After weighing my options, and reading that a #'s matching car is worth up to $10,000 more than non-matching, I have decided to rebuild my 326. Does anyone have any proven combo's that will give some good HP? Does anyone know the difference between the 140 & 141 heads, one website says that the valves are 1.94/1.66 and the base 326 has 62cc (9.2:1 compression ratio), and the high output has 52cc (10.5:1 compression ratio), and another website says that the valves are 2.11/1.77 and has 72cc for both the 326 base and 326 H.O.?? I don't know if I should rebuild my existing heads (#140), or get new ones (I can get #62 heads that are already rebuilt for $400- they are also suppost to be 2.11/1.77 valves and 72cc). I put Flowmaster dual exhaust, and it has a Edelbrock 600cfm carb.

Here's another thought. Your numbers matching engine is only valuable if it's not damaged. Grease it up, stash it away, build a 400. More power, no more money.

I agree with Vikki, and usually it is more power for LESS money than building a 326 or 350!!!!!

Once I have the money together I'm going to have my 326 rebuilt. To it's kind like a piece of history to me, last year of the motor, first year of the Firebird.

Agree as well...

I just don't want to have to 'find' a spot in my garage for the engine to sit. Come winter, my wife is going to want to park her van in the garage (I already sacrificed 'my' parking spot for the firebird). Don't get me wrong, I REALLY want to put a 400 engine in it, I already looked at one that a local guy has, but it needs to be rebuilt too. I figure if I could get 350-400 HP out of the 326, that would be good for me. I don't plan on driving it very often (not a daily driver), so the 326 is probably OK....Man, I want that 400 engine..you guys are making me think. I'm going to look at my garage to see if I can store the 326 somewhere, unless someone has a good upgrade combo that I can use. I read in the faq section, that someone got 570 dynoed HP from their 326 (but they did't list part numbers), https://firstgenfirebird.org/FAQ/engine/general.html - about 11 'pages' down "Engine Rebuild (Revisited)"
that is definitely enough power for me (I don't think my current suspension could handle that much).

Financing 570 HP from a 326 would probably not be the wisest choice for your budget. The same money invested in a 400 (or better yet, a 455) will give you far more driving pleasure. Horsepower doesn't move a car ... it's torque that does all the work.

You don't really need to find a spot for the engine. You need only store the long block - with the intake. Everything else on the motor will bolt up to the 400. (The intake will, too, but you probably would rather have a factory or aftermarket manifold that takes a Q-Jet.)

Motors can be stored with the flywheel side down by installing stem casters into the bell housing holes. I use coupling nuts over the stem to give the caster more rigidity. This keeps the long block mobile and takes less floor space than an engine stand or an engine on a furniture dolly.

I don't want 570 HP, my suspension can't handle it, and it would cost too much to upgrade (the torque on that engine was 576). I am also considering resale; I think that someone would rather buy a car that has the original engine in it, than have to put it in....not that I intend on selling the car, but the way the economy is, you never know what is going to happen from day to day. The 400 engine that I was looking at needed most of the 'bulky' parts from my engine anyway (alternator, steering pump, pulley setup), so the 326 would take up less room, I just don't know if I want an engine laying around. If I lived in LA, I wouldn't have a problem having the extra engine, my wife could park her car in the driveway.

I don't think anyone is clamoring for a 326 2bbl. I think the resale value is only compromised if the car was originaly a 400, an HO, or a Sprint. Just my opinion. When I bought my 1969, I knew it had a 1968 350. I didn't care because I knew I wasn't going to leave it as-is. I wouldn't have paid any more for the correct 350 2bbl.

I'm clamoring! Just kidding but you don't really see that many around since everyone pulls them for a 400, I like to be different. I bought mine for the color but, if it was a matching ohc 6 or 400, I would have keep it as close to original as possible.... with a rear spoiler. If I want to go fast I just jump on one of my bikes, it take a lot of money to make an old bird do a high 10 second 1/4 mile. Bikes aren't for everyone though and Canada doesn't have much of a riding season. It's your car. Do you still have the original intake and 2 barrel carb? When was the build date of your car?

i agree , seems like everyone wants a 400 c.i. engine bird . and if swaping an orignal overhead cam 6,326, 350 out for a 400 to me it is a loss of history of that car. i have a 350 , 2bbl numbers matching 69 bird . i could not see changing the engine in my car for a different engine . its a 40 year old car , i know some of the history of it. i fell like i would be taking away from it to make big changes in it. i look at it...their are plenty of birds custom, modified, altered ect. and they are nice birds. but there is only a handful of orignal , and restored birds. its nice to see a 326 bird spreading its feathers.

For the most part I agree with all the comments...

A basic rebuild of your 326 vs a 400 or 455 build will probably cost more and you'll end up with a nice 250+ HP diver. If you are able to source a set of 141 heads you might be able to squeeze out 300 HP.

Muscle Car TV built up a 326 for a LeMans a couple of years ago. It was stroked to 376 inch and reused the 140 heads (could not find 141's). Not sure if it was dynoed, but it looked like it made good power. Still a lot of work and $ to make maybe 320 to 350 HP.

RossettiJ is right, nobody is clamoring for a 326 car. You wont loose anything with a 400 under the hood. That's what folks want and that's why original 326 cars are becoming even more scarce.

If it is important to you to keep it original then rebuild the 326. But regardless of what you decide, it is your car, so build it how you want it.

Personally I love my 326, but I'm a bit of a purest. It is what it is and it's only original once.

very well put.

I would like to know if anyone knows the difference between the 140 & 141 heads, different websites say different things. The 326 was suppost to have 250 HP, and the 326 HO was suppost to have 285 HP; the HO had a 4 barrel carb, dual exhaust, and different heads. I now have a 4 barrel carb, dual exhaust, and headers. I must be close to the HO rating. I am thinking of changing the cam, and rebuilding the heads.
I don't think that I will 'mind' the 326, I just wish it was a bit faster (stock). I had a Nissan Altima 3.5SE, 5 speed manual that was suppost to do 0-60 in 5.9s, and 1/4 mile in 14.4s; I would hate to get smoked by someone in an Altima, I guess I just have to accept the car for what it is. I think that the Altima would smoke a lot of the 400 cars too.

Put a steeper gear in the back & it will have more get up & go. You lose mileage in the process. I'd put a 3.36 or 3.55 gear in it.


Steve

Just to throw in my 1.5 cents... After completing my '67 326-2 resto, I was a bit disapointed by the lack of power. I had been driving my '68 400 for a few years, and switching to the 326 was surprising. The 2 speed powerglide is also a bit lacking, but then I decided to keep in mind that 40 odd years ago these cars were borderline state of the art. And all of the waves and thumbs up made me realize that they are both amazing cars. I don't think I would change anything. If power is what you are after, I'd go to the 400 as well and tuck your 326 aside in a safe place.

I have a 326 in my 67. It is the original motor for the car so I wanted to keep it. I had it bored .030 over and put a 068 cam in along with the usual 3 angle valve job etc. I found an original 4 barrel manifold and used a carter afb carb. I gasket matched the intake and exhaust ports and just used the stock log manifolds after deburing and matching them to the gaskets. That was almost 20yrs. ago and she still runs great. If I didn't have the original motor though I would go for the 400.

Compression. Valve size is the same for both (1.92/1.64). I also believe the cam is the same spec too.

Could you then mill the 140 heads to get the smaller chambers and higher compression?

It will cost you the same to rebuild the 326 with HO heads than a 400.

Buy a good 400 core with as much bracketry and as complete as possible, most from your 326 will work.

The replacement pistons available for a 326 are usually cast and not forged unless you have custom Diamond or Ross made. If you rebuild, get a complete kit from Summitt or Jegs instead of piecing it together.

I used to rebuild Pontiacs at a shop, so IMHO, I say go the 400 route. I can help locate a core for you as I am 15 minutes from Windsor and have many sources.

You could, but the cost to mill negates the benefit. Cheaper to find a set of #141 or #18 HO heads. You would be milling 50 thousandths off the deck and may have to mill some off the intake for geometry.

I have a complete '67 400 engine that would be a great rebuilder core. I have a TH400 core too. Both came out of a running car but I wouldn't drop them straight back in.