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Hey, so I have a 326 but the tri power intake I’m looking at says it will fit a 389 ci. And I’m curious if it would fit my 326 as well from what I know it’s an original intake from a 60s Pontiac
 

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Pontiac heads/intake pattern are all the same from 1965 and up. If you have an earlier tri-power, 1964 and earlier, it will not fit.
 

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That's not possible to answer without details and desires from you. I'm partial to the tripower, but that doesn't mean it's right for you.
 

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That's not possible to answer without details and desires from you. I'm partial to the tripower, but that doesn't mean it's right for you.
I’ve got a 1966 Pontiac tempest with a completely stock 326 in it and I believe the intake is off of a 1965 gto with a 389 in it.
 

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Based on my own experience with the stock 326, it will fit and will look great with the tripower but will not have much more power. It might even run worse. Mine just didn't beathe well and never seemed to make much torque. It was a great cruising motor, but not the hot rod motor I was wishing I had. Pontiac had their reasons for not using the 326 in the GTO. It could still be fun to have, but don't plan on winning many races at the strip.
 

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At the end of the day, for most folks a single 4 bbl is easier to tune and maintain than any multicarb setup. That being said, IMHO Pontiac=Tripower, so it's hard to vote against it.
 

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You can go for just the look. Block off the end carbs with block-off plates and simply run on the center carb. You can easily hook up linkages and even fuel lines (plugged) to give the underhood that tri-power "wow" factor. Hooking up all carbs will be way too much for the 326CI, but it has potential if later down the road you wanted to keep the engine and transform it into the 326HO version of the engine.

My 1957 347CI with dual quads...........the front carb had a block-off plate and linkage was hooked up to psych out the locals. LOL

03 1957 Pontiac 2-Dr Sedan - ran on 1 carb only.JPG
 

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Discussion Starter #12
Thanks for all the responses and help. I’ve been thinking about doing an ls swap so maybe I’ll just save the cash and stick with that.
 

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Thanks for all the responses and help. I’ve been thinking about doing an ls swap so maybe I’ll just save the cash and stick with that.
I'm more old school so I'm not a fan of the LS swap. I think Butler and others make a stroker kit for the 326 which is what I would do if I still had one. I think they can be rebuilt to have much more torque than factory set up. That way you keep the old school look, make use of your tripower, and keep the 326 emblems on the fenders!
 

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I'm more old school so I'm not a fan of the LS swap. I think Butler and others make a stroker kit for the 326 which is what I would do if I still had one. I think they can be rebuilt to have much more torque than factory set up. That way you keep the old school look, make use of your tripower, and keep the 326 emblems on the fenders!
I didn’t realize that I’ll have to keep that in mind! It would be nice to keep the original engine in it
 

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You can go for just the look. Block off the end carbs with block-off plates and simply run on the center carb. You can easily hook up linkages and even fuel lines (plugged) to give the underhood that tri-power "wow" factor. Hooking up all carbs will be way too much for the 326CI, but it has potential if later down the road you wanted to keep the engine and transform it into the 326HO version of the engine.

My 1957 347CI with dual quads...........the front carb had a block-off plate and linkage was hooked up to psych out the locals. LOL

View attachment 136324
what would I need to do to make it the HO edition?
 

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The HO basically had the 4 Bbl and dual exhaust and was rated at 280HP.


But, go the stroker route and typical add-on build stiff and you can get a fairly stout engine. Take a look at the time marker at 7:15 when they put this 326 on the dyno and see what it cranks out.

 

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The HO basically had the 4 Bbl and dual exhaust and was rated at 280HP.


But, go the stroker route and typical add-on build stiff and you can get a fairly stout engine. Take a look at the time marker at 7:15 when they put this 326 on the dyno and see what it cranks out.

what would I need to do to make it the HO edition?
That's a nice video. Thank you Jim. I have not seen that one before. It makes me wish I still had my 326! That dual quad intake they used for the dyno testing is exactly what I am running on my Butler stroker engine. I have a tri-power manifold but I got such a good deal on the dual quad set up that it was by far the less expensive option for me. Still, the tri-power looks original and is more impressive with the three air filters.

Sam, I suggest you talk to the people at Butler about what you would like to do. They have been very helpful with me reaching my goals. They will also be upfront with you about costs. Either way, LS or rebuild the 326, you would be looking at money spent. A friend of mine is also talking with Len Williams in Oklahoma. He is supposed to be very good with pontiac rebuilds as well but I do not know if he carries as many parts as Butler. Either way, parts can be ordered and you could even build the motor yourself if you feel comfortable doing so. I just love the idea of everything looking all original Pontiac under the hood, yet it has even more power than when new.
 

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Discussion Starter #18
The HO basically had the 4 Bbl and dual exhaust and was rated at 280HP.


But, go the stroker route and typical add-on build stiff and you can get a fairly stout engine. Take a look at the time marker at 7:15 when they put this 326 on the dyno and see what it cranks out.

thanks a lot for this information. If I was to cam it on top of the dual exhaust and 4 barrel do you have any idea of how much HP I’d be making?
 

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I can't give you a number but I tried the same thing and even added four tube headers to that combination but the heads were just not designed to flow very well. I'm not sure what all Butler did to those 326 heads in that video but that was probably the second most important change after the stroker crank. If you have a local machine shop that you trust, you may want to ask about porting the heads and a multiangle valve job. It can start to cost a bit of money very quickly, but I suspect you will be disappointed in your investment of time and money with cam, intake, and exhaust if you don't address at least the heads.
 

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thanks a lot for this information. If I was to cam it on top of the dual exhaust and 4 barrel do you have any idea of how much HP I’d be making?
You will get a lot of pro's and con's on building the 326. Most will suggest just stepping right up to a 400 and going with a stroker kit to get good HP. The LS is another argument as it certainly has its merits, but, it is not a Pontiac.

That said, keeping the 326 means less conversion pieces or modifications to make things work. What kind of HP? My guess is that you have the 250HP engine with the #094 heads. The engine has 9.2 compression which is perfect for pump gas. The 285HP engine for 1966 used the #095 heads which would have had a smaller combustion chamber and had 10.5 compression - not pump gas friendly, but needs higher race gas blend or octane additive to run.

So if you just left the engine as is and did not do a rebuild, and added a cam/lifters, headers, tri-power, and dialed in your timing curve, You might see the higher 285HP, but pump gas friendly. Keep in mind that a Pontiac makes torque and that is what you want over HP.

If a rebuild is in the picture, then TQ & HP will go up depending on how radical you want the engine to be - just as seen in the video. You have to match all your parts in the engine, then match your engine to your transmission and rear-end gearing.

Both heads have the same 1.92"/1.66" valves. As mentioned, you want to improve the heads.
You have to take into consideration the smaller bore, so size of the valve and total valve lift won't be the same as for a 389, 400, etc. because a larger intake valved head will hit the side of the cylinder walls. But, you should be able to go to a larger 2.02" valve. This will help head flow. Leave the exhaust valves as is. But, you want to also have a 3-angle valve job, gasket match the intake entry on the heads to an intake gasket, and clean-up/smooth the runners - nothing fancy here, just a basic job. Your machine shop should also install bronze valve guides and I would add Viton valve seals which will require the valve guides to be machined smaller so they can be used.

You will want new stainless steel valves and new valve springs to match your cam selection.

The heads might run between $800-$1,200 depending on your shop and how "complete" the rebuild of them is. You have press-in studs and high performance heads use screw-in studs which can be added, but will increase your costs. The press-in studs are fine, but limit you to less lift, but with the 326CI, a cam that would be "mild" in a 389/400CI will be much more radical. So you can keep lift reasonable, under .450" if going aftermarket on the cam from what others have said with press-in studs, and use a good duration cam with something around 112 LSA. If you went with a factory cam, I think the "067" would be the most. The "068" would probably be too radical for the 326.

I would get a cam recommendation form whomever you select whether you just use the engine as is or decide to rebuild it. If the engine seems to run well and doesn't smoke/burn oil/leaks oil, I might just opt for now the upgrades you listed and see how you like them. If you decided to do the rebuild, you may want to swap out to a more radical cam which is not a big expense with regards to a hydraulic flat tappet cam, and would still keep the tri-power/headers.

One thing also to consider is piston replacement. The 326 piston can be hard to get, but Egge has a cast piston and you can click on the right side for overbores:
Egge Pontiac Piston Set

And of course Butler can have Ross make a set of custom forged pistons which will be more expense. Cast will be like factory and as long as you don't go crazy with RPM's they would be fine.

Ebay seems to have an inexpensive rebuild kit that offers pistons. Never used this vendor, but the parts shown are quality names.

 
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