68 L71 Head/Cam upgrade suggestions
Thread Starter
Burning Brakes
Joined: Jul 2016
Posts: 767
Likes: 74
From: Blaine MN
68 L71 Head/Cam upgrade suggestions
I have a 68 Vert. with CE block L71 that I'm getting ready to buy AFR 305cc Heads for and would like to know if I'm making the right choice with these heads.
I have the original Heads/Cam now and just got Mustang Dyno #'s of 331TQ and 283 HP@53xx with 12.5afr at wot (cracks in Harmonic Bal. rubber so no higher rpm pulls).
I've calculated 10.5:1 for the new ratio with the AFR heads and want to run 91 Octane.
I'm planning on keeping the Tri-power (non negotiable), it's a 4spd, 4:11 axle car. If I upgrade to a new Cam/rockers etc. (still deciding on Hyd. or Solid roller) what kind of TQ/HP should I expect. 6500/7000 max RPM, 1 7/8" Headers.
I'd really like to hear from someone with a similar 427 setup that has dyno numbers. This will be mostly a street car with an occasional road course day.
I have the original Heads/Cam now and just got Mustang Dyno #'s of 331TQ and 283 HP@53xx with 12.5afr at wot (cracks in Harmonic Bal. rubber so no higher rpm pulls).
I've calculated 10.5:1 for the new ratio with the AFR heads and want to run 91 Octane.
I'm planning on keeping the Tri-power (non negotiable), it's a 4spd, 4:11 axle car. If I upgrade to a new Cam/rockers etc. (still deciding on Hyd. or Solid roller) what kind of TQ/HP should I expect. 6500/7000 max RPM, 1 7/8" Headers.
I'd really like to hear from someone with a similar 427 setup that has dyno numbers. This will be mostly a street car with an occasional road course day.
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If you never intend to stroke it to a 496 or larger, I'd get the 265s or 290s at the most.
Jim
Jim
Thread Starter
Burning Brakes
Joined: Jul 2016
Posts: 767
Likes: 74
From: Blaine MN
Thanks for posting dyno numbers guys, I had Chris at Straub quote me a package and he was est. 550hp and your posts support it. I think I'll do Compression and Cyl. Leakage tests next. With 50K on the engine, maybe it's tired. I'm heading towards pulling the Engine and going through the bottom end as well as 0.030 bore/hone and new pistons with 1/16" top rings.
