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Discussion Starter #1
My 67 lemans revamp is going well, passed inspecition, on the road, and enjoying it. Turbo 350 working well and enjoying lower 1st gear vs. 2 speed auto. Here's the next cross roads: It has 1970 350 w/Edelbrock 4bbl and intake which is obviously not erra correct, and the motor has some issue such as me figuring out it has some stripped out head threads for a couple header bolts on both sides (nice surprise!), and a mashed motor mount, and I think the rear seal has a slow oil leak. So essentially the motor has to come out. But hey it's winter right?

When I bought the car, the guy gave me the original 326 block and heads, the story was that it blew a head gasket and instead of fixing it they dropped the 350 in. Lord only knows the whole story, but it does turn freely. I am leaning toward a standard rebuild of the 326 with original exhaust manifolds (fewer leak issues) and putting the intake manifold and 4bbl I have on the 350 on the 326. According to the year 1 engine charts a 67 326 with a 4 bbl would be about 285 hp, which is about what I could get out of some of the 70 era 400s that are available around on craigslist for about $1,000, or even the 350 that's in it. I can't really spend much more than about $2,000 on this phase. So what do you guys think, I'm not as up on all the options as I should be? A) should I/can I rebuild the 326 using the 350 bolt ons for under $2K? B) should I repair the 350 and just enjoy, C) Should I buy a nice running 400, D) or other ideas. Thanks, I always appreciate discussions. Don
 

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67 Basket Case Restorer
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I would disassemble the 326 and have it inspected. If it is sound and rebuildable, I would consider doing that. You can do the upgrades you mention to the factory HO specs and even more while retaining the original appearance outside. If you will be happy with the hp output, it is always cool to see the born with engine in these old cars. If it's power you're after, go for a 400. You can't get the displacement out of the 326 to match a 400. We all know if it's power we want, "there's no replacement for displacement"....;)
 

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I agree with the above post. The 326 is a good engine, durable and under rated. I've driven and owned several in the past, and the performance can surprise you. It won't have quite the power of a similar 400 or 389, but built to stock 326 HO specs, it can be a stormer. Also, it's way more interesting (and rare) these days to see a '67 Lemans with a nice 326 in it. As a tidbit, I once drag raced my '66 Coronet with a 440, 4 speed, 3.23 posi, cam and headers against a '65 GTO with a 326, 4 speed, 3.23 posi, cam and headers. I beat the GTO by about 1 car length. The Coronet was a fast car, but that little 326 was no slouch, either!
 

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Discussion Starter #4
Thanks guys. That is what I'm thinking too. I didn't mention I had a 67 Lemans in HS with a tough little 326 and a turbo 400 with shift kit.

Do you estimate the accesories from the 70 pontiac 350 bolt onto the 326 (like water pump, alternator, power sterring, intake, exhaust, etc.)? And, what things would you make sure you did on the rebuild?

As always thanks and appreciate the advice. Once I get the rally wheels on it I'll post some pics.
 

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My 67 lemans revamp is going well, passed inspecition, on the road, and enjoying it. Turbo 350 working well and enjoying lower 1st gear vs. 2 speed auto. Here's the next cross roads: It has 1970 350 w/Edelbrock 4bbl and intake which is obviously not erra correct, and the motor has some issue such as me figuring out it has some stripped out head threads for a couple header bolts on both sides (nice surprise!), and a mashed motor mount, and I think the rear seal has a slow oil leak. So essentially the motor has to come out. But hey it's winter right?

When I bought the car, the guy gave me the original 326 block and heads, the story was that it blew a head gasket and instead of fixing it they dropped the 350 in. Lord only knows the whole story, but it does turn freely. I am leaning toward a standard rebuild of the 326 with original exhaust manifolds (fewer leak issues) and putting the intake manifold and 4bbl I have on the 350 on the 326. According to the year 1 engine charts a 67 326 with a 4 bbl would be about 285 hp, which is about what I could get out of some of the 70 era 400s that are available around on craigslist for about $1,000, or even the 350 that's in it. I can't really spend much more than about $2,000 on this phase. So what do you guys think, I'm not as up on all the options as I should be? A) should I/can I rebuild the 326 using the 350 bolt ons for under $2K? B) should I repair the 350 and just enjoy, C) Should I buy a nice running 400, D) or other ideas. Thanks, I always appreciate discussions. Don
unless your intention is to restore a numbers matching car i wouldnt waste time and money on a 326 or a 350. since all the outside dimensions are the same i would put a 400 in it.
 

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Discussion Starter #7
Where I am confused, (showing my ignorance as I'm just getting back into this) is when I look at the engine and head ID charts around. They seem to show that a 326 with #140 heads would be about 250 hp, or 350 with #17 heads = 265 hp. Many of the later 400s which seem to be most available around craigslist etc. are listed as lower compression and therefore don't show to generate that much hp. What am I missing here? Torque? Or are you guys doing something to them to get 300+ hp? Thanks.
 

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Cubic inches = horsepower, all else being equal. A comparably cammed and built 400 with '70 or earlier heads will out perform the 326. A '67 250HP 326 with 10.25 compression will outperform a '77 400 with 165 horsepower and 7.6 compression. Up the compression on the '77 400, and install a decent cam, and it will out torque and out muscle the 326. All else being equal, bigger is better. That said, it's pretty rare to see a '67 LeMans with its born-with 326 in place, and to me, a lot more interesting than "just another 400". Just my opinion. If you want to cruise, and you want to be unique, build the 326. If you want to run fast and hard, build a 389-400-421-428-455. A friend once had a tripower '65 326 Lemans and the thing screamed.
 

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I guess you need to define how later. Here are some examples of 400's with 300+ hp:


1967 400 325,335,360HP 670 2.11/1.77 72cc

1968 400 335,350,360HP 16,62 2.11/1.77 72-75cc

1969 400 330,335,350,366HP 16,62,48(MT) 2.11/1.77 72cc

1970 400 350HP(GTO) 12(MT) 2.11/1.77 72cc

1971 400 300HP 96 2.11/1.77 96cc

Afetr '71 performance started to drop like a rock.... '70 was pretty much the peak year for performance...
 

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the horsepower #s you see are supposed to be peak power. if you arent racing, then more than likely lower rpm torque gives you more seat of the pants feel and tire smoking ability. if your engine makes 300hp at 5000 rpms but you only rev it that high ocasionally, and only for a couple of seconds at a time what is the point. torque rules! i dont know the #s by heart but i think the late model engines still have loads of torque.
 

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Discussion Starter #11
I see. And thanks, it is much appreciated. My desire would be more of the "seat of the pants feel/ tire smoking ability" and something that just runs well (pump gas). I don't envision racing anyone, except maybe to the bathroom after a few beers. One local option is a 1972 400 with 7k3 heads mild cam and HEI for about $1000. Is that a good option?
 

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I have a 66 lemans as you can see in my sig, Finished rebuilding it over 20 yrs ago and put in a 70 455,the last yr for the 10.5 to 1 compression. Also removed the vinal top. If I were to do it again I would have kept it original including the 326 2 speed, would be worth more in original condition, Though I do love the brute force it now has. still have the original engine and hood and could put it back to original except for the vinal roof.
But in my opinion go with the 326 4bl and turbo 400. it will be more economical and there fore more enjoyable to drive.
 

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I see. And thanks, it is much appreciated. My desire would be more of the "seat of the pants feel/ tire smoking ability" and something that just runs well (pump gas). I don't envision racing anyone, except maybe to the bathroom after a few beers. One local option is a 1972 400 with 7k3 heads mild cam and HEI for about $1000. Is that a good option?
Not bad... HEI ign and the cam will help it out too...

1972 400 250HP 7k3 2.11/1.77 96cc


(I love stats).......
 

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If the '72 400 is a runner for a thousand bucks, you can't beat it. You'll spend three times that rebuilding your current combo. That said, heed what TORRED 1 is saying. He's been there done that.
 

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Discussion Starter #15
Thanks again, I appreciate the perspective. I can see two equally valid camps emerging and I guess it depends on the objective.

For something different, what would you think about stroking the 326? It would still be original, if your going to replace the crank shaft anyway, it doesn't add that much $$ and the rest is about the same for cost. I think .30 over and an extra .5 inch of stroke would make it about a 370 cu.in. or so.
 

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the 326 is already way under square i think. long stroke small bore. i dont know how far you can bore safely but i think it woud benefit most from more bore.
 

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I agree with 66TempestGT. The reason OHV V8's were so much stronger and better than the flathead V8s that preceded them was due to their "oversquare" design. Bore diameter was equal to or greater than the length of the stroke, which made for a more efficient combustion chamber and much lower piston inertia/drag. So, more power and higher RPM were available, and much less piston strain and crank strain. Now, for torque, the old engines had long, long strokes and a small bore. they were undersquare. Not much HP, but a lot of torque. My straight 8 1937 Chrysler made 110 horespower out of 273 Cubic inches, but it had over 250 foot pounds of torque....at something like 1800 RPM! Great for a tractor, but not so usable on the street. It would pull away from the curb in top gear at 500 rpm without a wimper, but top end was under 90mph. It was all done by 75. I think a stroked 326 would be a lost cause. You'd be losing the rev-ability and responsiveness of that engine, and turn it into a slow revving, small bored, expensive project. You might contact Butler Performance. They may have some info. If you are considering a stroker 326, though, I'd bag the engine in cosmoline and stick a 400 in the car. You'll be much better off.
 
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