Truck Feels Weaker After Repairs & Addition of Exhaust & Intake

[LTRMC02]

I just completed putting new head gaskets and ARP studs in my truck along with all the other items and an S&B intake with 4" straight MBRP exhaust. I have a SCT tuner but no programs for it yet. I was expecting to feel a slight increase in power before putting in a tune but it actually feels a bit weaker than before the work and adding the exhaust and intake. It seems that the truck is running fine with no problems just a bit weak. Do you think opening up the exhaust with the stock tune will drop the torque due to the lower back pressure? I'll be getting some tunes when I can get up with someone, guess the first of the week.

Again, it doesn't seem like there is a problem with the way it is running but I was just expecting a slight increase in performance and am experiencing a slight decrease? The exhaust sounds good though

I'm debating on the SLR tune from Gearhead and the tunes by Eric at Innovative, I know this is always a debate but what's your opinions. I'm not looking for a race truck but a good daily driver with good bottom end torque and a good towing tune for when towing. More MPG would be nice too.

[SevenBrooksWelding]

Did you put all the accessories on or did you have someone else do it? Are all the boost tubes tight and not leaking? Are the up pipes sealed correctly on the manifold and at the turbo? Did you put in an EGR delete? Did it come with a new up pipe or a plug? Everything plugged up as far as connectors go?

I did mine a few days ago. A certified master tech at a dealership had done it before and left a few crucial things out. The previous owner had the work done, EGR delete, 4" TBE, SCT, Studs and gaskets... He didn't mill the heads. I ended up stripping it down and doing it right. The truck runs stronger now than ever. Same tunes and no other mods other than the original ones it had when I got it. The up pipe on the pass side wasn't even bolted up at the manifold.

As far as reducing backpressure goes, it don't work like a gasoline engine. Did you keep the cat? What kind of exhaust are you running?

[Evil Eye]

It's pretty amazing that such simple little things can cause such big issues with performance.

[BearDZ]

Originally Posted by LTRMC02

I just completed putting new head gaskets and ARP studs in my truck along with all the other items and an S&B intake with 4" straight MBRP exhaust. I have a SCT tuner but no programs for it yet. I was expecting to feel a slight increase in power before putting in a tune but it actually feels a bit weaker than before the work and adding the exhaust and intake. It seems that the truck is running fine with no problems just a bit weak. Do you think opening up the exhaust with the stock tune will drop the torque due to the lower back pressure? I'll be getting some tunes when I can get up with someone, guess the first of the week.

Again, it doesn't seem like there is a problem with the way it is running but I was just expecting a slight increase in performance and am experiencing a slight decrease? The exhaust sounds good though

I'm debating on the SLR tune from Gearhead and the tunes by Eric at Innovative, I know this is always a debate but what's your opinions. I'm not looking for a race truck but a good daily driver with good bottom end torque and a good towing tune for when towing. More MPG would be nice too.

That seems a bit odd. I put a S&B intake and MBRP exhaust with no cat in a few years back and immediately noticed an increase in power. It must be something else going on.

[LTRMC02]

Originally Posted by SevenBrooksWelding

Did you put all the accessories on or did you have someone else do it? Are all the boost tubes tight and not leaking? Are the up pipes sealed correctly on the manifold and at the turbo? Did you put in an EGR delete? Did it come with a new up pipe or a plug? Everything plugged up as far as connectors go?

I did mine a few days ago. A certified master tech at a dealership had done it before and left a few crucial things out. The previous owner had the work done, EGR delete, 4" TBE, SCT, Studs and gaskets... He didn't mill the heads. I ended up stripping it down and doing it right. The truck runs stronger now than ever. Same tunes and no other mods other than the original ones it had when I got it. The up pipe on the pass side wasn't even bolted up at the manifold.

As far as reducing backpressure goes, it don't work like a gasoline engine. Did you keep the cat? What kind of exhaust are you running?

I did all the work myself and feel pretty confident everything is put back right. I can't hear or feel any intake or exhaust leaks and the truck seems to run find but definitely doesn't feel any more powerful than before all the work and maybe slightly less torquey at low RPM.

I put a 4" turbo back MBRP, or so they called it but it necks down to 3.5" at the turbo connection, no Cat or Muff. I'm not experienced with diesels but hoping that opening up the exhaust and still running the stock tune is the reason for the sluggish feeling. I haven't rode or drove a strong 6.0L yet so I'm not sure what one should feel like. I bought this truck used and drove it 2weeks before the EGR cooler gave way and started pouring steam so I've been working on the truck the majority of the time I've owned it Yeah EGR cooler is gone now and new up pipe installed, CAT coolant with a filter kit installed as well so hopefull it's at least reliable now.

[LTRMC02]

Originally Posted by BearDZ

That seems a bit odd. I put a S&B intake and MBRP exhaust with no cat in a few years back and immediately noticed an increase in power. It must be something else going on.

Did you already have a tune on your truck or was it factory tune?

[BearDZ]

Originally Posted by LTRMC02

Did you already have a tune on your truck or was it factory tune?

It was completely stock. This seems a bit odd.

[LTRMC02]

Originally Posted by BearDZ

It was completely stock. This seems a bit odd.

Maybe I've just gotten used to the high performance power of my dad's 93 chevy half ton with a 4.3L while I had mine down working on it

Anyone ran the SRL tune from Matt at Gearhead? I'm leaning toward his tunes. Looking for better bottom end torque more so than speed.

[Evil Eye]

You will likely feel a slight bit more turbo lag since the exhaust flows better and less back pressure. Once you get some tunes, it will really wake your truck up. I have heard GREAT things about Matt's tunes, particularly the SRL+.

[LTRMC02]

Originally Posted by Evil Eye

You will likely feel a slight bit more turbo lag since the exhaust flows better and less back pressure. Once you get some tunes, it will really wake your truck up. I have heard GREAT things about Matt's tunes, particularly the SRL+.

Hopefully turbo lag is all it is and maybe a good tune will help it spool up quicker. I have some tunes coming from MKM Customs that are freebies since I ordered all my parts through them, have you ever heard anything about their tunes?