ir3333
Well-Known Member
How many guys have cc'd or had your builder cc your sm blk heads?
i thought most were around 70 -72...what were yours?
i thought most were around 70 -72...what were yours?
sm blk X and J heads
- Thread starter ir3333
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3 "J" sets @ 72cc's.
yellow rose
Overnight Sensation
I have measured them anywhere from 76 to 70 and I think the 70 cc heads had been milled but the dude told me they were OE. I think he was F.O.S. but that was the only set of factory heads I have seen with identical chambers, let alone chambers that small from the factory.
ir3333
Well-Known Member
...a friend thinks that the earlier 1968 and 1969 x heads were as low as 68cc's.
yellow rose
Overnight Sensation
Sheeeeeeeeeiiiiiit.
The small numbers I gave you are for the earlier heads, with 2.02 valves. I have never seen a head under 71 except the above mentioned heads.
It's easy and fairly cheap to buy a burrette and measure the chambers of everything you have.
Honestly, most of the ultra trick CNC dong beater heads are bigger than called out on the hero sheets.
Treblig
Well-Known Member
My original '69 318 heads were 69CCs and the 302s that replaced them were also 69CCs. Checked them myself!!
Treblig
Treblig
ir3333
Well-Known Member
i have a burrette and have cc'd a pair of 915's with 2.02 intakes ...72cc
I've cc'd original untouched 1.88 340 J heads with the lightest valve job, just to seal the valves. The largest chamber measured 72.8 cc's, the other 7 chambers were within -1.2 cc's. I have X heads but they were not mine since day one and I have not needed to redo them yet.
K.O. SWINGER
Meeting in the alley since 1976
my 69 Xs came in at 72cc and my 70 Xs 74cc
moper
Well-Known Member
All have been 72+.
My x heads came in at 77 cc's
dibbons
Well-Known Member
My 951 J heads (1.88) are all 68+ cc's, meaning I know I poured in at least that much alcohol during my first ever cc check of the combustion chambers. After the valve job I will do a recheck. These are old heads, so no telling the history on 'em.
What do you want them to be? It's a simple process to make them as large or small as you want.
ir3333
Well-Known Member
my short block is nearly complete... head cc requirements will be decided soon.
MOPAROFFICIAL
Oogliboogli
About a 1 cc'ish diff between those and the 1.88 version. The factory 2.02 tulip valve gives up volume in the chamber, meanwhile takes up volume in the port, more than the chamber. The same casting 915 intake port volume -155 cc w/2.02 & 160 cc w/1.88 is what I have found. Good heads for factory stuff, my current set I modified and run flow 250cfm by .400 and go over 280cfm @.500
FWIW If you want actual chamber cc, just to know what it is without crevis volume of plug "which is different from running chamber cc aka w/plug crevis volume figured in" take a spark plug and remove the strap, insulator, and fill it flush with some wax. That's is not how you figure final compression ratio of course any idiot would know this...its just independent logging of all volumes/crevis volumes. As for as cast chamber size... 67 cc was the smallest j head chamber I've ever come across, one out of 4 that were 69cc..then I have a set of stock J 2.02 that are 72cc
The casting specs online are all over the place, 273& 318 heads vary quite a bit, stock 302's at 64.4 , 273 315 @66-67c , 675 @68cc
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yellow rose
Overnight Sensation
I don't know why you'd change the spark plug to CC a chamber. The chamber has the spark plug installed when it's running. Your way is wasting time. The total volume of the chamber includes the spark plug you run.
MOPAROFFICIAL
Oogliboogli
Your post was a waste of time. I pointed that out in my reply, the difference between actual cc of the head...and running cc aka with spark plug. I've seen oily plugs used and air pockets in the crevices. If one was to build and modify a set of heads for sale, he could correct the chambers to a specific cc either way he wanted, no matter what you say...I know, omg, what are you gonna do??
Nothing wrong with having chamber checking plug laying around, switch heat ranges and the plug gets smaller...omg what now??
Stop nit picking.
yellow rose
Overnight Sensation
Wasn't nit picking. Pointing out how senseless it is to do what you are saying.
Good god what a waste of time.
No matter if your right or wrong, the bottom line is;
"His car his way."
Trashing him won't help and is extremely rude. Your way is not the only way even though you consider it the right & only way.
Express your opinion on how to do it and leave it. Trashing him, exclaiming it is a waste of time and repeatedly telling him what you think is right doesn't help the issue and only serves to make you look like an ***.
The best you have is to tell him; "Intold you so." When he comes back with a complaint.
MOPAROFFICIAL
Oogliboogli
He will bring up crevis volume but down play at the plug.too funny...He thinks I'm also mentioning it as to tell people to figure the final compression that way. Eager to argue and always right. Some issues there.
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yellow rose
Overnight Sensation
Take your pop psychology somewhere else.
Most guys aren't even CCing their own heads. And you want them to do a head with a modified spark plug.
Unreal.
Again, colossal waste of time. Exactly what did you learn?
YR
Still down playing people?
Seriously?
Relax. Go drink beer.... a lot of it. Take a break. Get laid. Jerk off. Just do something to relax. Go dyno test something! Change springs out on a head just because. You need a break.
Still down playing people?
Seriously?
Relax. Go drink beer.... a lot of it. Take a break. Get laid. Jerk off. Just do something to relax. Go dyno test something! Change springs out on a head just because. You need a break.
yellow rose
Overnight Sensation
Really? So it's ok to tell people to do stupid ****?
Again, you can use a plug filled with wax. What did you learn. It's stupid. Might as well use any valve you have laying around right?
I'm not in the habit of letting stupid off the hook.
I don't drink. Maybe you should quit drinking before you post.
That's not what I'm saying and you know it. So before you start putting words into my mouth again..... go re read.
So, anybody that doesn't do it your way is "Stupid?" Just wondering.
Besides, is it really needed to call people stupid? Shoe on the other foot for a minute. Do you feel good when people call you stupid? And when someone calls you stupid for something you do not know about very well, does that automatically mean you will follow there instructions? And feel good about it?
Sorry, I thought we were here to help and teach and learn.
Perhaps you should walk on back to yellow bullet.
Sorry, that above, is my line.
No go getcha self a beer and relax!
Stop acting an ***.
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