Quote:
Originally Posted by 67_C-30
Not true. The is a release from Sallee Chevrolet.
I built 2 limited late model dirt track engines with 906's last year, and one them powered the car to 7 feature wins. Some of the 906's that came on 2500's and 3500 HD's had a hardened exhaust seats installed instead of being flame hardened like the other 906's and 062's, and it is a little smaller than on the 060's and 062's, but on a flowbench the numbers are so minimal that you'd never know it in power production. If someone is still worried about it, a simple bowl blend makes them flow the same. The hardened seat 906 is actually a better head than any of them for racing because the hardened seat was installed because some of the Vortecs were cracking around the valve in extreme use in heavy duty trucks. A Jan '03 article by Chevy Hi-Performance started the "avoid the 906" craze, but it circulated as fact.
BTW, If anyone has any those useless, wretched 906's that they won't use, let me know and I'll PM you my address and shipping money!  |
The diference is the hardened exaust seats, not the appearance, while I have not ran Vortecs and have not had experience with the two castings, I am sure the difference in performance would be minimal if even noticable...but there is a difference.