[nomis]

I have a 1975 280 that is basically stock except for a bigger throttle body, and a ported head. I was thinking of putting an aftermarket exhaust system on it. Would I gain any performance with headers and/or exhaust modifications? If so the Monza system runs around $400 for the headers and muffler. Is that a good one?

 

[yo2001]

I had better power from MSA 6 in ! I think. I've never dyno and campared

 

[zspeed]

Stick with MSA headers and exhaust, you will like their products. My 2cents.

 

[zspeed]

Oh, to answer your other question, yes you will gain a seat of the paints difference and about 15hp. Hope this helps.

 

[szlash280z78]

how much did it cost to port your head? was it worth it?

 

[nomis]

The previous owner had it ported when he blew the headgasket and the head was already off. I'm not sure how much it costs, but the car is very fast now so I'd say it's worth doing.

 

[larueb]

Don't foreget to wrap the headers before you install them.
The heat is terrible when they get lit if you don't.
Good luck!