351C 4V with manifolds

[wrobinson]

How bad would it kill the power if I left the exhaust manifolds and married them to a Pypes mandrel bent 2.5" exhaust? I know it will make a lot more power with headers. I am planning an AOD install so I've been told it will be shorties or manifolds. I am thinking manifolds first and then later install some Sandersons shorties. The engine will be around 9.7:1 static compression with D0AE-N quench heads. The camshaft is a hydraulic roller that specs 224/230 @ .050, 569/578 lift with 1.73 rockers, and 110 lobe separation. I plan on TBI style aftermarket fuel injection on a Performer RPM intake manifold. Does anyone have experience with long tube headers and AOD installation behind a 4V Cleveland? I would like the header installation to be an upgrade my son can make later and feel the increase in power.

 

[73pony]

Long tube headers fit perfectly fine with the AOD. I believe Mr 4x4 has them with an AOD.

 

[kcmash]

I am no expert, but I would challenge the statement that headers will make a lot more power.  Noise, yes, power, why?   The original 4V and Boss 351 exhaust manifolds were HUGE!  

Just a question.....

kcmash

 

[73pony]

The exhaust ports were huge yes but the stock manifolds were fairly restrictive. A good set of long tube headers would make a considerable difference over stock manifolds with his set up and the cam he has.

 

[Don C]

Headers provide scavenging and anti-reversion that the manifolds don't. Long tube headers also boost low-end torque.

 

[wrobinson]

Ok, so what long tube header fits the best for AOD backed 4V Cleveland? I do not have a problem with headers as long as they fit correctly.

 

[73pony]

I would go with FPA's or Headmans. The Hooker's fit but then tend to turn in slightly at the collector causing them to be a little close to the trans which may cause heat transfer issues. I am not familiar enough with the patriot headers to know if they turn in or not. Keep in mind the hookers still fit and clear everything just a little close to the trans for my liking.