Hi guys, I'm in the process of rebuilding the 272 that was in my 56 f100, I don't think it was the original engine, seems to be a 57 (ECG) and the thermostat housing is angles to the side (could just be a replacement) but I'm guessing the 272 is out of a passenger car.

But anyway, I got the heads off and cleaned up and they seem to be two different heads. One is ECZ-G and the other is COAE.

I had a look at the identification chart and they have different compression and cc's. Will this be a problem? I'm rebuilding it because when I got it running it just didn't sound right, although there were a lot of other problems that contributed to that.








Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

The answer to your question is both yes and no.

The engine will run with mismatched heads.  The compression is lower and intake valves smaller on the C0AE heads, so not only will you have a difference in compression, you will have a difference in flow.  These differences can cause tuning challenges.  Each banks will have different fuel and timing demands, so you have to find a compromise that will work.
It will run much better with a matching set of heads, ideally another ECZ-G.



Lawrenceville, GA

Dennis.  Where are you located?


NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

Charliemccraney, thanks for the information, that might have been why, out of one exhaust manifold there was the slightest amount of blue smoke. I noticed this when I had the engine out, trying to get it running. Also with the timing, I just couldn't get it right, not sure it the miss matching heads were to blame there.

Noshortcuts, I'm in Sydney Australia. Which makes it hard to get my hands on a lot of the gear you guys have readily available.


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

The idle may be a bit rough with two different heads on the engine.  The ECZ-G head would be the better of the two heads on the 272.  Using the COAE head will have the compression ratio lower on the 272 versus what you would find on a 292 engine.  Another option is to find another COAE head and have them both milled so that they are both the same cc's and with smaller combustion chambers to bring the compression ratio back up some.  If it’s any consolation, the 1957 272’s (U.S.A.) did come with the ECZ-G heads.

Lorena, Texas (South of Waco)

Ok thanks Ted,

I think ill put it back together and get it running, meanwhile i'll look for another ECZ-G head to pair up with the existing. It should be ok for the time being, the truck won't be on the road for another few years.

Do you think there will be a detrimental effect on the engine in the long run with these different heads, or will it not know too much of a difference?


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

I get a number of core engines here where the heads are mismatched.  While the engine may not run smoothly, I don’t see it being something that will hurt the bottom end of the engine in the short haul.

Lorena, Texas (South of Waco)

Dennis.  I was hoping that it was practical to help you out with a cylinder head.  In working with a Forum acquaintance in Australia a couple of years ago on some y-block parts, it was astounding what the shipping customs' issues were.  I can't imagine what it would cost to ship a 60 pound cylinder head with hardware to you.  Correct me if I'm incorrect on my assumption...



NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

Ted, noshirtcuts,charliemccraney,

Thanks for taking the time out to sit down and answer these novice questions I have.

I have noticed the great support this forum has. I think it's unreal, there is know way I could learn what I have learnt in 6 months without this website and its generous members. I remember posting when I first got the engine six months ago, with photos pointing at bits and pieces on the engine asking what's this, what's that?! Unknown to me at the time Ted was one of the first to reply, later on I just happened to stumble upon an article wrillen by Ted and I thought... Hold on a second... This guy is building some of the fastest yblocks around and he just answered my post telling me I was pointing at a road draft tube!!!! Unbeleavable!.

So anyway thanks for the support.

I'll throw up a few pics if anyone wants a look at what I'm doing.


Engine when I got it
 


Coat of paint and some headers. (This is before I knew anything, just thought I couldn't hurt with a clean up and a coat) reverse rebuild!
 
 


Stepped the frame in to fit the Jag IFS nice and comfortablely.


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

Noshortcuts,

I'd be willing to have a head shipped over, I have already figured out that this engine is going to cost a lot of money to rebuild the right way and I have accepted that, the y block bug has got me and I now have a love for them! So I guess I'm on my way to being a true Y BLOCKER! Haha. So if you have one I'll be keen to see what you want for it!

Maybe send me a message.

Thanks Dan.


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.