Can I use 67 273 heads on my 69 318?

-
cudajim

cudajim

cudajim
Joined
Jan 17, 2006
Messages
1,486
Reaction score
102
Location
Grass Valley, Ca.
I have a 69 318 with no heads and also have a 67 273 engine. Can I use the 273 heads on the 318 along with the 318 hydraulic valve train? I'm trying to go cheap.
 
Yes and they will give you better comp with 57cc chambers or 60 I think on the 67 's as opposed to 62 or 63?
 
Yup as long as there 67 not 64-65. You could mill .45 off a stock head get some real good compression on the early 318s pistons are not the deep inside 9:1 even 9:5.
 
Last edited by a moderator:
Just remember driver side rocker arm bar notch points to the front, passenger side notch to the rear. This is for oiling purposes
 
We built a 318 using 65 273 57 cc heads .used the 65 4bbl stock commando intake and afb. It ran great and made plenty of power
 
Slantsix64 said:
Yup as long as there 67 not 64-66. You could mill .45 off a stock head get some real good compression on the early 318s pistons are not the deep inside 9:1 even 9:5.
Click to expand...
64 and 65 are the ones you don't want . 66 and newer are interchangeable.
 
Use a .039" or .05" head gasket... as said, the '69' 318 piston tops are close to the deck. I assume these 273 heads are closed chamber ones, OP?
 
Thanks for the replies. It should be easy, I'll just pop the heads off the ole 273 and put em on the 318 with the 318 valve train and juice lifters. I'll let you all know how it runs.
 
cudajim said:
Thanks for the replies. It should be easy, I'll just pop the heads off the ole 273 and put em on the 318 with the 318 valve train and juice lifters. I'll let you all know how it runs.
Click to expand...
Woah there big fella. The 67 should be solid lifter and the 318 will be hydraulic. The solid lifter and hydraulic lifter pushrods are different. With the hydraulic cam you will need the hydraulic pushrods and the rockers and shafts off the 318. Be careful what you are doing here.
 
FWIW
I am running the factory solids on my smogger-teen factory hydraulic cam, no problems. I put 5 or 6 winters on that set-up so probably 25000 miles at least. Then sold the engine to my son who drove it about another 6 years.
I too can be cheap,lol. I had the stuff so nothing to lose.
 
cudajim said:
I have a 69 318 with no heads and also have a 67 273 engine. Can I use the 273 heads on the 318 along with the 318 hydraulic valve train? I'm trying to go cheap.
Click to expand...



toolmanmike said:
Woah there big fella. The 67 should be solid lifter and the 318 will be hydraulic. The solid lifter and hydraulic lifter pushrods are different. With the hydraulic cam you will need the hydraulic pushrods and the rockers and shafts off the 318. Be careful what you are doing here.
Click to expand...


As long as he uses the 318 valve train (cam, rockers, lifters, and push rods), he will be ok...

Or, he can use the 273 cam, lifters, rocker arms, and push rods in the 318...

As long as he keeps the proper compatible cam and valve train together, it will work...
 
valiantwagonguy said:
Yes and they will give you better comp with 57cc chambers or 60 I think on the 67 's as opposed to 62 or 63?
Click to expand...

Those are book numbers...

The 67 heads will be about 63 cc and the 69 heads will be around 69 cc...


cudajim said:
I have a 69 318 with no heads and also have a 67 273 engine. Can I use the 273 heads on the 318 along with the 318 hydraulic valve train? I'm trying to go cheap.
Click to expand...


Slantsix64 said:
Yup as long as there 67 not 64-65. You could mill .45 off a stock head get some real good compression on the early 318s pistons are not the deep inside 9:1 even 9:5.
Click to expand...


I wouldn't recommend milling the 67 heads... I put a set of 67 heads on a 72 318 with a .040" permatorque head gasket and the intake bolt centerline is too high and galls the intake bolts when I tried to install the intake... I have my intake at my head guy right now waiting to get milled for that set-up.... Once together, those heads and intake must stay together and not interchanged singly....

I don't get my heads milled to increase compression, I only have my head guy mill them to clean up the head to block face and make it true and square if it's off.....

Just bolting on the 67 273/318 heads with a .040" head gasket will lower the compression about 1 point...
 
Last edited:
cudajim said:
I have a 69 318 with no heads and also have a 67 273 engine. Can I use the 273 heads on the 318 along with the 318 hydraulic valve train? I'm trying to go cheap.
Click to expand...

I would consider throwing in a nice mild cam while you are going this way, it will really improve performance.... A nice mild grind about .450" - .470" lift and run about 268° - 280° duration.... Basically upgrade to a stock 340 cam (268/276 with .429"/.444" lift) or just a little bigger, but not too much bigger...

I would also put a double roller timing chain on while you are in there, it's money well spent...

I have used this true roller double roller timing chain from Edelbrock for decades and on all my engines... It's one step over the stock 340 chain... I have run them over 100 k and they are still good with minimal stretch... The efficiency gain and long term durability of this chain will pay for itself over and over in the long run... Your timing will be more consistent...

Edelbrock
 
krazykuda said:
Just bolting on the 67 273/318 heads with a .040" head gasket will lower the compression about 1 point...
Click to expand...
Don't you mean 'raise' the compression, KK? The 273 chambers (assuming closed chambers) will be smaller. The head gasket will be thicker; the net ought to be a few tenths increase in compression ratio on the'69 318. But that is assuming closed chambers on the '67.

If the OP's 273 heads are open chambers like the later 273/318 heads, then the thicker head gasket will lower compression about 0.3 points; not a whole point. It is still going to be up at 9:1; better than the later 318's. The OP could go with the .028" thick head gaskets and get back up 9.2-9.3.

But who knows what condition the cylinder bores, pistons, rings, and valves/guides are in and if it will make compression in all cylinders anyway! So the heads and gaskets are kinda a moot point....
 
nm9stheham said:
Don't you mean 'raise' the compression, KK? The 273 chambers (assuming closed chambers) will be smaller. The head gasket will be thicker; the net ought to be a few tenths increase in compression ratio on the'69 318. But that is assuming closed chambers on the '67.

If the OP's 273 heads are open chambers like the later 273/318 heads, then the thicker head gasket will lower compression about 0.3 points; not a whole point. It is still going to be up at 9:1; better than the later 318's. The OP could go with the .028" thick head gaskets and get back up 9.2-9.3.

But who knows what condition the cylinder bores, pistons, rings, and valves/guides are in and if it will make compression in all cylinders anyway! So the heads and gaskets are kinda a moot point....
Click to expand...

You're right..

I was thinking of when we had 360 heads with .065" gaskets on the 318 and we put the 67 heads and .040" gaskets on...

But still with just the heads, the 67 heads will increase the compression...
 
toolmanmike said:
67 273 heads are closed chamber.
Click to expand...
Thanks TMM.. I was not clear on if the SBM's had the 675 open chamber heads by '67... sound like not.

Which means that for sure the OP needs to use a .039" or thicker head gasket... the .028" thick head gaskets would be getting too tight on piston clearance to the closed chamber heads. Stand Felpro kit head gaskets at .050" thick would work and be cheap.
 
nm9stheham said:
Thanks TMM.. I was not clear on if the SBM's had the 675 open chamber heads by '67... sound like not.

Which means that for sure the OP needs to use a .039" or thicker head gasket... the .028" thick head gaskets would be getting too tight on piston clearance to the closed chamber heads. Stand Felpro kit head gaskets at .050" thick would work and be cheap.
Click to expand...
As long as you measure the clearance the op should be ok. I used the Mopar Performance version of the Mr Gasket1121G gaskets with a .028 compressed thickness on my 273 with the Egge 10/.5 pistons. I had close to .100 clearance and the pistons are out of the hole. The 318 slugs in the op's 318 are close to zero deck but still below. Dang, I should have taken a photo of the exposed dome.

041900951350[01].jpg
 
But your dome sticks up in the chamber; that is not the issue. The question is how much below deck was the flat area of your pistons...??

I'd suspect that the OP's early 318 pistons are < .010" below deck and probably < .005". If so, the the .028" thick gasket would give a piston to head clearance under .035". Sorry... way too close for me for worn piston rocking in the bores + a bit of rod bearing wear.
 
nm9stheham said:
But your dome sticks up in the chamber; that is not the issue. The question is how much below deck was the flat area of your pistons...??

I'd suspect that the OP's early 318 pistons are < .010" below deck and probably < .005". If so, the the .028" thick gasket would give a piston to head clearance under .035". Sorry... way too close for me for worn piston rocking in the bores + a bit of rod bearing wear.
Click to expand...
I wish I could measure the shadows in my photo.
 
nm9stheham said:
But your dome sticks up in the chamber; that is not the issue. The question is how much below deck was the flat area of your pistons...??

I'd suspect that the OP's early 318 pistons are < .010" below deck and probably < .005". If so, the the .028" thick gasket would give a piston to head clearance under .035". Sorry... way too close for me for worn piston rocking in the bores + a bit of rod bearing wear.
Click to expand...
I didn't figure there would be much of an issue. Ma Mopar used steel shim head gaskets with the pistons and heads without an issue. I don't remember much of the piston being below deck.
 
I took .030 off the heads to bring the chambers down and using the .028 head gaskets I got 9.68/1. I really don't think the Egge's are 10.5/1's If they would make them every buyer would be screaming that they need racing gas to run them. LOL
 
You must log in or register to reply here.
-

Back
Top