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Discussion Starter #1
I'm considering building a high rpm race motor out of this nice old small journal 1967 327 . I've got some ideas that I'll lay out here and I'd like some good solid constructive advice/ criticism from guys that are more knowledgable than myself. I'll lay out what my idea is below and then whoever wants to....go ahead and let me hear it / have it lol
I'm currently building a 385 torky for street use that wont see more than about quarter after 6 that's gonna go in my 66 chevelle this spring .
But on with the 327 plan/idea .
This piece of history has been layin on the floor since 03 when I traded an 83 350 882 headed mexican block s h itster for it lol
It's been begging me ever since .
Im thinking maybe build this thing to twist 8300 rpm max 450 to 500 power at about 8 grand with a very long duration high lift cam and run a 456 gear with a stout th350. 13 to 1 or more CR
First off I'm thinking I need to build as much torque as I can because of the smaller inches.
How to do that is the big question along with the small cubes lol
So now I dont think I can put a 350 crank in this block seeing as it's small journal but correct me if I'm wrong .
I'm going to assume for the moment that I cant . So if that's the case I guess I'd be better to use the 327 crank that's in the block now for more torque versus putting a 283 crank in it and destroke it to a 302 . If I did the latter I could spin it to the moon but is there a way I can get more torque that way ??
Longer rods ?? Idk .
OR might I be better off with the 327 crank ?? And if that's the case the question of building torque still begs .
And how much can I would I should I bore this block given the stated goal ?
Then for up top maybe a small cc runner head ?? 180cc or less ??
Then I thought I'd run a true dual plane without a cut out in the divider with quite a bit of carb on top and maybe an anular booster. The smaller heads and the dual plane intake ought to help out with the torque I'm thinking but again I'm wide open for any suggestions or critique. I'll take anything you got other than " start with bigger inches "
Because this is what I got and it's a 67 and it's cool and I want to build it and thats my story and I'm stickin to it lol
 

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The 327 wasn't a torque monster. If I already had it and wanted to build it I would forget about trying to build more torque and concentrate on building the best overall combination. A lot of what you can do is going to depend on stuff like piston design and such. My first build was a small journal 327 with a small solid roller and the best set of 291 camel hump heads I could piece together. They did have 2.02 valves and screw in studs and a little crude port work. I was limited in cam size because it was a flat top engine and piston to valve clearance became a issue. Yes, it would spin to the moon but I found out at a race track tuning that it would run faster if I would shift it sooner because of my lack of head and camshaft. There is no way I'd destroke it unless it was a just for fun engine and performance wasn't a issue. My engine was .060 over and I ran it for a few years before trading it in for a 355. The 355 was superior in every way and out performed it in every way. The 327 was about a 10.5 to 11.1 engine and the 355 was a 12.5 engine. The 355 had more camshaft because of piston design. My dad was a basketball coach and he told me one time something that has always stuck with me. He said a good big one will whip a good small one. Now, he was talking about basketball players but I've found it to be true in engines also. Yes, you can make the little engine perform but a bigger engine with the same parts is going to be better. If I were going to build the 327 I'd pay attention to my machine work and make sure it was well balanced. I'd run some form of roller camshaft in it and I'd put as good of head on it as I could. I wouldn't go with big monster flow numbers. Probably something along the lines of a AFR in the 180 range. I'd try to make peak power under 7,000rpm. No need spinning a engine up just to hear it and just because it can. I would run a good single plane intake. You can go as mild or wild as you want but a few I've ran over the years include a GM Bow Tie, a old original Torker and Holley Strip Dominator.

As a added note. If you really wanted to build a good small block delve into a good set of 18 degree heads or better. The head design on first gen engines leave a lot to be desired. Why do you think the LS platform builds power like it does. It's all in head design and valve angle. I always wanted to build a good 377 with a set of 18 degree heads. At the time my little 355 was running ten teens in my 72 Nova. I had put a better piston and a good set of 220 AFR heads on it but I know the 377 would have run circles around it.
 

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I’m always in favor of doing something different, so if you want to build it then do it. But I agree don’t get hung up on torque numbers. Pick an rpm range you want, and build it for that. I think shifting it at 7500 isn’t bad. Beyond that valve train parts can get real expensive. I also agree that at that rpm it’s got to breathe well, so it’s going to be a toss up of good flow, but also maintaining velocity.
 

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350 - 327 = 23. That's a 6.6% decrease in cubic inches, and not a whole lot of difference.
Torque doesn't drop off the table and rpm doesn't go through the roof.
RPM is an acronym for Ruins Peoples Motors. No need to run 8300 rpm.
You can easily get 400 hp from a well thought out 331. Paul Wright built us a 331" motor for our road racing Nova, and with an rpm limit of 6200 rpm it put 335 hp to the rear wheels, through the mufflers using a 2-bbl carb. 350 block, 307 crank, PM rods, flat top pistons, iron heads, VicJr manifold and a street roller cam with 225° duration. A lot of attention to the machining, ring sealing, valve job, etc. If you can find 5 places to pick up 5 hp, it all adds up. For example, the carb hat we installed over the 2-bbl was worth 8 rwhp. The exhaust system is also a good place to find hp.
 

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High RPM = High dollar

If you're serious about it I'd get in touch with a head company for their recommendation on a head that will flow enough to make the power you want. Then decide on an intake. Take those choices to a good cam designer and let them have at it. High rpm generally isn't going to be cheap though.
 

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“I'm considering building a high rpm race motor out of this nice old small journal 1967 327 “

I have never heard of building a race motor for torque. Now, the tow truck motor.....hahaha
 

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Seriously I find it interesting how simular the air cooled VW engine and the SBC is. Each is just like a box. You can put in small parts, medium parts or large parts and lo and behold the power goes up the larger the parts. Why folks choose small stuff is beyond me.
 

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No replacement for displacement...On a naturally aspirated build.
For dump trucks ?


L79, The Underdog
For other highly touted, super fast "muscle cars" and the like, those that could out-run an L79 generally didn't win by more than a few car lengths. We're here to tell you that most of them wondered what the heck was under the hood of that stock-looking Chevy.”

Again, from Super Chevy
 

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For dump trucks ?


L79, The Underdog
For other highly touted, super fast "muscle cars" and the like, those that could out-run an L79 generally didn't win by more than a few car lengths. We're here to tell you that most of them wondered what the heck was under the hood of that stock-looking Chevy.”

Again, from Super Chevy
Yep that L79 was a beast, back in the day. So if I was to put a well built 327 up against my well built 421, the 327 would out perform it?? I’m lost. I would build a small cubic inch deal if it was a rules deal. Otherwise why put almost the same money in say a 283, rather than something that you won’t have to work as hard to make the power? Like a 383, 406...etc.
 

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I like doing different things for a challenge. Anyone today can buy the best and biggest stuff and make hp. There are tons of 700 hp pump gas cars that can't get out of the 12's. So HP is a sales pitch and a number. I still enjoy the intricacies of building a good engine. If you are looking for high hp numbers of course build a giant engine. But for the fun of building an engine, do something different. It would take a TON of a lot more money to build a small block to make the power that my 565 did naturally aspirated. So small doesn't necessarily outrun big.
 

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Seems that in the age we are in, where a hot performance rebuild retains the stock block, sometimes the crank, and little else....nearly every thing else, except a few bolts and maybe some tins, will be aftermarket at this level of engine building.
So now you are staring at the fact that you can build 383+ and especially 400-412-415-421" engines to turn the same rpm for the same cost outlay.....and thus the 327 is stripped of it's only advantage from back in the day.
No longer, the "RPM King"....

But if you are determined to do it, ...really DO IT.

Agree with what G2072 said, forget about torque, it's gonna be what it'll be and that's it....we are after upper rpm horsepower and that means spin the damn air pump.

4..30+ gear, 4000+ rpm stall means you don't need torque below 3500 rpm.
Heads on the bigger side like 195cc on up to some 210-215 cc heads, solid roller cam, Single plane intake like a Strip Dominator or maybe the Weiand Team G with some rework.....carb you've already got lined out.
Go to a longer aftermarket rod like 6.25" in a sportsman level rod, light pistons, and about 13.5:1 comp on E85 or race gas.
Don't bore it any more than it takes to get it cleaned up, to keep as much cylinder wall thickness as possible...I'll gladly trade in 5-6 cubic inches for more bore wall thickness in a stock block.
Stud rockers and girdle with regular monitor checks on valvetrain health or step up to a shaft system.
Spin it to shift about 7600-7800 rpm, and out the back around 8000 rpm finish line.
Depending on the tire size might take a lot more gear than even 4.56 to do it.
Definately do not skimp on the torque converter, spend $600+ on the converter from a good builder.
 

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Discussion Starter #19
“I'm considering building a high rpm race motor out of this nice old small journal 1967 327 “

I have never heard of building a race motor for torque. Now, the tow truck motor.....hahaha
6500 rpm x 300 torque = 371 hp
6500 rpm x 400 torque = 495 hp
Next !
Please
 

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Discussion Starter #20
6500 rpm x 300 torque = 371 hp
6500 rpm x 400 torque = 495 hp
Next !
Please
And BTW the world class builders ALLWAYS build for torque.
Between about 1.35 and 1.47 to 1 torque to cubes.
So yeah I'll build for torque every time.
Go and get your black and decker circular saw and I'll chew it up and spit it out with a worm gear saw EVERY TIME
 
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