active on the cars)

 

Did a road trip to the motorcycle races today, MotoAmerica. 112.6 miles RT, 5.711 gallons for 19.716 mpg. Speeds were in the 54-70 range across both trips (coming & going). I had a couple of passes on the back roads and one pass on a nasty hill climb (near full throttle with no downshift).

this trip is an exception and not the rule... The only reason I filled up was I saw the number of miles driven had only used 1/8th of a tank & was sitting at 110 miles when I noticed it. In my trucks history in my possession, I have had only 2 tanks greater than this 19.7 mpg tank. Those were also exceptions and not the daily commute. Both of those tanks were before I did the fuel pump swap. Since doing the fuel pump swap I have had just 1... just 1 tank at 18 mpg, everything else was mid 17's or below.

Next week I will try & keep my foot out of it and get a good comparison mpg wise.

 

Measured the pipe diameters on both legs of the y-pipe, they are necked down to 1.75", 2" else where. The addition of the updated 2" magnaflow y-pipe is definitely worth it, couild build one if you have the tools & skills but should be 2" at the collector end to the merge pipe. the diameter should match the outlet of the header, in my case it was 2" (jba shorties)