Intake manifold swap?

MiamiSilverado1500 · June 13, 2017

It does. But you.probably won't see much gain in hp I think just torque and throttle response

Torque and throttle response is good by me. It's a truck not a racer so it will suit its purpose. Better flow in and out and a tune should also help mpgs if by a tiny bit or at least maintain them at their current spot which are good by the numbers that I've seen here on the forum.

Regarding the exhaust I'm considering going full straight exhaust. When the headers go on they will be accompanied by a 3 inch offroad Y-pipe.

Nasty · June 13, 2017

You will hate it. Way to loud. And you'll need afm shut off

07Softail · June 13, 2017

It does. But you.probably won't see much gain in hp I think just torque and throttle response

Manifold might flow a bit more from the larger inlet but the ports and runners are the same. I will guarantee that running a straight exhaust no muffler with headers will be short lived. These engines are loud as FVCK with headers and even catbacks don't help much quieting them down. I would suggest running the stock exhaust with headers.

RT

Edited June 13, 2017 by 07Softail

Nasty · June 13, 2017

That is the best thing I've heard all week. But if for sure get catted headers

MiamiSilverado1500 · June 13, 2017

You will hate it. Way to loud. And you'll need afm shut off

Why would I need AFM shut off? I want to keep it due to the fact that I spend so much time on the highway anyways. If there really isn't that much of a difference between AFM and being in V8 mode then I'll have it deactivated through the tuner. If that's the case.

MiamiSilverado1500 · June 13, 2017

Manifold might flow a bit more from the larger inlet but the ports and runners are the same. I will guarantee that running a straight exhaust no muffler with headers will be short lived. These engines are loud as FVCK with headers and even catbacks don't help much quieting them down. I would suggest running the stock exhaust with headers.

RT

Right now I'm running stock headers and cats with the mid resonator and chopped off everything before the big muffler and running the exhaust tip out right before the rear tire. So it is much louder than stock that is for sure. I want as much flow as possible and if it's going to be that ridiculously loud then I'll add a muffler somewhere in the middle.

MiamiSilverado1500 · June 13, 2017

Check my profile for the pics in the gallery so you can see what I did to the exhaust. It's nothing new, many others have done the same.

Nasty · June 13, 2017

I'd you have anything other than stock exhaust. You will have the helicopter chop when the truck goes into v4 mode. I had mine shit off

MiamiSilverado1500 · June 13, 2017

I'd you have anything other than stock exhaust. You will have the helicopter chop when the truck goes into v4 mode. I had mine shit off

Ok, is there really a difference in mpgs between stock setting and permanent V8 setup??

Nasty · June 13, 2017

Not much. But if you're wanting to do all this work. Mpg should b3 your last worry

I have afm shut off and I get about 24 25 mpg on freewaygoung about 70 75

MiamiSilverado1500 · June 13, 2017

Not much. But if you're wanting to do all this work. Mpg should b3 your last worry

I have afm shut off and I get about 24 25 mpg on freewaygoung about 70 75

I'm doing all of this work trying to get the best of both worlds. I know it won't be exact but if I can get close to my goal then great. If the difference isn't that great then so be it. What do you have done to your truck?

Nasty · June 13, 2017

Drop, afm delete, smaller tires, shift point adjustment, muffler, and cold air intake.

Doing l86 manifold soon till the Maggie comes

MiamiSilverado1500 · June 14, 2017

Definitely starting to consider the DOD/AFM delete after reading more about other people not really noticing a difference in mpgs, only minimal at best. Also adjusting the shift points would be great. I hate automatics to be completely honest. I love that I have the work bench with no center console. In the future I might just swap out the auto and drop in a manual transmission.

What cold air intake did you go with?

Nasty · June 14, 2017

Shift points were adjusted slightly because I have a smaller diameter.tire

Afe momentum gt

ruby15z71 · June 14, 2017

Difference when tunes from v4 to v8 is barley noticeable. Buddy of mine is on 22" reps with 34" Nitto Terra Graps, LT headers, corsa cat back, corsa intake and tune with the 6.2L and he gets about 19-21mpg highway. He said no difference from when he had v4 or not. Also the older model 5.3s with AFM had issues with the lifters collapsing due to constant shutting off of 4 cylinders. That's why everyone recommends a tune and shutting it off via tune tonprolong the life of the lifters. So far no issues with the 14* trucks yet that I've heard but haven't really seen anyone get over 100k either. I also have the aFe momentum GT and love it. I do recommend you get a closed/sealed intake box vs the open box cause studies show the open box has higher IATs. I know you said it's a truck and you like loud but straight headers out is obnoxious. The same guy mentioned above with the LTs (with high flow cats) and a corsa exhaust could be heard pretty far away. (At least 1/8 mile). Here's a couple links to the corsa and headers with LTs and high flow cats. Keep in mind these are all the 6.2 with American racing headers and cats. Imagine how loud timeouts be straight headers haha