Its pretty much a fact that on pollution control vehicles, cats will make more power than without them. Ford Mustang Exhaust Upgrades
Long tube headers require a new mid pipe, and cat back system. So the cost is higher than just swapping for a better flowing set of shorty headers. Finding parts that work together might cause problems.
HP, and tourque will benefit higher up in the rpm range with the long tubes. There will be a slight loss of tourque down low in the power band. Overall the long tubes will give a larger total gain in horse power over the shorty. 5 to 15 HP more up top, and lightly more tourque than shorty's.
If you go for the long tubes, be sure to go with a all stainless system to prevent rust. In the long run you will save money if you plan on keeping your car.
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DSS 331 stroker, AFR 185 heads, Performer rpm 2 intake, Accufab 75 mm race TB, 30lb injectors, 80 mm Pro-M mass air, Extreme energy cam 266.
Anderson ford power pipe the big one, Ford motor sport shorty headers, Bassani x pipe custom cat back with flows, World class T5, center force duel friction clutch.
Its pretty much a fact that on pollution control vehicles, cats will make more power than without them. Ford Mustang Exhaust Upgrades
Long tube headers require a new mid pipe, and cat back system. So the cost is higher than just swapping for a better flowing set of shorty headers. Finding parts that work together might cause problems.
HP, and tourque will benefit higher up in the rpm range with the long tubes. There will be a slight loss of tourque down low in the power band. Overall the long tubes will give a larger total gain in horse power over the shorty. 5 to 15 HP more up top, and lightly more tourque than shorty's.
If you go for the long tubes, be sure to go with a all stainless system to prevent rust. In the long run you will save money if you plan on keeping your car.
OH So sorry, then I guess you can just hack it up a bit with a sawzall, and weld on some new hangers to get the right length.
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DSS 331 stroker, AFR 185 heads, Performer rpm 2 intake, Accufab 75 mm race TB, 30lb injectors, 80 mm Pro-M mass air, Extreme energy cam 266.
Anderson ford power pipe the big one, Ford motor sport shorty headers, Bassani x pipe custom cat back with flows, World class T5, center force duel friction clutch.
The only thing that changes is the mid pipe when you go to long tubes, the cat-back stay's the same, no manufacturer makes cat-backs specifically for long or short tube headers, they are all the same length. Thats not to say that may not have to play around a little to get the fitments right but you keep your cat-back.
bbk shorty headers and full length x pipe- hp gain 
