mrzods13

I called a local shop and they have a set of 915 heads ready to bolt on, hardened seats, bronze guides, the single springs with damper, etc.. They are asking $750, being the 915 heads are closed chamber would it affect the motor, having a lot of trouble finding 906 heads, I found a set of 452's but the header bolt holes are stripped out. Any opinions on the 915 heads as far as price being around where it should be.

TVLynn

It depends on what your compression is ?? The 915 will raise the compression about 1 point

mrzods13

It was a 2barrel 383 1968 chrysler newport

demetri

I don't know in the 383, but the 440 changed to the 906 from the 915 between 67 and 68. The advertised compression ratio was identical at 10.1, but that does not mean that the real compression was also identical. I have heard that the real compression ratio of the 906 440 was 9.6. The 906 had larger exhaust valves, and the performance of the 440 definitely improved with the 906 heads, regardless of what the compression ratio was.


The 383 may follow the same pattern, but given the reduced displacement, it may be less sensitive to the head design, until you go to the much higher rpm range.

mrzods13

I still have to go there to see if he has anything else besides the 915's. Just want cast iron I am not getting aluminum heads even though with the cast iron redone I am not far away from the price, I was told you should still bring aluminum heads to a machine shop and have them checked before bolting on.

TVLynn

Header bolts are not that hard to fix !! Especially off the car !!!!! 452's I believe already have hardened seats

Zoomer59

well the 915s were only made 1 year,so that would make them sorta rare,basicly they are a closed chamber style 906.the 452 is a modern version 906 set up for unleaded fuel.go with the 452.for 915s may make a good investment purchase though.