TAS05CTD610

Ok now I know it's a Federal offence to remove any of the EPA crud and all that junk. But this is an off road question.

How much of an EGT drop do you get from taking the cat off?? I was thinking of running a Tri-clamp system to change pipes out in under 5 min if I needed too. Is it like a 100-200 degree drop? or is it around 100 or less? I'm currious as to anybody that has run with, or without what the temps have been? I'm not into super high performance but if it would drop 100 -200 degrees it's all the less I'd have to worry about? I do tow and may have a 36 foot 5th wheel in the near future, so I def. wanna make sure to keep the temps down.

Also on the cat back trucks, the muffler is only like 15" long or so? I know with the cat on and that muffler, it sounds killer. If I take the cat off, would another 15" muffler sound good? (this is an MBRP system) My dad has the 30" system on his 99 and it's good, but dosn't sound as throaty as mine (maybe the kitty makes it this way, 30" on his) Maybe mark will chime in. I don't want it the loudness it is with no cat, that's just too much but I don't want it quiet, I want the happy middle.

wap

Extreme, I am runnin no cat no muff, as far as how much drop I cant tell you but it definately should drop. I sure you have read the same things that I have but they say the most drop you can get is puttin an aeroturbine on the downpipe and goin straight from there. They say it runs cooler than a true straight pipe but thats to much money for me to test it out.

Lary Ellis (Top)

You don't want to remove the cat on an 05 truck, it will get you no gain at all. Not to mention that third injection event happens just to increase the heat in the catalyst to keep things clean. The 05's run hotter and they are supposed too.

TAS05CTD610

I've heard that but you know how you get one person saying they can get really hot, and one saying no...... I can see temps of 1100 1200 stock and haven't towed the big trailer yet. Little one yes, but not the big one. Temps are right around that when pulling hills although they get up higher when running hard (I'm one that will maintain 75mph no matter what hill is in front of me Just currious. I didn't think they had much back pressure or that, so if it's not worth it, then I ain't doing it. Gota love a site that not only gives you info fast, but it's correct.

RamWheelsBy4

TOP please don't wack me for answering the question honestly.

I have tried both ways. Generally speaking it is probably not worth the effort and I try to obey laws, regardless how I feel about them. I do believe that there is an additional EGT reduction with the cat off, but it is not over 100* and probably less than 50* for the cat alone. I had mine off for a while when the new downpipe was installed and took pictures of the inside. I did not believe that it was very restrictive even with my mods. But I do have to add that after looking inside it definately does add some back pressure and impede exhaust flow. That honecomb looks solid for the entire length of the large diameter area.

Lary Ellis (Top)

Your truck runs hotter than the older trucks and it is designed to do so, you will see everyday temps that would worry the owner of an older truck but are perfectly safe on your truck.

TAS05CTD610

Just wanted to check with the chip on the way wanna make sure I keep the EGT's safe. I've heard that 1300 is fine for them but any over I should keep it down? I want to know what the Max sustained is that I could run without hurt. If it's 1300 so be it, then i can know I can hit higher but back off faster. Just currious what's high on thse motors. My dad has had his very high before gagues (you know drive it like you stole it) I think he's going to be surprised to see what he's hit with the gauges.

Tom

RamWheelsBy4

Not sure how to answer that, my highs have all been at the track so they are for a few seconds only. Mine with just air intake and exhaust would get to 1300+* on WOT. With first group of performance boxes, I saw 1500+* on sustained WOT. After the last round of mods and performance stacks I have seen 1700+*(This was on the TST remote, the Autometer was pegged ) for a second or so at the track.

Highway empty or light load I rarely see over 1200* and then not long. I don't tow anything heavy, so I am sure that would make a difference. But the more load I put on it, the quicker the SPS66 kicks in and cools things down .

It seems that 1300* on the 600s up is kind of a sustained max, and I am not sure I would even be comfortable with staying that hot for a long haul.