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I recently acquired a 327 (.040). I want to put it in my 67 chevy truck. I want to create a kind of sleeper, I don't care about top end, just massive torque! What can I get out of this engine and what can I expect to pay. Are there any websites I can look at?

Nick

Unfortunately, the 3 1/4 inch stroke on the 327 doesn't make much torque- - - - -they're much better at running higher RPM than some of the longer stroke engines like the 350 or 400. You can install a "RV" camshaft from one of the aftermarket cam grinders, and raise the compression by milling the heads or going to a set of 58CC 305 cylinder heads with a lot of custom valve work done to them. That puts you into premium-fuel range on compression, though!There's a machine shop in Florida selling the tricked-out 305 heads, but I don't remember their website at the moment. You'll be a lot better off doing some high-torque tricks to a 350, though. There's nearly 1/4" more stroke with that engine, and long strokes make torque!
Jerry

what is the application for the torque
ron

To add to what HotRod Lincoln said, you can also stroke a 350 to 383 c.i. put fuel injection on it and get even more torque. And I agree, if you are looking for low end torque, forget the 327.

I built up my 350 as a torque monster with the RV cam and some other things, and it is a monster. It'll pull up a wall. Go with the 350. They are everywhere and can be made to suit whatever the heck you're wanting.

if it comes to that you can also stick in a 572,
the question was though about a 327. maybe he likes 327's and nobody has honestly answered his question except to put in a bigger eng
I had a 212 cu in eng in my truck that would pull the [censored] onff most 350 engs. they say that size is not what matters but how it is used
my brother put a 454 with 750 ft lbs in his 28' fish boat 20 years ago. the motor only cost him about $28,000.00 20 years ago. the boys at the DDA shop where they ran it up on the dyno had their eyes popping when they read the values. that torque never really did him much good but was just a by product of what happened in the build to get him to another opening 200 mi away for another opening the next morning. it didn't bring in fish any better but got him there to more openings so that he had the opportunity to catch more fish.it did cost him 125 litres of gas an hour at 3/4 throttle
ron

Want low end torque? Put in a Big Block! You'll get torque at an idle.

Or go with a 292!

right

It sounds like he already has the 327. If it's a large journal block, and since 327's and 350's share a 4" bore, buy a rebuild kit for a 350 with the crank and now you have a 350, or buy a kit for a 383 stroker and you now have one of those. The kicker is, it has to be a late model large journal 327 block. I believe the 68-69's were the only large journal blocks.

John

If you want low end torque, add a diesel. Or go with a 355 or 383 if you want to keep it SBC. The over-square 327 is a high-reving motor due to the short stroke.

actually the torque for a stk 66 327 truck eng was 320 @ 2800 which is not that bad
ron

my 3.3 liter diesel has 365lb-ft at 1500 RPM. (Thats 200 cubic inches for those not metrically inclined)

that is quite a bit more than my 3.4 honda gave at [email protected] seemed like more though
how much did your eng weight
ron

While there's no substitute for cubic inches, sometimes you have to work with what you got.
My old 275hp 327 has plenty of low end, stock, and the next rebuild will enhance it. All the regular stuff: intake, RV cam, headers, a little head work, etc. I'm after a driver getting near 20mpg, with that sbc surprise when you grab a gear and drop the hammer.
Big blocks have lots of torque but they're heavy and expensive. 350 is probably a better block, but the wife won't like it if I bring home ANOTHER engine! If I had an unlimited budget, I'd go for a 500hp 400.
cm

I've built 500+ HP 327's, but they sure didn't get 20 MPG! Our best effort on a 350 was 610 HP at 7,200 RPM with a round track engine for the Nashville, Tennessee track. It was still building torque at that speed, but the car owner didn't want to push it to 7,500 or above on the dyno.
Jerry

Its a diesel, twice the BTU's per # than gasoline. Plus the little HX25 is near full boost.

my honda is a 1150 lb hunk of cast iron and is 2 cycle, this what they called detroits in the late 60's and early 70's especially when you are buzzing them up to around 3,000 rpm. they start to sound like those little honda 2 cycle engs in their motorcycles in the 60's
ron

A Detroit at 3,000 RPM is as close to a hand grenade as an engine can get! I've set a few Detroit 8V-71's to a upper governed speed of 2,500 instead of the factory-specified 2100 maximum. I'd only let a select few drivers take those trucks on the road. They had to promise NOT to push the speed above 2,300 RPM, and shift to a higher gear at that speed. The extra 200 RPM at the governor was there to keep the fuel rack fully open all the way to the shift point, not for extra engine speed!
Jerry

another man of strong convictions.I don't have an 8v71 but tere is no problem at setting the gov at 2750 for them. I have had the gov set at 2950 on my 453n for the last 19 years in my 64 4 x 4 panel until earlier this year when I pulled it to put a 283 back in and the 453 is getting a new life in a f250. you can set the gov on a 6v53 at 3550.
ron
I also had a 67 HD hayes with a 292hp 8v71 on logs in the mid 70's that would get run up to 2750 on logs offrroad. with a tandem axle I was pulling loads in the neighbourhood net 104,000 lbs and that honda thrived on it

I have seen 8V71's with bad SC seals go until they blow.

but back to the 327. it would be worthwhile to knowwhat sort of torque this fellow is looking , to know the application that he wants to use it in before any one can really make a statement. everyone perhaps has different values for what torque means, but if someone asks about a 327 and the next reply is buy a 350, it doesn't really answer the question does it. the better answer would be if you were interested would be why do you want to use a 327 and then if they say that they don't know why, then explain that a 350 might produce a little more torque. on the other hand there were a lot of 350's built that didn't put out that 275@1500
ron

the longer the stroke, the more torque you can make with a given piston diameter. Since the 327, 350, and 383 all share the same piston diameter, the 383 will have the most torque, the 327 the least. (Granted you need cam profile, combustion chamber geometry, etc. as part of the mix).

Since the 327 is a good over-square motor, it makes a great 9000 RPM motor (the 302 is better). The 383 is a great torque monster maintaining the 4.0 bore.

its been a while since I have even looked up to see if a 327 would accept a longer stroke crank, however if it would, that is the direction I would go.

but maybe he doesn't need that much and until he defines, we are just hypothisizing
what his needs are
ron

I see what you're saying, but when someone says the want a "torque monster", that usually manes they want lots of torque right off the bottom. Unfortunatly, the 327 isn't the best choice for a torque engine, given its relatively short stroke. For a true torque monster engine, you have to look at one with a long stroke, which leads to the 350, 383, or the big block and Deisel engines. The inline 6 engines, like the 235, 261, and the 292 also fall into this catagory.

Ah, yes "you need a long stroke for torque", the myth that will not die.

Everything else being equal the motor with the longer stroke will make more torque at any given speed. It may not turn as fast though.

Its the basic concept of the lever and fulcrum and how placement of that fulcrum and length of the lever affects the work done.

A longer stroke equals a longer lever. You're ignoring some basic physics if you think the relationship between stroke and torque is a myth.

Can a short stroke motor make lots of torque? Sure but its going to do so at a higher speed and with more work and dollars expended than a motor of the same size with a longer stroke.

With a 4 inch bore and 3-1/4 inch stroke its hard to think of a 327 as a candidate for torque monster when there are so many better options for making torque. Lots of racers have proven the 327 can make power, but they've done it by turning the motor fast, something a big bore short stroke motor is good at.

One of the car magazines, I believe it was Hot Rod, did a long stroke short stroke engine comparison a couple three years ago. What they found was if the cubic inches are the same, the short and long stroke motors make the same torque. When you break it down to the math, a small bore long stroke motor has less force pushing on a bigger lever. A large bore short stroke motor has more force pushing on a smaller lever. The resulting torque is the same. (Physics) They equalized the motors as close as possible except for the different bore, stroke combinations and came up with about a 1% difference in torque. And if I remember correctly the short stroke motor had the higher torque numbers. A good source to back this up is the resource manual that came with the old Desktop Dyno software. They do a very convincing job of showing cubic inches make torque, not stroke, and back it up with empirical (real world) data. In an engine build there are more limitations in increasing cubes through a larger bore than a longer stroke. So the long stroke gets the credit for the increase in torque, not the increase in displacement.

John

Well put John, I think I understand some of it.

There it is, Mr. Phillips.
I say: try that .040-over 327 and see if YOU like it...I'll bet you do. 3.73 or higher rear gear and a 4-speed will make a nice "sleeper" package.
Best luck.

cm

I completely buy the first part of that conclusion. And it is another reason a 327 will never be a torque monster. It's not big enough.

I believe I said that if everything else stays the same, longer stroke means more torque, and in that statement I intended to include the bore.

If there is no change in bore size or combustion chamber the longer stroke is going to increase compression with good results in addition to providing that longer lever. The result is more torque.

The magazine study is interesting, but does not persuade me to change my belief regarding the relationship between stroke and torque because changing the bore too invalidates the comparison.

I'm working on a torque monster for my GMC 1-ton tow rig. I'm starting with a Cadillac 500 because of its size and torque output.

The original poster is working with a 327, so be it. I bought a 66 1/2 ton High Torque 327 out of a junk yard a few years ago. Worked pretty good. Not a big block. Take it for a small V8.

Assuming a fresh build--Flat top pistons, cast, ie cheap. 69cc heads should be about 9:1 compression for pump gas. Big ports and fancy heads will not gain you naything in a truck. Use a dual plane intake, Edelbrock performer, Holley 300-38, Weiand has one too, can't remember the name. Small cfm 4 barrel carb, 600 or less, 500 would be better. Cam, run no more than a 292, but make sure it is on a wide lobe center, 114* or so. Probably a 280 or 272 would be better. Generic Summit or PAW brands are fine.
The other main thing that will assist you is gearing. There was a reason all these old trucks had some seroiusly deep rearend gears. To get heavy loads moving. Assuming a truck size tire, 30+ inches, expect to need at least 4.56 gears in the rear diff. Don't plan on cruising real fast down the highway however.

Devin

You're ignoring some basic physics if you think the relationship between stroke and torque is a myth

The "lever" concept was effectively put to sleep by SAE papers about 50 years ago. The extra leverage is almost exactly a cross-over against increased displacement in any engine you would use. In any case 4" stroke vs. 3" stroke isn't 33% more leverage except during part of the cycle (they nearly match during the remainder).

So, what does influence torque other than engine size?
1. static compression ratio (yes, not dynamic ratio, because after the "green line" is reached static = effective), and cylinder pressure varies with ratio (but only by E=(1-1÷R^K-1), where K is usually 1.4.
More compression will also give a different improvement based on what the original ratio was.
However, the frequent comment that "1 point of compression = X%" is simply not true, the change in efficiency doesn't vary with the actual change in ratio increments, or even in percentage change.
Going from 6:1 to 6.6:1 is more effective (+3.6%) than raising 9:1 to 9.9:1 (2.7%) even though the increase is 10% for both, and of course the larger actual change is greater for the higher ratio (.9 vs. .6).
2. volumetric efficiency; at low speeds pretty much anything has its maximum VE (85-95%) unless the cam is either very small (cylinder doesn't fill) or too large (late IVC, low expansion cycle, too much OL)
3. resonant (wave) tuning or inertia fill - both very unlikely in the RPM range you would use

We're left with displacement × CR, and displacement is far more effective (although not as efficient).

i know, im a little late on this, but maybe it will help him, or somebody. my opinion, is gearing. make sure its geared to do whatever you want to do...people are still supprised about the (old)medium dutys with "just a 6 cylinder! but its a BIG truck!" if you're mainly looking for torque, gear it for what you're doing.

Several variables can get into the math mix, including rod length/stroke ratio, compression, piston dwell time at the optimum cylinder position to absorb the maximum amount ot thrust, camshaft profile, intake/exhaust port velocity, BMEP, and a few other theoretical design exercises, but 50 years of dirt track racing have taught me one inescapable fact- - - - -While the calculator (and now computer) jockeys are doing their thing, stroker engines are out there on the track winning races!
Jerry

So, how about it N.Phillips from Minnesota? Have we talked you into it, or out of it? The 327, I mean.

cm

It's easy to build a world-beater engine on Desktop Dyno. Doing it on the track is a little different matter, and the math wizards with their theoretical knowledge and all the facts and figures don't always end up taking the victory lap.
Jerry

Just a thought, what do you think will make more power? A 302 Chevy with a 3" stroke and a 4" bore, or a 302 with a 3" bore and a 4" stroke? This example is a little extreme, but my moneys on the big bore short stroke combo. I could be wrong on this, but if I remember correctly, Nascar placed a limit on bore diameter several years ago as a way to limit horsepower. Bores were getting larger and strokes were getting shorter. Big bores, more room for bigger valves, and less shrouding equals more power.

John

A 3" bore and 4" stroke would only be 226 cid, not 302.