I currently have a 69 camaro with the specs listed in my signiture, and i average about 12-14 mpg. My question is, Im considering adding dynomax headers, trickflow 23* heads and a 268H cam, what change in mileage could I expect from this? I don't know if I can afford to drive this thing..

I wouldn't look for a mileage improvement at all; will sound better, though :D

Get rid of the A/C and stereo stuff - its just dead weight ;) - should be worth 1 MPG

Interesting though, without the supercharger, my engine makes 310 RWHP. With the supercharger, on the highway, with the old Muncie, and with 3.73s, my car would average 13-14 MPG. So more performance parts won't get you more mileage. However, that is a GREAT excuse to use with the wife.

My stock 350 with only a 350hp/327 cam got like right at 16/16.5 if I kept my foot out of it.

I used the same carb. and intake on my junk 301 with an -097 solid cam and it got about the same, again if I kept my foot out of it!

My 406 with a 280/230 cam and Hooker headers got like right at 15 on the road running at that time 55 to 60 mph b/c of the 55 speed limit. This was with 26.5" tall great big old fashioned L-60's...

My car has an M-20, 3.31's and tire sizes that varied from stock at like 25.3"/25.5" all the way up to 29" or so when I had the real tall, skinny, Firestone Town and Country 9.50 M&S tires on her.

Hope this helps... pdq67

Yeah ,I tried that a few times with the wife,but shes gotten savy too me after 20 years of hotrods,but a 700r4 will really help you out

Fuel economy and performance come from an engine that is more efficient. I've found proper gearing and torque in the right place seem to be the best way to get the most mileage. Of course the first time you put your foot into it the mileage is shot... Choose your parts wisely and you can improve both.

There are a couple guys that stop in here that pull down impressive times in the 1/4 mile and can see 18-20 mpg on the drive home. I don't have time slips on this engine but have seen 23 mpg out of my 383 on the hwy at 60-65 mph in overdrive.