Exhaust and Air Induction

[owls_rayne]

I have two questions:
First, is that I'm deciding on buying a cast iron exhaust manifold an having the the runner bored and cleaned out for better for better flow I already have a turbo muffler on my normally aspirated '04 Pt Cruiser. From what I have read on this forum, headers don't have the longevity and are subject to cracking.

The second question is it possible to put a larger fuel injector body on the '04 PT Cruiser for more power and better fuel economy.

Owlsrayne

[quicksilverdon]

Headers do have mixed reviews. I don't recall hearin of any problems with Borla headers, just Heddman, but I could be wrong.

As to second question - More power and better fuel economy are usually opposing goals - larger injectors could produce more power, but definitely not better economy, and I'm not sure what the engine computer would do with them....
Buy an air intake. If you get a "cold air" one, you'll get more power, if you get a "short ram", better mileage and either way you'll get less hesitation when you give it the gas.
Keep your tires pumped up - I can notice when mine are 3PSI low, the car seems more sluggish - and it helps mileage, too.