390 4V headers, which to buy?

[Arie_de_Leeuw]

I am from the Netherlands and got me a 1967 Bird last week. Car has some work and i need some advice on wat headers to buy. Gaskets of bot the exhaust manifolds are leaking and was thinking of replacing both manifolds with headers. Which ones should i buy and will they fit the existing remains of the exhaust. I am using the car once or twice a month, it has a stock 390 4V.

 

[OneAmongOthers]

They will absolutely not fit your existing exhaust system as it was designed for the exhaust manifolds and not header collectors. Also you will be very hard pressed to find a set of headers (shorty or long tube) that will fit with this era thunderbird without modifying them to get past the center cross member, and honestly I would just stick with exhaust manifolds over headers. The horsepower gain you will get is minimal. If you want sound get a decent sized exhaust system. 2 1/2 inch or 2 3/4 will produce a nice sound. Add in some decent mufflers like flowmaster, magnaflow etc...

 

[Arie_de_Leeuw]

Thank you!

 

[OneAmongOthers]

Also a larger exhaust system will let the engine breathe easier resulting in a slight power gain too. If you do try to remove the exhaust manifolds be warned! You need to be very gently when trying to remove the exhaust bolts from the heads. Be prepared for some to possible snap off or strip. After all this time and the heat cycles they tend to get rust fused to the heads and not want to come out. I replaced the manifolds on my 69 and a few did break off. I was able to use a combination of heat, patience and in the end I welded a bolt to the stud to slowly turn it out. Eventually I am going to pick up an induction gun as those things are pretty sweet when trying to remove old rusted bolts and studs.