I'm at that point (Head job vs New Motor)

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seabee

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Hi all, My latest project has been replacing my head gaskets, since I have had some outer-coolant leakage and random overheating troubling me for some time now, I decided to just tear the top of the motor off and go from there. To my Un-surprise the coolant channels were almost completely clogged, the valves look like ****, and it appears that this motor hasn't been touched in decades.
(Jerk that sold it to my wife said 5k on a rebuild)

My 273 has the odd-angle heads (1964-1965-2465315 casting #) but I do have the Eddy performer intake and carb already on it. I'm at that point where I'm deciding on either just getting a head job (No, not the kind you get in Thailand), and reassemble or getting a new motor. Luckily, All the other cars I have had came with strong motors so I have never priced a head job. My big question is whether it is worth it to get the heads done and reassemble this motor or just get a crate? I use this car as a daily driver, cruiser, random car show attendee and would like an economy small block that runs well.

After reading what I just wrote I realize that I really just want someone to hold me and tell me it will all be ok. Head Job optional. :cheers:

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If the bores aren't worn out 'i have a bore gauge to check them' i say scrape the piston off, do the heads... and run it till it smokes, then rebuild it later.


Bring me the heads, I can have them done for $350=cleaned, new guides, hardened seats, milled, valve job, new seals and assembled.
If theu need valves, its extra, same with the springs.
340 springs are like 45 bucks, valves are around 100 bucks.
Mesa machine in escondido is where id take them.

A short block for a 273 will cost around 1000-1300, pistons arent cheap.
Also If you want a lil port work, thats easy and id hook you up with a very good price as well.

almost nobody can beat that price and they do good work, have been around since the late 40's if im not mistaken and half of them are mopar guys that work there.
 
There's a perfect reason for the blocked coolant passages. The headgasket is in the way!
Maybe nothing is harmed, but with 1000's of miles... I'd be saying check deck flatness, and if that's okay try a new set of gaskets that don't block any coolant passages.
That gasket isn't blocked, it's corroded from the coolant trying to get to where it's supposed to be.

And everything is going to be fine! PM me for moral support and free parts
 
Thanks Justin,

I'll take you up on that offer. So far, this engine has not smoked or burnt oil. About 700 miles back we did a home-compression test and it looked good. Can you PM me a good time for you? My schedule is wide open and I'm in no hurry so whatever is convenient for you.

-Bill

If the bores aren't worn out 'i have a bore gauge to check them' i say scrape the piston off, do the heads... and run it till it smokes, then rebuild it later.


Bring me the heads, I can have them done for $350=cleaned, new guides, hardened seats, milled, valve job, new seals and assembled.
If theu need valves, its extra, same with the springs.
340 springs are like 45 bucks, valves are around 100 bucks.
Mesa machine in escondido is where id take them.

A short block for a 273 will cost around 1000-1300, pistons arent cheap.
Also If you want a lil port work, thats easy and id hook you up with a very good price as well.

almost nobody can beat that price and they do good work, have been around since the late 40's if im not mistaken and half of them are mopar guys that work there.
 
If the bores aren't worn out 'i have a bore gauge to check them' i say scrape the piston off, do the heads... and run it till it smokes, then rebuild it later.


Bring me the heads, I can have them done for $350=cleaned, new guides, hardened seats, milled, valve job, new seals and assembled.
If theu need valves, its extra, same with the springs.
340 springs are like 45 bucks, valves are around 100 bucks.
Mesa machine in escondido is where id take them.

A short block for a 273 will cost around 1000-1300, pistons arent cheap.
Also If you want a lil port work, thats easy and id hook you up with a very good price as well.

almost nobody can beat that price and they do good work, have been around since the late 40's if im not mistaken and half of them are mopar guys that work there.
I agree, if it doesn't burn oil, no ridge in the cylinders, and the oil pressure is good, just freshen up the heads and clean out the cooling system. Ream out the cooling passeges and flush out the block. Pop out a freeze plug on both sides and flush out all the crud that has settled in the bottom of the block. If you use distilled and antifreeze, you won't have future problems. Our San Diego tap water is murder on cooling systems! A couple of other good shops here in town is Speed Speciaties and Broadway Machine. I've had work done at both places and have no complaints. Definately have those 315 castings checked for cracks as they're common to have them.
 
I think I might have found another culprit in the random overheating, hard to start after running, -issue. The Heat-Riser Valve has been stuck at almost 90% closed for who knows how long. It won't budge at all.
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"PM me for moral support and free parts".... I LOVE this place.
 
Heck I'm in cold Michigan and don't have one. I do have the exhaust intake heat ports open--a 1/4 hole in each shim covering the port. Manifold warms up after 5 mins and engine is up to temp with in 10 mins
 
I have bills 273 #315 heads at 196.8 cfm int by .450 lift, perfect for his stock cam...
One head is done, the other i will finish tomorrow.
Will have exh flow numbers later today...
.100-54
.200-112
.300-168
.400-195
.450-196.8
.500-196

I did not do as much work to them as the '318 porting' thread, no guide shortening, no guide profile, just some bowl/short turn/straight wall above short turn work. If i do the guide profile and shortening...it will bring the numbers up at least 10 cfm and the low lift will increase at least 5-7cfm as well. these are a closed chamber head and shroud the valve a lil more...as well as the valve job difference, the angles are a lil wider....non the less these work really good and the power increase will be felt big time.
I will post pics before and after, as well as final port volume and chamber volume 'as is' then they will get a light mill before going back on.
ok didnt get to flow the exh yet, i did guide profiling 1st on int side ...and now these heads are flowing 203-204cfm int side by .450 :)
 
here are the latest numbers, all ports are within a few cfm through out the lift 'minus one port where the core shift was horrendous', yet it still flows close 'within 7 cfm'. The highest int flow of the bunch does 205cfm, the lowest of the bunch does 201cfm

INT/EXH PORT NO.6
----int--------exh
.100-61------na
.200-128-----94
.300-174-----114
.400-196-----133
.450-204-----148
.500-199-----153
.550-200
.600-204
fwiw comparison/how close the numbers r.
No.2 INT----No.4 INT
.100--59-------58
.200-122------125
.300-175------171
.400-199------198
.450-202------205
.500-199------200
.550-201------200
.600-203------205
I ported to get as high a low lift number as i could 'given stock valves and basic 3 angle' without bringing it to the point of no return. The cam is a .470 lift 262* solid now...so it along with these heads will work really well and make a drastic improvement in power for this lil 273.
My advice to u all is when working with the early heads '273' look the them over really good for core shift, it was so bad in one port that the guide had about .050 on one side and 3/8 on the other along with the straight side bowl which is usually proud into the bowl..was actually inverted ...

If the bore would allow, we could further...and even find more flow with nothing but the same work done.

but all in all, not bad for a port that flowed 172 cfm peak to start..
 
Compare the "almost clogged" cooling passages against your head gasket. It could be that the clogged ones are not passages at all, but purposely blocked off by the head gasket. If so, the build-up is normal. Your other coolant passages look normal, so don't slam the "5K since rebuild" guy yet.

I made that mistake in my dumF kid days when re-assembling my slant six and I found two ports didn't have a matching hole in the head gasket. For some stupid reason I decided to drill a hole to match. Started up and it started over-heating. I decided those holes were supposed to be blocked and were only there as part of the sand-casting process. Since everything was new, I was able to lift the head with the manifolds on and slide a new head gasket in place and the car ran fine for years after.

Too bad you didn't do a compression test before removing the heads. That would have told you if you need a ring job too, which can be done with the block in the car on many cars.
 
Compare the "almost clogged" cooling passages against your head gasket. It could be that the clogged ones are not passages at all, but purposely blocked off by the head gasket. If so, the build-up is normal. Your other coolant passages look normal, so don't slam the "5K since rebuild" guy yet.

I made that mistake in my dumF kid days when re-assembling my slant six and I found two ports didn't have a matching hole in the head gasket. For some stupid reason I decided to drill a hole to match. Started up and it started over-heating. I decided those holes were supposed to be blocked and were only there as part of the sand-casting process. Since everything was new, I was able to lift the head with the manifolds on and slide a new head gasket in place and the car ran fine for years after.

Too bad you didn't do a compression test before removing the heads. That would have told you if you need a ring job too, which can be done with the block in the car on many cars.



I do open the head gasket at the coolant passage between 3 & 4 'slant 6' near the manifolds, it did help cool those 2 cylinders better, but otherwise...yes, u leave the others alone cause the idea is to push coolant to the rear of the block then up and back through the head.
 
I'm watching this thread with interest. I may be in the same boat as seebee and I'd like to see how he's progressing with this!! Thanks for sharing guys!! Geof
 
Oh and i measured an int port=135cc
the chambers measured 66.5-67 cc

this is the casting #315 'closed chamber head', typically advertised at 64cc...lol
 
Dropped em off 5 mins before closing at Mesa today. Bill was a good sport about it. I'll get the cam specs from Schneider for them and after that they'll be built and ready to go.
 
Looking forward to a ride once its running, let me know if you need help with the tune.

You got it. I'm sure somewhere along the reassembly I'll need your Jedi Master advice. The cool thing about this project is the learning curve though. I can read the books and search the web all day long, but tearing it apart (and usually breaking it along the way) seems to work best for me.
 
Got the Cam and lifters yesterday from Schneider Cams in San Diego. Adding photo to archive.
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