Ok, I am in need of some insight on how others have bumped up the power of their 326 engine. I currently have a 326 H.O. block and heads with the correct AFB carb and intake. I would love to push around 350 H.P. out of it.

Any suggestions or ideas?

Thanks

Very good question...I would suggest some changes with regards to the camshaft. If fact, I know someone who has the perfect camshaft for this engine...

I think I heard you were the right one to talk to about the cam. We will be in touch.

350 HP from a 326 is a tall order! A "high" rev range will be needed. Porting and a "big" cam will be required. Larger valves can probably help some, but not the "standard fare" for the Pontiac, since the bore size is too small for the 2.11 intake valve to "work" properly. The 1.96" intake valve is probably the best.

The connecting rods need to be replaced. The original cast rods weren't "good" when new, and are now over 40 years old. For a little more than the cost of resizing the stock ones with new bolts, you can have forged rods.

326 is a "small bore/long stroke" design. Trying to make it perform like a 327 is basically futile. Real "torquey", though.

If you wanna get "silly", I can outline a good build stategy. Not gonna be "cheap", though.

Jim

The 350 H.O.'s made 320 hp from the factory.
But also had a q-jet carb n intake.
350 shouldnt be a prob to achieve.

Talk to Bruck Fulper at Rock and Roll Engineering...He will get you 400 horses out of a 326.









*snicker*

The original rating of the 326 HO was a SAE Gross HP rating. I believe that rating is about 15 to 20% higher than today's SAE Net ratings. So getting 350 SAE Net HP is going to be difficult, but not impossible. Just expensive!

Thanks all for your responses. It sounds like it can be done, just going to be a bit painful on the wallet. I have went struggled with the expense of building this engine over a 400, but the rarity of it is what prompts me to continue on. How many 326 H.O. 4 speed convertibles have you seen?

Honestly, unless you are a speed demon. 300hp is plenty for a cruiser. My cruiser has roughly that and has no problem getting up on the road. Why are you needing 350hp? What is special about that number? Build the motor to enjoy not for speed. Ask Earlybird he has a 326 in his lemans. Sure he would like more power but he has bragged how a good intake, 4 barrel, duals, long branches will help bring any stock motor to life.

Im my opinion and somewhat an expert on the value and rarity of these cars, and have built Pontiac motors...

What you state above is a perfect reason to pull the motor, store it, replace with a 350/400 and NOT try to modify and increase HP. You will loose approximately 40% of that cars value if you modify, port, rebuild, and God forbid, grenade that motor. You only have one engine block correct for that chassis...why devalue the car with an overpriced engine rebuild with marginal result.

The second part of my initial comment...it will cost you less (yes less) to rebuild a 400 than a 326. Your off the shelf pistons for a 326 will be cast...so you will need forged pieces custom made to handle your wishes. You can get Speed Pro/TRW off the shelf for a 400 for $250 less. For the price of a 326 build, you can get a complete 400 (or 350 HO) for $700, have it rebuilt, and you will come out relatively equal as far as cost comparison.

If you were doing a stock rebuild, I wouldn't have commented, but you answered your own question that I quoted above. Unless you have money to burn, why potentiate possible devaluation with your rare car?

I wouldn't...but thats me.

I totally agee with jose67. No matter what, you're never going to be the fastest car on the road but you can easily be the coolest and the more you go into the non stock zone the more time and energy(and money) you're in for. Build it safe and comfortable and it will be a great car for years to come.