You don't need headers to make power. Will you (usually) make more power with headers and exhaust? Yes. Do you need the difference? In street driving, usually not. I have one of each, both are stroker 340's, 422 and 426 cubes respectively. Both are built very similarly, similar cams ported iron heads that flow at around 200, both in 71 A-body cars with manual transmissions and 3,91 gears. Both have both been dyno'd so I have real data on them. The 426 cam specs are attached, the 422 was a very similar grind. The 426 made 450hp and 500tq. These numbers were made with exhaust manifolds, stock iron intake, stock Thermoquad carb, and everything else externally stock down to the belts and hoses. Now, the 422. It has TTI headers, mandrel bent 3" exhaust, a single plane intake, a Holly 950HP carb, 7AL ignition, and all the other 10 cent tricks. It made 530hp and 520tq on the dyno.

So, bottom line, A LOT of $ and optional equipment (as a package that works well together) resulted in roughly 75hp and 20lbs of tq most things being equal if not at least similar.

On the street you simply don't need the extra hp. the 450 engine will blaze the tires at any speed and torque is so close it feels the same.

.02

OT have you dialed in the dist spot on? It makes a world of difference. Is the A/F ratio correct? mandrel bends in exhaust & general free flowing? Here's a BTT for ya since you ain't gettin any love on your Q (& I ain't a cam guy).

Thanks for those dyno numbes Scott. Where did you make peak hp on that stroker motor with manifold? I assume it was pretty low in the rpm band.
Maybe I would be further ahead putting a stroker assembly in it.

My original idea was to put headers on it but TTI's and full exhaust run close to 2k in Canada so I'm hoping for a better option.

Maybe I would be further ahead putting a stroker assembly in it.

Because that's a cheaper option than the headers and exhaust?

You don't need headers to make power. Will you (usually) make more power with headers and exhaust? Yes. Do you need the difference? In street driving, usually not. I have one of each, both are stroker 340's, 422 and 426 cubes respectively. Both are built very similarly, similar cams ported iron heads that flow at around 200, both in 71 A-body cars with manual transmissions and 3,91 gears. Both have both been dyno'd so I have real data on them. The 426 cam specs are attached, the 422 was a very similar grind. The 426 made 450hp and 500tq. These numbers were made with exhaust manifolds, stock iron intake, stock Thermoquad carb, and everything else externally stock down to the belts and hoses. Now, the 422. It has TTI headers, mandrel bent 3" exhaust, a single plane intake, a Holly 950HP carb, 7AL ignition, and all the other 10 cent tricks. It made 530hp and 520tq on the dyno.

So, bottom line, A LOT of $ and optional equipment (as a package that works well together) resulted in roughly 75hp and 20lbs of tq most things being equal if not at least similar.

On the street you simply don't need the extra hp. the 450 engine will blaze the tires at any speed and torque is so close it feels the same.

.02

DD340 those numbers with a non sure grip are pretty darn good. It would be interesting with 3.91s and tuning.

Running 13.7's with 3.23 open with that cam, and stock manifolds sound pretty well tuned already

I have been running a 69 dart 340 for a few years with a racer brown cam 220* .460 lift cam. It works really good but I would like to increase the horsepower. Any recommendations for a small block running stock manifolds? I would consider a solid cam but would prefer hydraulic. I have stock 2.02 valve heads and stock 10.5 compression.
My original idea was to put headers on it but TTI's and full exhaust run close to 2k in Canada so I'm hoping for a better option.
Opinions?