I've done a ton of research- so now I'm really confused....

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hudskit

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Good evening All,

I've just purchased a very clean 66 cuda that while being in pretty good shape also runs terribly. It's a 273 2 bbl car- automatic all original to the car but until I can pull this combination and replace with a mildly built 360 /380 that I already own I was wondering how to make this car a decent driver until I get around to doing the engine swap. My thoughts were as follows: electronic ignition to start- simple Mopar swap out unit - orange box. I've tested the compression - and it runs from 125 to 135 across the board but smokes some when it starts. I've read as much as i could about swapping over to a 4 bbl carb and simple intake to get a better running car - but the initial low compression of the 2 bbl motor makes me think that if i can find a set of "302" 360 heads I can up the compression, get a better fit to the 4 bbl manifold , change to an Isky e4 cam in there and top it off with a small 4 BBl - probably an AFB or similar and still not have to pull the engine itself and get a reasonably decent driver.

Thoughts, anyone?

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KISS...

keep it simple stupid!

Points will work just fine, have for 100 years. Do a tuneup, points condenser, rotor, cap, plug wires and spark plugs.


2bbl will work flawlessly, rebuild it.

The 273 heads are closed chamber, dont think you will increase compression with any other head.

Oil burn on startup, might be valve seals, my 67 273 is doing it as well (150,000 on last rebuild, 320,000 on car as a whole)

One of these days i will replace them and see.

As for performance, who could want more than 19.8 in the quarter @ ~70 mph.

Its a good looking car (as barracudas go!:rolleyes:)

So tune it up and enjoy it, then when you are ready, mess it all up with your 360.

273s ROCK!
 
hudskit said:
Good evening All,

I've just purchased a very clean 66 cuda that while being in pretty good shape also runs terribly. It's a 273 2 bbl car- automatic all original to the car but until I can pull this combination and replace with a mildly built 360 /380 that I already own I was wondering how to make this car a decent driver until I get around to doing the engine swap. My thoughts were as follows: electronic ignition to start- simple Mopar swap out unit - orange box. I've tested the compression - and it runs from 125 to 135 across the board but smokes some when it starts. I've read as much as i could about swapping over to a 4 bbl carb and simple intake to get a better running car - but the initial low compression of the 2 bbl motor makes me think that if i can find a set of "302" 360 heads I can up the compression, get a better fit to the 4 bbl manifold , change to an Isky e4 cam in there and top it off with a small 4 BBl - probably an AFB or similar and still not have to pull the engine itself and get a reasonably decent driver.

Thoughts, anyone?

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The "302" heads are a good choice for raising the compression. Do not put 360 heads on it as they have big chambers and they will lower the compression, also the bigger ports and valves will hurt your low to midrange torque and throttle response.
 
Dana67Dart said:
KISS...

keep it simple stupid!

Points will work just fine, have for 100 years. Do a tuneup, points condenser, rotor, cap, plug wires and spark plugs.


2bbl will work flawlessly, rebuild it.

The 273 heads are closed chamber, dont think you will increase compression with any other head.

Oil burn on startup, might be valve seals, my 67 273 is doing it as well (150,000 on last rebuild, 320,000 on car as a whole)

One of these days i will replace them and see.

As for performance, who could want more than 19.8 in the quarter @ ~70 mph.

Its a good looking car (as barracudas go!:rolleyes:)

So tune it up and enjoy it, then when you are ready, mess it all up with your 360.

273s ROCK!
Click to expand...
I passed on getting a clean 1967 barracuda simply because of the lack of replacement sheet metal, quarter panels, fenders and the grille for them is outta sight too
 
Pull the valve covers.

If it still has the adjustable rocker arms, they may not have been reset for who knows how long.......
 
Personally I love the Ice blue with dark Blue interior! :thumbsup:

This Color combo sucks them in!!!!!!! Even in Reverse!

Look at a Pertronix setup to keep it hidden and original looking as it is! I suggest the Pertronix III and the other parts as per the instructions!

Clean up the engine bay for starters and enjoy what looks like a solid car.

Further do your mods After enjoying that car for a bit! You may change your mind!
 
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As already the heads on your 273 are small closed chamber; there would be no real benefit compression wise, to go to 302's other than hardened exhaust valve seats. You would have to grind away a portion of the head; smog port bump; on the drivers side to make your exhaust manifold fit/lay flat on the head. Cam shaft change........try a stock 360 hydraulic, by the numbers it's slightly bigger; more duration, equal lift; than the 235 hp cam
 
Dana67dart and AlaskaT/A hit on the nose . That car is gorgeous ! I would just tune it up and replace the valve seals. Might want to pull the oil pan and knock all the old seals out of the pickup tube screen ...lol
 
The factory already figured out how to get more performance out of the 273 — domed pistons for higher compression, plus high lift cam and 4bbl intake. Big valves don't really help since you're limited by the small ports. Swapping heads hurts the compression, and what you want to do is raise it. There really is no substitute for the Commando-style pistons. So go for drivability as suggested, and save your money for an engine swap if that's your bag.
 
Dan the man said:
The "302" heads are a good choice for raising the compression. Do not put 360 heads on it as they have big chambers and they will lower the compression, also the bigger ports and valves will hurt your low to midrange torque and throttle response.
Click to expand...

Dan the Man- the heads I have found are the 4323302 - listed as 85-86 318 LA series heads - which I'm hoping will raise my compression ration a tad - is that correct?
 
JBurch said:
As already the heads on your 273 are small closed chamber; there would be no real benefit compression wise, to go to 302's other than hardened exhaust valve seats. You would have to grind away a portion of the head; smog port bump; on the drivers side to make your exhaust manifold fit/lay flat on the head. Cam shaft change........try a stock 360 hydraulic, by the numbers it's slightly bigger; more duration, equal lift; than the 235 hp cam
Click to expand...

I've read - as my post said waaaayyyyy too much research - that these heads have small valves - 1.78 /1.50 which is the same as the original heads valve sizes - but have an aggressively small "Fast Burn" chamber that runs around 10cc smaller than the original stock heads - which is my "cheat" to get a higher compression ration without pulling the motor itself with the bonus of hardened exhaust valve seats so no worries about gas....but I could be totally wrong which is my concern.
 
My thoughts are get what's THERE running well first, then worry about conversions and such.
 
Its soon to be winter. Dont throw a dime at it, just ready the new motor and get it put in.
Why put anything into a motor you are taking out.
 
Absolutely a great point - I have 4 more years of 60 hour work weeks until i retire - so while i could steal a weekend for playing with the rebuilt heads and other parts lined up the big motor change just has to wait until i can take my time and enjoy the work . I also have an overdrive trans , 73 disc brake front end and 8 3/4 rear with the large bolt pattern to swap out on the car . I guess I just want to play with it just a little bit until I play with it seriously. And it really runs badly....
 
hudskit said:
Absolutely a great point - I have 4 more years of 60 hour work weeks until i retire - so while i could steal a weekend for playing with the rebuilt heads and other parts lined up the big motor change just has to wait until i can take my time and enjoy the work . I also have an overdrive trans , 73 disc brake front end and 8 3/4 rear with the large bolt pattern to swap out on the car . I guess I just want to play with it just a little bit until I play with it seriously. And it really runs badly....
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Then the most cost, time and effort effective in the NOW it to make WHAT YOU HAVE work. That's what I would do.
 
Like said a tune up should fix the poor running issues. Dont throw anymore $$ than needed for that. Enjoy it and use the $$ for new motor. Black Friday coming up?
 
hudskit said:
Dan the Man- the heads I have found are the 4323302 - listed as 85-86 318 LA series heads - which I'm hoping will raise my compression ration a tad - is that correct?
Click to expand...
Yes, that's correct. I agree with doing a full tune up on it. If it's going to be a while before you get the 360 together another area to look into is the exhaust. 1 1/2" primary tube headers with a 2 1/2" collector's. Exhaust pipe size of 2 1/4" is good. You want the smaller tube headers because they will scavenge the exhaust faster and more complete from the chamber, by doing this you won't be getting burned gases being mixed in with the fresh air/fuel mixture that was just brought into the combustion chamber. A improper designed / installed exhaust system can cost you around 50 horsepower. For the 360, 1 5/8" primary tube headers is good and a 2 1/2" exhaust pipes. A friend of mine lost power by going to a 3" exhaust system. If you plan on keeping your car on the street then 3" exhaust is to big.
 
1969383S said:
Personally I love the Ice blue with dark Blue interior! :thumbsup:

This Color combo sucks them in!!!!!!! Even in Reverse!

Look at a Pertronix setup to keep it hidden and original looking as it is! I suggest the Pertronix III and the other parts as per the instructions!

Clean up the engine bay for starters and enjoy what looks like a solid car.

Further do your mods After enjoying that car for a bit! You may change your mind!
Click to expand...
A factory electronic ignition system is fine. Wire it up per the instructions and install a curve kit and your good to go
 
hudskit said:
Good evening All,

I've just purchased a very clean 66 cuda that while being in pretty good shape also runs terribly. It's a 273 2 bbl car- automatic all original to the car but until I can pull this combination and replace with a mildly built 360 /380 that I already own I was wondering how to make this car a decent driver until I get around to doing the engine swap. My thoughts were as follows: electronic ignition to start- simple Mopar swap out unit - orange box. I've tested the compression - and it runs from 125 to 135 across the board but smokes some when it starts. I've read as much as i could about swapping over to a 4 bbl carb and simple intake to get a better running car - but the initial low compression of the 2 bbl motor makes me think that if i can find a set of "302" 360 heads I can up the compression, get a better fit to the 4 bbl manifold , change to an Isky e4 cam in there and top it off with a small 4 BBl - probably an AFB or similar and still not have to pull the engine itself and get a reasonably decent driver.

Thoughts, anyone?
Click to expand...

Nice Barracuda. My 66 Formula S was that same paint and interior. 273 engines were never smog motors. The compression ratio is about 9:1 and the pistons are only about .020 in the hole. 302 heads are a power loss on a 273. Both are closed chamber and without porting 302 heads flow less air. Plus the drivers side exhaust manifold hits the head. You do not need headers. Look at the Commando single exhaust with 2 1/2 inch pipe, straight thru muffler, and a straight thru resonator. It will work with your early A Body exhaust manifolds. To the problem at hand, if you have compression it should run very well. It is either spark or fuel. Use Taylor Spiro Pro wires, new cap and rotor, platinum plugs, new points and set timing to 10* BTDC. Rebuild the carb and make sure the fuel pump is working well. Replace the fuel filter. 273's with 2 barrel pistons are capable of making 265 hp with a small Isky E-4 cam with stock Commando parts. No 360 needed.
 
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