Are 68' C80E Heads Any Good?

Mustang78

New Member
Feb 8, 2006
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Aberdeen, WA
So i got this 68' 302 longblock, already bored to a 306 and in good shape for 100 bucks, i know a guy that does good port work, would it be worth it to run em as-is(with a rebuild of coarse) or have them ported also for a few extra HP? are these as good(or bad) as an E7?? i am currently running a stock 82' H.O. motor that's getting worn, with i think D9 something heads, i could also purchase a set of 70's(71 i think) 351W heads if they're any better, with the bushings for the head bolts of coarse, and do i need new head bolts for this? thanks!:SNSign:
EDIT: is the 68' block the one with the higher nickel content? i know the 69' is but im unsure on the 68'.

~Mark~
 
well if the heads are big plug then more than likely they are closed chamber sorta like the 289 heads like i got. they do need ported but over e7's you have the compression that they give you which takes a 9:1.0 motor to around 10:5.1 ! so yeah there better......
 
well if the heads are big plug then more than likely they are closed chamber sorta like the 289 heads like i got. they do need ported but over e7's you have the compression that they give you which takes a 9:1.0 motor to around 10:5.1 ! so yeah there better......
 
i did notice the spark plugs are bigger, and the chamber looked small, but then again i've never had my stock heads off my car so i wouldent know what to compare them to, with this higher compression do i need to run 92 octane? and what do you mean by closed chamber?
EDIT: using a tape measure the intake valve measured out at about 1.50" and the exhaust at 1.75"..that good? i read that one guy was running 351W valves in the same heads, so they must be the same size or very close, right?

~Mark~
 
your factory heads are open chamber meaning big 60-62cc and those heads are closed chamber meaning smaller around 54-56,yeah if the valves are original you might want to change those stock H.O. e7 valves will fit, i have to run 92-93 octane in mine !
 
If you've got the 4V head (C8OE-F) with markings like the first pic, the chamber will be shaped like in the 2nd pic and be approx 54cc.

Otherwise you've got the 63cc chambered C8OE head.

It's likely you have a 1.78/1.45 valve setup which was factory.

I had a set of the 4V heads on a 306. I put in the bigger 1.84/1.54 valves and did some intake/exhaust gasket matching. For a factory iron head, not bad. :nice:
 

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Interesting thread here. I got a 68 302 4v motor because it was laying around, and the blocks are supposed to be good ones. All the numbers matched the 4v codes.

I really did not think the heads were worth using, especially over E7's. My guess is that by the time you get the rebuild done, install new, larger, valves, new guides, adjustable rocker studs, springs. and add porting costs, a set of iron Gt40's is the same price. I looked this cost comparison over hard a few years back, and went with the GT40's. I had them on the car for $700.
For a bit more you can have Edelbrocks or AFR's.
 
rd:

I totally agree with you on the $$$ issue.

About the only advantage these and the other early heads have, is a bump in the c/r over most late heads. That is if you get the smaller chamber ones.

By the time I was done freshening up my 4V heads (screw in studs, bigger valves, hard seats, etc.) I had way too much in them. But they got the job done for me at the time.

Anymore, a set of GT40 (or P) or used aluminum is a better choice.

Best of course is new aluminum. ;)
 
the 68 4V heads were the first year of the 302 ( 1968) and it was ONLY a 4 barrel engine, the only 2 barrel was the being phased out 289!! The valves are the stock small block 1.74/ 1.46 !! the heads will work well.. however the newer intaker runners and exhaust runners WILL pull more power Stock for stock!! BUT, the newer heads will drop the compression a lot and the increase in flow will be LOST in that compression drop!! Aslo if not done already.. they will need hard exhaust seats do to the unleaded gas of today!!

Options: GT40's / GT40P's / E7s are all better than the C8's !! cool??

Now the compression loss... mill the heads a max of .040 and the compression will be back to the C8 CC's. At .040 there will still be NO intake interface issues!!

Adjustable rocker.. Instead of paying the machine shop to machine for the screw in studs.. there are kits that will screw into the pedistals and carry all the hyd roller spring pressures ( 140lbs installed 320 lbs on the nose) and the kit is almost half the cost of the machine work!!

Choice of the better heads.. STOCK? GT40s!!
2nd) Ported E7s !
3rd) Ported GT40s!

Hope this helps....

Just me...................................

Thumper

PS.. the newer heads will ahve to be drilled for the steam holes in the early blocks!! Tpr
 
thumper460 said:
the 68 4V heads were the first year of the 302 ( 1968) and it was ONLY a 4 barrel engine, the only 2 barrel was the being phased out 289!! The valves are the stock small block 1.74/ 1.46 !! the heads will work well.. however the newer intaker runners and exhaust runners WILL pull more power Stock for stock!! BUT, the newer heads will drop the compression a lot and the increase in flow will be LOST in that compression drop!! Aslo if not done already.. they will need hard exhaust seats do to the unleaded gas of today!!

Options: GT40's / GT40P's / E7s are all better than the C8's !! cool??

Now the compression loss... mill the heads a max of .040 and the compression will be back to the C8 CC's. At .040 there will still be NO intake interface issues!!

Adjustable rocker.. Instead of paying the machine shop to machine for the screw in studs.. there are kits that will screw into the pedistals and carry all the hyd roller spring pressures ( 140lbs installed 320 lbs on the nose) and the kit is almost half the cost of the machine work!!

Choice of the better heads.. STOCK? GT40s!!
2nd) Ported E7s !
3rd) Ported GT40s!

Hope this helps....

Just me...................................

Thumper

PS.. the newer heads will ahve to be drilled for the steam holes in the early blocks!! Tpr
i have to disagree with you in this line up! My ported e7s were dogs compared to my ported c9s.
 
It is good to disagree !! However the cost to "(with a rebuild of coarse) or have them ported also for a few extra HP? are these as good(or bad) as an E7??"

Clean and Mag heads ( 35-50.00 ?) install hard seats ( 110- 145.00 ?) Valve job after seats ( 125- 225.00 depending on type of VJ) Surface flat ( 60.00 ?) Ported ( 350-500.00 ported local shop/ 110.00- 150.00 Gasket match ?) Machine the steam holes (25.00?) Parts - seals-springs-possible valves.(?) Vs the cost of a set of Ported E7s with everything done / new springs .. seals..and bolt on ready ( 695.00) Or a set of GT40s off the net (250-400.00?)with a clean up/seals/valve job and surface (350.00?) and then there is the performance level of the port work...ect!!
 
thumper460 said:
It is good to disagree !! However the cost to "(with a rebuild of coarse) or have them ported also for a few extra HP? are these as good(or bad) as an E7??"

Clean and Mag heads ( 35-50.00 ?) install hard seats ( 110- 145.00 ?) Valve job after seats ( 125- 225.00 depending on type of VJ) Surface flat ( 60.00 ?) Ported ( 350-500.00 ported local shop/ 110.00- 150.00 Gasket match ?) Machine the steam holes (25.00?) Parts - seals-springs-possible valves.(?) Vs the cost of a set of Ported E7s with everything done / new springs .. seals..and bolt on ready ( 695.00) Or a set of GT40s off the net (250-400.00?)with a clean up/seals/valve job and surface (350.00?) and then there is the performance level of the port work...ect!!
i bought my c9s with all the work done already so i didnt have to pay the machining costs.