91 sho owner looking for some help

[jamesdh1974]

I have a 91 mtx 3.o that has true cold air intake out the fender. the exhaust is stock headers no cat to a 3 inch straight pipe to the factory duals with fart cans I am getting actual mufflers soon. it is silver with blue Shelby stripes down the center. am I killing it by the exhaust being so open?

 

[luigisho]

That car sounds familiar. Maybe some low end torque loss but I wouldn't worry about it, unless it's too loud for you or it needs to pass emissions.

 

[sperold]

No, you are not killing it, but likewise, you are not really helping it either. The cold air intake system does not help much as the original induction system is very good. The exhaust "openness" does not help with performance (and no one really knows why) but it does not have a detrimental effect on engine life or anything like that.
You used to hear urban myths about cold air moving too quickly up the exhaust system (after shut-down) and warping exhaust valves, but that was nothing more than a lie, and not even a good intention lie.

 

[jamesdh1974]

No, you are not killing it, but likewise, you are not really helping it either. The cold air intake system does not help much as the original induction system is very good. The exhaust "openness" does not help with performance (and no one really knows why) but it does not have a detrimental effect on engine life or anything like that.
You used to hear urban myths about cold air moving too quickly up the exhaust system (after shut-down) and warping exhaust valves, but that was nothing more than a lie, and not even a good intention lie.

No, you are not killing it, but likewise, you are not really helping it either. The cold air intake system does not help much as the original induction system is very good. The exhaust "openness" does not help with performance (and no one really knows why) but it does not have a detrimental effect on engine life or anything like that.
You used to hear urban myths about cold air moving too quickly up the exhaust system (after shut-down) and warping exhaust valves, but that was nothing more than a lie, and not even a good intention lie.

 

[jamesdh1974]

No emission worries. Ya the only thing I have noticed is not as smooth bottom end but it screams once it hits 3850rpm. I will post some pics soon. It has the national sho members sticker in it as well. Might be why it sound familiar. And I love the sound!! It's angry and fun!!

 

[luigisho]

I think I remember pics of it posted here over the years. A little back pressure with a more restricted oem setup on the exhaust seems to help with the original tuned torque curve. Opening the exhaust trades some lower end grunt for a little gain on the higher end.