ZZ4 or Vortec heads
Heres what I am thinking, 350 4bolt bored .020 or .030 scat forged stroker, eagle H beam rods w/arp (600-625) grams, are these rods overkill? And the Vortec or zz4 head, performer intake. undecided about what pistions and cam and carb. now I have a carter 650 I am almost sure thats not enough. Could this get 400 hp/ 400tq at the flwheel at 4500 ft elevation
make sugg as needed, I can get the zz4 heads at about 650.00 and figure the vortces for about the some w/screw in studs and good for about 550 lift, but then have to buy the intake??
Thanks Tom
Last edited by SKYCOP1; Dec 15, 2004 at 12:57 PM.
Valve sizes: 1.94/1.50-inch intake/exhaust, 11/32-inch stem
Intake runner: 170 cc
Chamber: 64 cc
Valvesprings: Single wire w/damper 1.235-inch od, 0.875-inch id 75-pound seat pressure @ 1.700-inch installed height Coil-bind @ 1.150 inches
Valvespring seat: 1.300-inch od, 0.850-inch id
Valve-guide seals: Viton rubber positive seals Total 0.450-inch retainer-to-seal clearance
Max valve lift: 0.420-inch (allows 0.030-inch retainer-to-seal)
Rocker stud: Press-in, 3/8-inch diameter No guideplates
Intake bolt pattern: Four bolts per side
Spark-plug style: 14 mm, ¾-inch reach, tapered seat
Spark plug: AC R44TS, AC R44LTS, AC Rapid Fire #8 RS12YC Champion, Autolite 104 or 26, ACCEL 516, Bosch HR10B or HR10BX, HR9DC
Rocker arm: Guided style necessary
Valve cover: Center-bolt style
The Fast Burns are the ones that come on the ZZ4 are generally of the complete combustion concept similar to the Vortec but are aluminum have old style intake and all that. The ZZ4 has .509 lift so the springs and such aren't a problem. Also the ZZ4 engine has roller rockers so the fast burns may already have the proper screw in studs for the rockers too. As I recall the best flowing heads outside of GM ball park were the AFR series heads , The Trick Flows they had the best mid lift flow. This is according to in depth flow bench testing Chevy Hi Performance Magazine did on Dozens of heads ,,, check out their website its in there somewhere. Good Luck,, if you got the DOUGH you got the GO,,,, My vote is the Fast burns
Thanks for the Reply,
Tom
I haven't done much research on the AFR heads but you are the first person I have ever heard talk about problems with them. Anyway if your going with the 383 a carb, the performer manifold which is only designed for off Idle to 5500 max,, then I think the smaller heads would be o.k. pumping up your bottom end torque,, especially if your going with a lower compression ratio. However if not then its a new game in my opinion. Check that sight,, and some of their buildups and see what you think then.







