Emmisions vs. non-emmision Heads

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
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Dallas, GA
They will make the option and both report the same flow numbers such as the TFS TW and Track Heats as well as the AFR 165-185 also come with the same emmisions and non-emmisons options and report the same flow.

Does it make a difference in power?
 
That was my first thought but then again with the passages especailly on the second back that lead to the EGR and smog pump ports could cause turbulance.

The reason is that I have TFS Twisted Wedge heads but I am not going to run EGR or A/P on the new motor, just wondering.
 
I doubt there is a real definitive difference between the two. I personally chose the "smog legal" heads for better resale value when I go to upgrade. You know not everyone has deleted their smog pump or wants to. Just gives me more options later:nice:
 
5spd GT said:
I doubt there is a real definitive difference between the two. I personally chose the "smog legal" heads for better resale value when I go to upgrade. You know not everyone has deleted their smog pump or wants to. Just gives me more options later:nice:

Same performance with a better resale value. No reason not to get the emission heads..
 
The biggest diffrence is they took the heads installed them on a car and proved that their product has no affect on emissions. Then you get the paper work and sticker that goes along with it. So if you fail emissions you can prove with your paperwork that the heads had nothing to do with it.