I am going to be purchasing an exhaust system for my 67 coupe 289. I will be using stock manifolds with dual exhaust. I don't anticipate ever swapping out for headers, but may go with a 4bbl carb and a mild cam in the future. I am wondering weather I should go with 2 inch pipe, 2 1/4, or 2 1/2.

Any suggestions are appreciated. Thx.

 

2". Look to NPD, Ebay or the like for a pre-bent, aluminized system that you can bolt-in at a reasonable price.

 

+1, 2" is big enough, the bigger the pipes the more likely you are to leave part of it on a speed bump!

 

2 1/4" is all you need for that engine. If anything, the mufflers in that size will be slightly less restrictive than in 2", and I'd let that set the pipe size. I used that setup on the '66 that my daughter was driving (eventually running a stock-cammed 302, a 4-barrel of around 400 cfm, stock exhaust manifolds, and auto tranny and running on 195/70-14 tires for ride height reference). IMO, for mostly street driving you need at least a 347 before you start needing the 2.5" stuff.


Norm

 

Ihave a stockA code 289 and you will not need any pipes over 2". That is what I'm running.

 

I have 2 1/2" pipes with flow 40's. Read different articles on what size to use with all sorts of different information. I just went with what the muffler place recommended and so far so good. If anything it feels like it runs a little smoother not dragging.

edit - running off stock manifold on a 289.


http://s154.photobucket.com/albums/s...ent=Flows1.flv

 

Well, thanks guys. Gothand, I am going to be purchasing one of the aluminized kits from ebay. They are about 160. Seems like a good deal. Anyone have any experience with them?

Ndnboy, car sounds great. However, I think the flows will be a little to aggressive for my taste.

Hornblower, beautiful stang....nothing else to say.

I guess I will prob. go with the 2 1/4. Middkle of the road. Any other opinions welcome.

Thanks again guys.

 

Rules of thumb:

 

Thanks dodgestang. From your chart 2 1/4 seems about right to me.

 

2.25" will be plenty for a 289. Unless its a really hi revver, then Id go with 2.5".

I hate to say it though the chart is a little off when it comes to the single exhaust side. On the 300-350CID 250 hp it says to run 1- 3" or 2 -2.25". Well the only problem is that 1 - 3" pipe will flow MORE than 2- 2.5" pipes, so youll lose a bunch of torque if you went with exhaust that large. But hey youd gain a bunch of top end.
-P.