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Camshaftkid

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Question...will '73 "587" heads fit comfortably on a '69 273?

After reviewing some answers (thanks guys), looks like the "587" heads will not fit comfortably on a '69 273.

Obviously, I can't attempt to treat this '69 Dart with the original 273 / 904 with a noisy 7.25" like a '67 Nova. I have to make some real decisions here, with an attempt to wake up this 273. Engine is OK, however aged with it's 2V. I was hoping to pump the HP to somewhere near 300. May not happen with this small of engine. I can pull near 400 easy enough out of a 327, Mopar seems to have disposed of the 273 in place of the mighty 360. So, it looks like an engine swap is my only real alternative? Help!

Let me please ask one last question of you guys. I was at the Goodguys car show in Pleasanton, CA today and spoke with a guy there about his '69 Dart, and picked his brain about my dilemma. His car has a 340, and he (obviously) swears by that engine, which I can understand. He too was plugging the 340 and 360 as most guys who own Mopars do. He also poo poo'd both the 273 and the 904, and advised me to install either a 340 or 360 with a 727. At one point I asked him value wise, which would be the better resale value...the car with it's original 273 / 904 or an installed 360 with a 727? He jumped right away with the value being greater with a 360 and 727 transmission. I don't want to be too attached to the originals if with the same amount of work and cost I could generate a more valuable car. Those who gave me the best responses to my previous question, can you please tell me what you think about this. Glenn P.S. I found only 4 Mopars at this entire show. It was more of a Chevy fest than anything. But I was lucky to find this one guy with a car very similar to what I'm trying to achieve with mine...a good looking, head turner Mopar, that also has plenty of power.
 
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Yeah, but they'll drop compression down into the 7s. Welcome aboard. Go to the Welcome Wagon and introduce yourself and tell us about your Mopar(s).
 
Camshaftkid said:
Question...will '73 "587" heads fit comfortably on a '69 273?
Click to expand...

Those are 360 heads with 1.88" intake valves and 1.60" exhaust valves...

You may need to notch the bores for the larger valves to clear the smaller 273 bore...
 
Camshaftkid said:
Question...will '73 "587" heads fit comfortably on a '69 273?

After reviewing some answers (thanks guys), looks like the "587" heads will not fit comfortably on a '69 273.

Obviously, I can't attempt to treat this '69 Dart with the original 273 / 904 with a noisy 7.25" like a '67 Nova. I have to make some real decisions here, with an attempt to wake up this 273. Engine is OK, however aged with it's 2V. I was hoping to pump the HP to somewhere near 300. May not happen with this small of engine. I can pull near 400 easy enough out of a 327, Mopar seems to have disposed of the 273 in place of the mighty 360. So, it looks like an engine swap is my only real alternative? Help!
Click to expand...
Welcome to FABO! If it's a '69, it's unlikey to have a 273, 318 or 340 was it for smallblocks. If it's a 270 trim level model, probably had a 'teener for motivation stock. If so, the 1.88/1.60 valves will fit fine. To My knowledge, '67 was the last year for the 273, but You could have a transplant. Let Us know what You find.
 
69 could indeed be a 273, but check the casting numbers on your block. Pistons in those years are almost zero deck, so compression will be fine. 1.88 intake valves fit without notches, but check valve clearance to bores without the pistons. You can mill the 587's to get to 65 cc, then 300 hp is pretty easy. Plus you won't have to rebuild it as much as a 327.
 
Go pull a 5.9 Magnum from a pick and pull and swap it in. Use a carburetor and intake instead of EFI. You can use the serpentine belt setup or pull the front end off your LA engine and use the v-belt. Looks just like the LA. If you want to get crazy, swap heads and cam!! That will wake up your Dart!!

Here's a How-to article another member did Diy - Magnum Swap!!
 
Camshaftkid said:
Question...will '73 "587" heads fit comfortably on a '69 273?

After reviewing some answers (thanks guys), looks like the "587" heads will not fit comfortably on a '69 273.

Obviously, I can't attempt to treat this '69 Dart with the original 273 / 904 with a noisy 7.25" like a '67 Nova. I have to make some real decisions here, with an attempt to wake up this 273. Engine is OK, however aged with it's 2V. I was hoping to pump the HP to somewhere near 300. May not happen with this small of engine. I can pull near 400 easy enough out of a 327, Mopar seems to have disposed of the 273 in place of the mighty 360. So, it looks like an engine swap is my only real alternative? Help!
Click to expand...
Welcome to FABO You could build a 300 horse 273 but it's much easier to start out with a bigger engine. Magnum swaps are quite popular. Roller cam and better heads are a plus.
 
Killer6 said:
Welcome to FABO! If it's a '69, it's unlikey to have a 273, 318 or 340 was it for smallblocks. If it's a 270 trim level model, probably had a 'teener for motivation stock. If so, the 1.88/1.60 valves will fit fine. To My knowledge, '67 was the last year for the 273, but You could have a transplant. Let Us know what You find.
Click to expand...
Numbers indicate original 273 / 904
 
Killer6 said:
Welcome to FABO! If it's a '69, it's unlikey to have a 273, 318 or 340 was it for smallblocks. If it's a 270 trim level model, probably had a 'teener for motivation stock. If so, the 1.88/1.60 valves will fit fine. To My knowledge, '67 was the last year for the 273, but You could have a transplant. Let Us know what You find.
Click to expand...

Camshaftkid said:
Numbers indicate original 273 / 904
Click to expand...


The last year for the 273 was 69...

67 was the last year for the solid cam/adjustable rocker arm 273's...

68 & 69 273's had the same hydraulic camshaft and rocker arms as the 318 for those years...

Refer to the charts in this article:

Factory V-8 Engine and Cam Specs by Year 1965-1975


1967.JPG



1968.JPG



1969.JPG
 
krazykuda said:
Those are 360 heads with 1.88" intake valves and 1.60" exhaust valves...

You may need to notch the bores for the larger valves to clear the smaller 273 bore...
Click to expand...
Your response seems to be the most seemingly accommodating, again, I'm not skilled in modifying Mopar engines for higher HP (most of my experience is Chevy). This is why I'm asking. I chose the 587 heads because a pair were readily available to me, and it seemed to me that installing them would help the engine breathe better, along with a 268 cam, 4 barrel intake with 650 CFM carb, and headers, with a 2000 stall converter. Because I have to work on the rear end anyway, it was my plan to install an 8 3/4" Sure-Grip for better traction (should I require it). This was my plan. I want the car to be "streetable", not for racing. Thanks for your info.
 
Camshaftkid said:
Your response seems to be the most seemingly accommodating, again, I'm not skilled in modifying Mopar engines for higher HP (most of my experience is Chevy). This is why I'm asking. I chose the 587 heads because a pair were readily available to me, and it seemed to me that installing them would help the engine breathe better, along with a 268 cam, 4 barrel intake with 650 CFM carb, and headers, with a 2000 stall converter. Because I have to work on the rear end anyway, it was my plan to install an 8 3/4" Sure-Grip for better traction (should I require it). This was my plan. I want the car to be "streetable", not for racing. Thanks for your info.
Click to expand...


Those heads will bolt on a 273 and will have better flow, but the bores may need to be notched for the valves to clear and also a little extra so the flow doesn't get 'shrouded'...

They will improve performance, but you may need to notch the bores for clearance if you want to use them...

Even with the drop in compression from the larger combustion chambers, there will be an increase in performance... The higher flow will offset the compression drop...
 
Camshaftkid said:
Question...will '73 "587" heads fit comfortably on a '69 273?

After reviewing some answers (thanks guys), looks like the "587" heads will not fit comfortably on a '69 273.

Obviously, I can't attempt to treat this '69 Dart with the original 273 / 904 with a noisy 7.25" like a '67 Nova. I have to make some real decisions here, with an attempt to wake up this 273. Engine is OK, however aged with it's 2V. I was hoping to pump the HP to somewhere near 300. May not happen with this small of engine. I can pull near 400 easy enough out of a 327, Mopar seems to have disposed of the 273 in place of the mighty 360. So, it looks like an engine swap is my only real alternative? Help!
Click to expand...


You can get a 318 cheap and the 360 heads will bolt on and work without having to notch the bores... I've even run the larger 2.02" 340 valves on 318's without any problems or notching the bore...

You will still have a compression drop with the 360 heads on the 318, but as I stated before the increased flow will offset the compression drop....

The 318 will bolt in directly for the 273 and will even use the same engine mounts...

But if you upgrade to a 340 or 360, they take a different left side engine mount which are hard to find these days... Shumaker makes the mounts for them, but they were sold off to a different company and I'm not sure if they have started making the 340/360 mount that you need...

Here's a link for the mounts, make sure to change the engine size box for the 340/360 mount as the 273/318 mount is the default... I tried to change it for you in the link, but make sure it's set for the proper engine size... Maybe call first before ordering them to make sure that they are available...

[/URL]

Edit: I tested the link and it goes to the proper 340/360 mount size...
 
krazykuda said:
You can get a 318 cheap and the 360 heads will bolt on and work without having to notch the bores... I've even run the larger 2.02" 340 valves on 318's without any problems or notching the bore...

You will still have a compression drop with the 360 heads on the 318, but as I stated before the increased flow will offset the compression drop....

The 318 will bolt in directly for the 273 and will even use the same engine mounts...

But if you upgrade to a 340 or 360, they take a different left side engine mount which are hard to find these days... Shumaker makes the mounts for them, but they were sold off to a different company and I'm not sure if they have started making the 340/360 mount that you need...

Here's a link for the mounts, make sure to change the engine size box for the 340/360 mount as the 273/318 mount is the default... I tried to change it for you in the link, but make sure it's set for the proper engine size... Maybe call first before ordering them to make sure that they are available...

[/URL][/URL]

Edit: I tested the link and it goes to the proper 340/360 mount size...
Click to expand...
Hi, I'm trying to save the original engine and trans. I was told when I bought the car that it had a 318.
However after owning it, and doing some research, it turns out it has the original 273 engine in it. It just seems "Frankensteinish" to pull the original engine out and use something else...know what I mean?
 
Camshaftkid said:
I'm trying to save the original engine and trans.
Click to expand...

The 273 Commando (higher compression, slightly larger cam, and 4 bbl) is a very fun engine. It doesn't really come alive until it hits 4500 rpm, and then it pulls hard for only 273ci. I kinda miss it in my 66 Barracuda-- but the warmed up 5.9 is fun too!!
 
Your plan is sound, no need to trash everything. 273's are sweet street motors that love to rev, so think 340 when making mods. high pressure oil relief spring, windage tray, make sure you use large intake ports for a 340 or 360 with those heads. I assume .450 ish lift cam, you should be fine. Make sure you find true TDC when you swap heads and centerline the cam.
 
Camshaftkid said:
Hi, I'm trying to save the original engine and trans. I was told when I bought the car that it had a 318.
However after owning it, and doing some research, it turns out it has the original 273 engine in it. It just seems "Frankensteinish" to pull the original engine out and use something else...know what I mean?
Click to expand...
I stand corrected, just never came across a post '67 with one personally, glad You have the original mill. No matter Your post, somebody will tell You to not "waste Your time", & drop a stroker/ big block in it.
Do what YOU want, enjoy the project. Peace.
 
the 587 valves will fit without hitting, more cam will make more power vs comp ratio , cylinder fill creates higher cylinder pressure , which makes more torque and more horsepower. nothing wrong with a 273, very good motor, just do what you desire. i've raced and drove my 273 years ago, as a legal jr stocker, and drove it, ran 13.31. just food for thought.
 
Camshaftkid said:
Hi, I'm trying to save the original engine and trans. I was told when I bought the car that it had a 318.
However after owning it, and doing some research, it turns out it has the original 273 engine in it. It just seems "Frankensteinish" to pull the original engine out and use something else...know what I mean?
Click to expand...
Most on here are not pro 273/318 and push 360 endlessly, we all known the benefits of displacement but you want to do a 273 nothing wrong with that, 66fs knows the 273 I follow his advice if that's the route you want to go.

Plus your build plan sounded good to me.
 
273 is a great little motor, no reason not to run it. If it really is the original 50+ year old motor I wouldn’t change anything but intake and exhaust. A small 4 bbl and some long tube headers is all you need.

Once you start swapping heads, cam and raising compression, things can get loose on a stock bottom end.
 
66fs said:
Your plan is sound, no need to trash everything. 273's are sweet street motors that love to rev, so think 340 when making mods. high pressure oil relief spring, windage tray, make sure you use large intake ports for a 340 or 360 with those heads. I assume .450 ish lift cam, you should be fine. Make sure you find true TDC when you swap heads and centerline the cam.
Click to expand...
Thank you for your help.
 
MidnightSwinger said:
273 is a great little motor, no reason not to run it. If it really is the original 50+ year old motor I wouldn’t change anything but intake and exhaust. A small 4 bbl and some long tube headers is all you need.

Once you start swapping heads, cam and raising compression, things can get loose on a stock bottom end.
Click to expand...
Thanks for your help.
 
273 said:
Most on here are not pro 273/318 and push 360 endlessly, we all known the benefits of displacement but you want to do a 273 nothing wrong with that, 66fs knows the 273 I follow his advice if that's the route you want to go.

Plus your build plan sounded good to me.
Click to expand...
Thanks for the advice.
 
perfacar said:
the 587 valves will fit without hitting, more cam will make more power vs comp ratio , cylinder fill creates higher cylinder pressure , which makes more torque and more horsepower. nothing wrong with a 273, very good motor, just do what you desire. i've raced and drove my 273 years ago, as a legal jr stocker, and drove it, ran 13.31. just food for thought.
Click to expand...
Thanks for your help.
 
66fs said:
Your plan is sound, no need to trash everything. 273's are sweet street motors that love to rev, so think 340 when making mods. high pressure oil relief spring, windage tray, make sure you use large intake ports for a 340 or 360 with those heads. I assume .450 ish lift cam, you should be fine. Make sure you find true TDC when you swap heads and centerline the cam.
Click to expand...
.477 / .480
 
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