[66temp]

I am new to the Pontiac world. I was lucky enough to come across a 66 tempest w/ a 326 2bbl with a powerglide? 2 speed. I had the engine tuned and wet/dry compression done. Mechanic says it a solid motor. now to the question.
I need more power. I realize the 326 is not the best motor to build. But since it doesn't need a rebuild I would like add. I was thinking 4bbl, headers, and dual exhaust. I also have a msd5 in the garage. I need to do these mod little at a time. What should I do and in what order. and with the carb should I use stock intake from another car or buy edelbrock or something.

Thank you in advance.

[66temp]

I am new to the Pontiac world. I was lucky enough to come across a 66 tempest w/ a 326 2bbl with a powerglide? 2 speed. I had the engine tuned and wet/dry compression done. Mechanic says it a solid motor. now to the question.
I need more power. I realize the 326 is not the best motor to build. But since it doesn't need a rebuild I would like add. I was thinking 4bbl, headers, and dual exhaust. I also have a msd5 in the garage. I need to do these mod little at a time. What should I do and in what order. and with the carb should I use stock intake from another car or buy edelbrock or something.

Thank you in advance.

[Half-Inch Stud]

4Bll intake and Q-Jet. Factory Iron 4BBL intake wil be a super choice on the 326.

May as well install new lifters while the Intake is off. Chances are the present lifters are dished.

HEI distributor.

Can leave the exhaust alone.

get some rear gear.

[66temp]

SHould I check junk yards? Which cars or engines. I read in my owners manual about a 326 H.O. what's the story on that. Can I convert my 326 to one?

[mike nixon]

personally i'd throw a set of headers and dual exhaust on it while i was there. mike

[carbking]

Even though the 326 is a solid motor, it might be more cost effective to drop in a stock 400 and transmission from a 1969 or so. Weighing your options before you start saves you money in the end.

[Will]

The nice thing about Pontiac engines is any bolt-ons you buy for that 326 will also bolt onto any larger Pontiac engine in the future.

The factory 4bbl/Q-jet intake is the way to go (and cheapest). After that, small-tube headers (1-5/8") and dual exhaust. Then get the distributor recurved. Those changes alone ought to ad some pep to that little engine.

A cam swap wouldn't hurt either, but stay on the conservative side. You want something that will build torque in the low RPM range since that engine really can't breathe in the upper RPMs and the car probably has tall rear gears. I don't normally recommend the Comp High Energy series cams, but in this case, something like the Comp 252HE would be just the ticket. The smaller of the Comp Dual-Energy line would also be a good choice, or one of the small XE series cams like maybe the XE250.

Oh, one other idea: Swap that 2-speed tranny for a TH350 with a 2100 stall ASAP. That will make a huge difference to how the car feels.

Good luck!
-Will

[TCSGTO]

The 326 isn't a bad motor at all and if you stay conservative with the cam and carb it may surprise you. Like someone else posted lose the 2speed trans and get a T350. It's a bolt in swap and you can even use your old torque convertor. It fits right in and is looser than a stock T350 unit. A gear change would really help too. 3.23 to 3.90 depending on how much freeway driving you do.I saw a stock 67Tempest 326HO with cast intake/exhaust,Carter AFB,4 speed run mid 14's at Norwalk a few years ago on redlines and I believe 3.90 gears. Good luck and have fun!

[66temp]

What is the difference between a 326 and a 326 H.O. compression? carb? heads?

[TCSGTO]

The 66 326HO had 10.5to1 compression compared to 9.2to1 for the 2 barrel. It used the 500cfm Carter AFB,had dual exhaust and ran the same cam as the 2 barrel motor. It was rated at 285HP, the 2bbl 250HP. They aren't high reving motors since it is a long stroke small bore design. The Q-jet intake and carb are easier to find and probably would work better. A small aftermarket cam would be a good addition. Headers and duals too. Don't worry about raising the compression as 9+to1 is good enough and will let you run pump gas. These mods and parts will work on a larger motor too should you deside to upgrade in the future.

[Dennis B]

We just did my sons 326 a couple years ago. We had the 250 hp and made these changes. Bored it .030" over. Replaced the cam with a Crane max Velocity hyd cam #283941 Replaced the 4 sp with a TH 400 used an Edlebrock rpm manifold and a 600cfm Edlebrock carb. We went from a 3.23 axel ratio to a 3.90 posi and instralled Hooker supercomp headers through 2 1/2" pipe back to the rear axels, and the thing runs great. Just a little lump at idle of about 700 rpm and good response with the 3.90 gears. Headers help, but, if I did it again I would get the factory HO manifolds. These headers fit good but as with all headers they are a pain in the a##