Rebuild or replace?

[MOPAROFFICIAL]

Unfortunately, I think the 67 904 trans has a different input shaft and convertor hub. I'm not sure what convertor is available for a 67 down 904.

They just stick early guts into a later case.
Still old 19 spline , done it a few times.
Delenzi converters does it for me, about 180-200 bucks for one cut higher stall.
That way it works with the trans yet fits the larger register of the later crank.

My thought was he get a later yr 318 and build it. No sense building a 273 these days unless you have a real commando 4 brl car or something. No one will know cause it looks the same.

 

[66fs]

I was going by the fact that most don’t want to run gears stall etc..

Stock gears and stall or even mild step up will be closer to what a 360 needs than a 273.

The OP was talking about 275 hp 273 or 408 which either gonna need a complete drive train upgrade to match.

I was not looking at it that way. I was looking at it by the 275 horsepower. I know of a 273 (with .030 cast 2 barrel pistons, .030 Chrysler rings, 920 heads, Commando intake air cleaner and Prestolite distributor, Edelbrock 600, Isky E-4 solid cam, high pressure oil pump spring and a windage tray) that dyno'd at 265 horsepower. The Isky E-4 cam only has .425 lift and 260 duration. A custom solid cam should make a streetable 275 horsepower. That should work with his existing drivetrain. No mixing, no matching, no replacing, and able to last the next 50 years. This is similar to the 273 in my brothers 67 Barracuda, except he had an 8 3/4 rear with 3.23 gears and a sure grip. The engine has 300,000 miles on it, the original 904 has 400,000 miles on it, and the 8 3/4 has 350,000 miles on it. The D Dart 275 hp 273 was not street friendly, but was able to sing up to 7,000 rpm and available with 4 speed and 4.86 gears only.

 

[66fs]

About overheating, it sounds like leaking head gasket(s), poor fan, not enough radiator core, cracked heads, tune? Any or all.

 

[toolmanmike]

I was not looking at it that way. I was looking at it by the 275 horsepower. I know of a 273 (with .030 cast 2 barrel pistons, .030 Chrysler rings, 920 heads, Commando intake air cleaner and Prestolite distributor, Edelbrock 600, Isky E-4 solid cam, high pressure oil pump spring and a windage tray) that dyno'd at 265 horsepower. The Isky E-4 cam only has .425 lift and 260 duration. A custom solid cam should make a streetable 275 horsepower. That should work with his existing drivetrain. No mixing, no matching, no replacing, and able to last the next 50 years. This is similar to the 273 in my brothers 67 Barracuda, except he had an 8 3/4 rear with 3.23 gears and a sure grip. The engine has 300,000 miles on it, the original 904 has 400,000 miles on it, and the 8 3/4 has 350,000 miles on it. The D Dart 275 hp 273 was not street friendly, but was able to sing up to 7,000 rpm and available with 4 speed and 4.86 gears only.

I should have Dyno'd mine. Same combination only I have the Egge HP pistons. I was guessing 250 horse.

 

[66fs]

I should have Dyno'd mine. Same combination only I have the Egge HP pistons. I was guessing 250 horse.

You should have more than that. Unless you had to move your timing back for the high compression pistons.

 

[66fs]

My thought was he get a later yr 318 and build it. No sense building a 273 these days unless you have a real commando 4 brl car or something. No one will know cause it looks the same.

I guess, from my experience, new is worse. The 273 had all the good parts. Forged crank and rods, floating pistons, solid cam, better heads, we always built them, no special parts, just upgrade the cam add a windage tray and away you'd go. If you got hold of 68-69 pistons you had a zero deck short block. 340's were the same, only quicker. 318's needed special pistons, and only had low performance internals. 318 2 barrel engines did not make 230 horsepower, and were not worth racing. Like everything, if you throw enough money at them you can make anything run. I am not a drag racer like you, but all my friends raced or still race. A second or two in the quarter mile does not bother me. I want it all. Quickness, reliable to cruise all day at 100 mph, top end of at least 140 mph and get good gas mileage down around 70 mph. My brother and I put 500,000 miles on high performance 273 Barracudas from east to west and north to south. I love how a 273 zips up to 6,000 rpm effortlessly with a 4 speed and the sound of the old 2 1/2" straight through single exhaust running all out.

 

[ir3333]

wow, 273 or straight to 408? Both choices are costly but everything in between can make good power economically.
a warm 318 or 360 in a heartbeat or 340 if you stumble on a deal! JMO

 

[Exjouster]

What I would recommend is look for ant 318 car that runs good that has a shot body. That is what I do for guys that can't afford a motor. Complete Gasket kit paint and your good to go. There are some low mileage cars and trucks out there with good 318's and rusted beyond repair. I just did a 34k 318 runs like new. Total cost was around $500 with 4bbl intake ,carb , parts and paint . I also installed he trans. I put Valve seals in without removing the heads also. Should have taken the heads off but to late now. I pulled it from this 67 Barracuda. it was originally out of a 73 charger. Cost of the motor was free. it was left over from Todd's car we took the clip off of for his fast back. I alway see free motors on the web go get one. This is the same motor. The first thing I did was put it together and got it running good . Then removed it and painted everything.

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Awesome job!!

 

[ddartdude]

Still having issues with the cooling on my 67 Dart GT convertible, 273 4bbl, 904, 7.25 3:55. Still getting way too hot on 20+ mile runs, and burning oil. Pretty sure there is corrosion in the block that’s preventing flow, and likely a head gasket issue (some oil in the coolant).

Torn between seeing about having the 273 rebuilt (to the 273 Super Commando 275 hp specss) or getting a 408 stroker with about 400 hp.

I assume a pull, rebuild, and reinstall will run me around $3.5-4K ish, while prices on crate strokers seem to be right around 6k for just the engine, no labor.

Car is just a weekend cruiser, but is also dreadfully slow as is. My mechanic described the engine as “tired and worn”.

Guess the big question is whether the rest of the components will handle a stroker, and if changing to the bigger engine would increase or decrease the value of the car?

I have a 275+ hp 273 in one D/Dart with 5.30 gears in it. Totally not streetable. In my other one is a 360 - 380 hp Mopar crate engine from 1999. Those actually put out closer to 400 hp. I'd go this route. It has a slightly higher lift roller cam in it and it runs and idles smoother.

 

[Oldmanmopar]

A motor with bad compression rings will run hot. I would say that 273 is destined for the metal pile unless your looking to keep a numbers matching motor. They are not worth the effort. Just getting a good torque converter for that crank with the smaller snout will be costly. Look for a 71-74 318 with the trans attached. They usually have a decent converter from the factory. Your early timing cover with balancer will work for the correct water pump for the car. The only thing you will have to change is add the back-up light wires to the trans switch due to the later valve body. You will be way ahead of the game with a 318. 360 you will be hunting install parts that are not cheap. There will be a list of things just to install it.