690 or 583 heads??
- Thread starter 55GMC
- Start date
An exerpt from our FAQ page:
Q: What is the difference between the hi-po #690 and #583 head castings?
A: The 583 head is thicker under the spring pocket. It's setup for higher spring height and pressure. The Z-11 cam had more lift and stronger springs. According to the Service Bulletins, the 583 heads entered production on Nov 18th, 1963 (into '64 production). They have nothing to do with the Z-11, but were needed because of the new 7735 cam (also known as the Z-11 cam, but this cam was in all 400hp and 425hp engines after 11/18/63). The cam had higher lift, requiring a taller installed valve spring height to avoid coil bind. In order to do this, the spring seats in the heads had to be machined into the casting. The 583 heads were cast with more iron in that area to allow for the machining. The valve head shrouding and valve diameters are the same and the heads are interchangable on any hi-perf engine (except the Z-11) as long as the '63 cam is used.
Q: What is the difference between the hi-po #690 and #583 head castings?
A: The 583 head is thicker under the spring pocket. It's setup for higher spring height and pressure. The Z-11 cam had more lift and stronger springs. According to the Service Bulletins, the 583 heads entered production on Nov 18th, 1963 (into '64 production). They have nothing to do with the Z-11, but were needed because of the new 7735 cam (also known as the Z-11 cam, but this cam was in all 400hp and 425hp engines after 11/18/63). The cam had higher lift, requiring a taller installed valve spring height to avoid coil bind. In order to do this, the spring seats in the heads had to be machined into the casting. The 583 heads were cast with more iron in that area to allow for the machining. The valve head shrouding and valve diameters are the same and the heads are interchangable on any hi-perf engine (except the Z-11) as long as the '63 cam is used.
M
Mr.Jimmy
Guest
Wouldn't it be nice if they did flow the same numbers....Then I could get rid of mis matched set too.... 
Missmatch?
I need a pair of 409 heads! How much for the missmatched ones Mr.Jimmy ?? My 409 currently has 348 heads topping the block
I need a pair of 409 heads! How much for the missmatched ones Mr.Jimmy ?? My 409 currently has 348 heads topping the block
M
Mr.Jimmy
Guest
I was talking with Mr Curt Harvy about this about a year ago about a topic darn near exact as this. The heads DON"T flow the same numbers....Thats why he talked me into a set of 583's.....If your running low rpms..low horse power, low lift cams numbers...than who cares about mis-matched stuff....But if your planning to throw some decent money into this project...with other nice parts....DO IT RIGHT!! 
We're not playing with $99.00 set of small block pistons and the $69.00 cam kit with the $30 Felpro gasket set from PAW!!! Then why waste a good set of heads on this....DO something creative...find another another head... and make a more like matched set.
I have bought and ran a mis-matched motor for a while...I was never happy with it...and it was just a street cruiser with a 700r behind it..that we would cruise to car shows out of state with it...and the most abuse it got was chirping it into second....and shifting at 5 grand... You guys don't even want to know how many sets of gaskets I bought from Show Cars trying to get this problem to run smooth!!! I think I could of owned stock in FelPro...lol
We're not playing with $99.00 set of small block pistons and the $69.00 cam kit with the $30 Felpro gasket set from PAW!!! Then why waste a good set of heads on this....DO something creative...find another another head... and make a more like matched set. I have bought and ran a mis-matched motor for a while...I was never happy with it...and it was just a street cruiser with a 700r behind it..that we would cruise to car shows out of state with it...and the most abuse it got was chirping it into second....and shifting at 5 grand... You guys don't even want to know how many sets of gaskets I bought from Show Cars trying to get this problem to run smooth!!! I think I could of owned stock in FelPro...lol
Show Cars parts catalog shows both heads have a flow rate of 260 C.F.M. 
583 and 690 heads
i had the machinest make sure the springs on my heads were set up the same (seat pressure and hight)..had them both decked .010 .. i mesuredthe porst and they are the same .. as far as flow only the flow bench will tell the story..i will be getting my engine going by early next year so i will let you guys know if it runs right .... if i could find someone to switch one head with to make a set of 690's, or 583's complete..the heads i have were virgin when i got them..other than pinned studs nothing had been done .. they still have the original valves and springs (very low milage)..
i had the machinest make sure the springs on my heads were set up the same (seat pressure and hight)..had them both decked .010 .. i mesuredthe porst and they are the same .. as far as flow only the flow bench will tell the story..i will be getting my engine going by early next year so i will let you guys know if it runs right .... if i could find someone to switch one head with to make a set of 690's, or 583's complete..the heads i have were virgin when i got them..other than pinned studs nothing had been done .. they still have the original valves and springs (very low milage)..
Kirby, I think you and Mike93Z need to get together and make two matching sets of the two mismatched sets you each have.
I think you both could come out better in the long run.
,,,dq
Mikes post
.
I think you both could come out better in the long run.
,,,dqMikes post
.
Fran Preve
Banned
Pinned studs were stock, done at the factory, all 690's and 583's. 583's are the better head (stronger spring pockets) but 690's more common and useful to numbers matching guys.