What would you do?

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Rustyfish

Rustyfish

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I have a perfectly good 318 in my '66 Barracuda. It starts and runs consistently, gets decent mileage, but is stock 2 bbl setup. I may have access to an unrestored 273 Commando in unknown condition at a relatively cheap price, I think.

For my purposes I only really want my car to sound decent and have good torque/speed up to about 35-40 mph. It's just going to be a street driver that I can take to club events etc.

Given these conditions what direction would you go?

A) Mild build on the 318 with cam, intake, and carb?

B) Take a chance on the 273 Commando knowing that it might need rebuilding and new pistions etc.

Thanks
 
Easy answer. A 273, nowadays, is an expensive engine to build because of piston prices. A 318 is basically a 273 with a larger bore, there is NO performance advantage to a 273

The 318 already likely has better heads than the 273. Put a low rpm torque manifold (NOT an Edelbrock "Torker" which is NOT a low RPM manifold) use rather something like a Performer, a mild cam, not any larger than the old 340 factory class cams, and a good dual exhaust.

Put a decent carb on it, don't go too big there, and recurve the distributor or replace it. The change will be "more than" dramatic.
 
318 you already know it is a good motor.Just a intake,carb and dual exhaust will help it out alot.Then you add cam and springs and it will run better yet
 
That's what I figured really but wanted to reaffirm. It already has high flow dual exhaust with low restriction resonators, so just need the cam, intake, and carb.

Thanks!
 
What is the low price of the 273? The 273 has solid lifters, adjustable valve gear, an excellent small port intake manifold, good looking black valve covers, and a cool looking vintage chrome unsilenced air cleaner. It would be the correct original motor for your Cuda also. Personally I like the 273. For a cost vs performance stand point the advantage swings to the 318 due to the price and selection of pistons. Just about everything else is interchangeable between the 2 motors.

I would be assuming the 273 or any used motor you buy will need a rebuild regardless of what the seller says. A gasket set is cheep cost of disassembly to check it before you install it.
 
the 318 and 73 heads are same size valves and port sizes. the 318 head is open chamber, the 273 head is a swirl port and close chamber head. on the flow bench the 273 out flows the 318 head, imagine that!!!!
 
3.73 SureGrip and A999 with a 2.74 low gear; zero to 37mph in Shazzam time! Even with the 2bbl!!

This is about 50% more torque multiplication, than a 904 with 2.76s, so your teener will feel like 318 x 1.5 = 480cid in first gear only. Your Rs will be around 5000 at 37mph . Valve springs from a 360 or a 340 will prevent lifter pump-up.
3.55s will work too and calculate out to about 44% more.If you already have 3.55s and a 904, then the 3.73/999 is still plus 17.5%.

For first gear performance, just the 17.5% alone, is hard to duplicate with engine work, especially dollar for dollar.But the plus 50% throughout the entire gear? Fugetabowdit!

But If you already have the 3.55/3.73 & A999, then I would bolt on stuff like the guys mentioned. But I can't imagine that you do,cuz ,if you did you wouldn't be looking for more. heehee....You'd be looking for traction aids!
 
Depends on what you want from the car also! Do you want the bragging rights of having a commando motor where there could've been one, or just a 318 motor! Pound for pound for your intended purpose, either motor will give comparable performance with the exact same upgrades, and you are not asking for much by your description! With a gear and a little well spent money, you'll be doing burnouts in no time!! I personally like the bragging rights of the commando motor and would buy it to have around! If you take it apart and it is standard bore and it's not all worn out, you might be able to hone it and re-ring the original pistons, use as much as you can of the rest and make a decent "freshened up" motor, and have commando badges on with pride!!!!
 

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@Cosgig, that's about the only real reason I can see going with the Commando motor. I figure I could pick it up for about $600 plus another automatic thrown in that is still attached. Lots of great ideas to put it together for what I want without spending a great deal. I ask you guys because I'm more the body and paint type.

The rest of the drive train is stock, so looks like to get where i want will take some scrounging time but this, like everyone elses is a work in progress. Looking to have a fun journey with it.
 
A commando, besides the piston which don't get anywhere near it's advertised 10.5:1 CR is just a mild cam and not so good 4bbl intake. In starting in 1967 there was no more commandos and 318 was introduced
And from 67 - 69 the 273 and 318 are identical except the pistons of course.

Duals, mild cam and decent 4bbl setup will be all you need some 3.55 or so out back would be nice to and a 273 would need like 4.10-4.30 to match that.

A 318 with 4bbl and headers with a Comp XE262-H10 is said to dyno 282 hp above that compression becomes a problem squeezing hp out of a 318 cause you wouldn't want to put much more cam with a low CR engine after that heads start choking out around 325hp since they where designed for the 45 cubic inch smaller 273.

So no to the 273 and yes to some gears 4bbl and cam and maybe headers at least duals.
 
AJ/FormS said:
3.73 SureGrip and A999 with a 2.74 low gear; zero to 37mph in Shazzam time! Even with the 2bbl!!

This is about 50% more torque multiplication, than a 904 with 2.76s, so your teener will feel like 318 x 1.5 = 480cid in first gear only. Your Rs will be around 5000 at 37mph . Valve springs from a 360 or a 340 will prevent lifter pump-up.
3.55s will work too and calculate out to about 44% more.If you already have 3.55s and a 904, then the 3.73/999 is still plus 17.5%.

For first gear performance, just the 17.5% alone, is hard to duplicate with engine work, especially dollar for dollar.But the plus 50% throughout the entire gear? Fugetabowdit!

But If you already have the 3.55/3.73 & A999, then I would bolt on stuff like the guys mentioned. But I can't imagine that you do,cuz ,if you did you wouldn't be looking for more. heehee....You'd be looking for traction aids!
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Good point with the first gearing especially for most of us it about off the stop light fun. Gearing is always over looked. Our relativity low powered heavy cars need deep gears or what one would call strip only gears to get most out of them. Since the trade offs are too much most of us
that why its best to start with the biggest engine since we got to run 3.??:1 gears. Too bad the OD Tran swap is too much for most of us cause it gives you best of all world thats why every newer car has one.
 
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rustyfish said:
@Cosgig, that's about the only real reason I can see going with the Commando motor. I figure I could pick it up for about $600 plus another automatic thrown in that is still attached. Lots of great ideas to put it together for what I want without spending a great deal. I ask you guys because I'm more the body and paint type.

The rest of the drive train is stock, so looks like to get where i want will take some scrounging time but this, like everyone elses is a work in progress. Looking to have a fun journey with it.
Click to expand...

$600 is too much $$$ for a commando motor of unknown pedigree, I would offer/be in at $300 and either throw in the trans, or let him keep it!! Unless it is a 66 trans with the slip tailshaft for a U-joint driveshaft, then it would be a $75 piece!

Incidentally, I did the very thing you are asking about, I am running a commando motor in the blue 66, with 3:55 SG and an auto!! I am building a 340 motor to go in its place, and I am going to dress and paint it like a 2 bbl motor, and install the commando in my Signet convertible commando car so it has the correct motor! Yea, wow factor again!!!
 
cosgig said:
$600 is too much $$$ for a commando motor of unknown pedigree, I would offer/be in at $300 and either throw in the trans, or let him keep it!! Unless it is a 66 trans with the slip tailshaft for a U-joint driveshaft, then it would be a $75 piece!

Incidentally, I did the very thing you are asking about, I am running a commando motor in the blue 66, with 3:55 SG and an auto!! I am building a 340 motor to go in its place, and I am going to dress and paint it like a 2 bbl motor, and install the commando in my Signet convertible commando car so it has the correct motor! Yea, wow factor again!!!
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Sweet Cos. That'll be a nice deal. There is a 340 available to me here as well, but also not sure of the pedigree or condition but it is complete. If I bought everything I thought I might use around here, I'll have to buy a warehouse!
 
rustyfish said:
Would a package like this work well?

http://www.jegs.com/i/Edelbrock/350...LdXnGysA0DaEGXgc-zYBeSIYBpnbQG2BDRBoCG87w_wcB
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It would work well enough but I would look for a deal on a used intake,a good used carb,and buy my own cam and lifter set.Don't forget a new timing chain.The money you will save will cover all the gaskets and fluids easily.

You may not even need a cam for what you are doing.An intake and carb will help and with some fine tuning on the distributor it would likely meet your goals.


For example http://www.forabodiesonly.com/mopar/showthread.php?t=332798
 
Spend the $600 on your 318, as others mentioned you already have a good running engine so you have a good base to start with.
 
True commando motors or charger motors for Dodge did come in close to 10 to 1. The commando and charger went away in the 1968 model year not 1967. In 1968 the solid lifters went away as well. I have ran and owned 273 4bbl in my 1967 Dart Gt. Does the 273 come complete with valve covers, intake, carb etc? If it is just a long block then I probably wouldn't bother. Also the 273 does have a steel crank and the transmission and torque converter have a small input shaft, converter centering hub and small opening in the back of the crank that makes it so you can not bolt a newer converter and Trans in its place. Something to think about.
 
I've got a line on a performer intake for maybe less than $50 used. Sounds like that, a decent carb and I'm getting close. 302 heads a good compliment?
 
340dartley said:
True commando motors or charger motors for Dodge did come in close to 10 to 1. The commando and charger went away in the 1968 model year not 1967. In 1968 the solid lifters went away as well. I have ran and owned 273 4bbl in my 1967 Dart Gt. Does the 273 come complete with valve covers, intake, carb etc? If it is just a long block then I probably wouldn't bother. Also the 273 does have a steel crank and the transmission and torque converter have a small input shaft, converter centering hub and small opening in the back of the crank that makes it so you can not bolt a newer converter and Trans in its place. Something to think about.
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The Commando is complete, top to bottom. Looks like someone just removed it after sitting for 10 years.
 
rustyfish said:
I've got a line on a performer intake for maybe less than $50 used. Sounds like that, a decent carb and I'm getting close. 302 heads a good compliment?
Click to expand...

Don't worry about your heads. They all flow in the same ball park area. The 302's simply port out better than the others, or so they say.
 
I would bolt on a dual plane intake and 4 bbl with electric choke on the 318. also go with dual exhaust.
 
So you have to buy the 273 for $600, and then possibly spend the more money to get it running, like the 318 already is? Putting $600 into the 318 is a better bang for the buck, unless your just trying to be period correct. A small cam (<220 @ .050), aluminum intake, good carb, headers and that 318 will run circles around the 273. If you want period correct, dress the 318 to look like a 273, you'd probably fool the majority of lookers.
 
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