[67 pajaro de fuego]

I have a 67 Firebird with a 326 engine. I have most of the guts to upgrade the heads; roller rockers, hardened pushrods, valve guides, etc (I don't have a cam yet). I would like to upgrade the performance as much as possible. Is it possible to put 350 heads (or something else) on the 326 to increase torque &/or horsepower? How do I know what heads the parts I have will work with? Thanks a bunch!!
Mike

[bullheimer]

i have a 326 also. as far as i know, no other heads will fit, due to water jacket issues, even tho they will bolt on. the 326's bore is 3.72 and the 3.50's bore is 3.875. 400's bore is 4.12 and i know for sure that 400 heads will NOT bolt onto a 326, nor i THINK, a 350. stroked out 350's in the 383 range have started to make, because of the new cranks, stupid HP comparable to a 400, but i am pretty sure there is nothing for the 326. all the head parts are interchangeable tho. and you can put in camshafts and all rods are the same, as well as external stuff all fits, except RA IV round port headers, and 65 and later intakes won't bolt onto pre 65 heads. i put a summit 2800 cam in my 326 with a 4bbl intake and Q jet. i can not feel any noticable difference!!! however, i don't have headers or port work and have high gears. i like the 18mpg tho! on cheap-o gas even. what has made the biggest difference so far has been dumping the 2speed trans for a 3 speed. it cut 2 full seconds off my slow quarter mile time, and i am still a very slow 17 seconds. as my car is so clean and low miles, i have been considering leaving it stock, well, as is. i kept all the parts. i would never ever run that 2sp again. my car runs like brand new. i put a qjet on from an olds 350 i got at the wrecker and had a local yokal rebuild it. i bought a 455 and have a 400 for other projects. the 455 was to go in my tempest, but it is so spendy to build a motor, i don't have any money. i will keep the 455, but the 400 may go into a 67 lemans i have, or i may sell the car and engine together, i don't know yet. my temp is a 66. good luck with the 326. they made two sets of heads tho. a 4bbl 326 in a firebird had 4bbl heads. mine are 2bbl heads. it can be you will like 4bbl heads better if you have the 2bbl heads, i havent seen any, but if you port them they should run great. and btw, all pontiac heads except the raiv HAVE TO BE PORTED to run worth a crap. they are an extremely restrictive head, exp the 4x and 6x smog heads. edelbrock heads will NOT fit a 326 either.

[67 pajaro de fuego]

Thanks for the information!! I guess now I don't have to worry about swapping out heads. How do I tell if I have 2bbl or 4 bbl heads, and what does "bbl" stand for?

What transmission did you go with?

thanks a ton,
mike