GM 14096188 heads

[squirt]

Was in the process of finding a shop to do some porting on my 990's when I came across these 14096188 heads. They came off a big inch blown Teague motor and have been ported and larger intakes installed. Question is the chambers on them are 116cc and the 990's are 118cc. What will that do to the CR? I was able to take the heads so I can have them flowed and evaluated before I purchase them, if good they will be cheaper than having my 990's done.
Don

[MikeF]

It should raise compression but likely only a few 10th's (from say 9.0 to 9.3 cr) so you'd be fine. They probably measure out to that because the head was shaved a little on the sealing surface. You could check the manifold to head dimension to match it up as good as possible as far as the ports are concerned. If the heads are in good condition, you might go for it. If the intake ports are alot bigger than the ones on your 990's (which are already BIG) then you might be stepping back a bit if you have a 454 or slightly larger. :boxed: But they will work ok and are functional.
By what I've seen so far, I'm still torn between large ovals and square ports on making the most power out of a jetboat. I have the 990's cause that's what my boat came with. My aluminum head change did not go as planned, so now I'm back to my original heads w/a different cam. We'll see what happens next.

[squirt]

heads are in the shop now getting flowed, I should know more in a few days. The 116cc vs 118cc chambers came from Mortec. I looked up the casting # when I saw they weren't 990's. It's not really important cause when I picked up the heads I realized there has been work done in the chamber area. I'll have to cc them to know what they are at.

[squirt]

Picked up the heads today from the shop that flowed them
std 454 bore fixture no pipe on ex
int / ex
100 75.89 60.22
200 137.39 117.90
300 217.88 153.72
400 273.46 173.37
500 309.48 185.09
600 339.72 192.38
700 362.39 195.55
800 375.29 198.09
Since these came off a marine motor they were stored while ex ports still had moisture in them. Heads have a light rust in ex ports and ex seats have some light rust spots. I'm gonna take them apart and see if I can lap the the ex valves to remove the light rust. Other than that they really don't need a valve job if I can lap them successfully