pik

How much HP will I be leaving on the table if I just put true duals on my 79 (also remove the cat)? It has been recommended to me to only use ceramic coated headers, how much HP will I get for the $300-$400 for ceramic headers? I expect 20 to 30 HP with just the duals no cat, is this realistic?
Thanks

garagedweller2

The headers help alot, but the ramshorns aren't that bad at all

page62

The ram's horns aren't bad at all. And headers can be a real pain in the butt to install!

Fevre

The higher the hp the greater the gains from headers, on a stock eng you might get 10-15 hp.

Chuck Harmon

How bad are they? They are great for holding things down in high winds!

Chuck

garagedweller2

Chuck, where's your sig?!

leichtigkeit

for pure hp the headers are better, but the gain is in the high rpm. for a balance between hp and torqtorque then ram are actually quite good.

UKPaul

I fitted true duals onto my stock (tubular) manifolds & about a year later fitted Headers. I noticed a much bigger difference after fitting the duals than I did after fitting the Headers. The stock manifolds on mine (tubular '81 type) seemed to be restricting flow at the top end, they felt fine low & mid-range rpms. Headers have made an improvement to the top end, but I can't say that I've noticed any difference at lower engine speeds.
I can't give any hp figures, but fitting true duals was the single best power gain I did. Really woke it up. If you're thinking of Headers then do it all at once. My Dynomax Headers were an easy fit (no aircon to worry about, if that makes any difference) but plumbing them into the dual pipes was the tricky part. I ended up making another exhaust system as it was easier than moding the existing one to fit the Headers!