Another 350
Thought I'd add my 350 to the thread. The engine is in a '68 firebird, m-21, 3.36 blown posi. I plan to go to long branch manifolds and 2.5" exhaust as this car will eventually go back to a 400. (I have not tuned either carb.)
Baseline:
Stock '73 350 (2v rated 150hp)
'73 #46 heads 96cc (after pulling these, I found 2 burned valves)
Stock 555 Cam
Performer intake and Edelbrock 850 cfm
2" dual exhaust through a set of glasspacks, stock log manifolds.
Swapped cam:
performer cam 204/214 .420/.440 110 LSA.
Timing @ 12* ini and 38* total
Swapped heads and carb:
'70 #16 small valve heads, shaved to 68cc.
SCR appx 9.9:1
Compression test appx 190 psi on all cylinders.
Timing @ 6* ini and 32*total to prevent detonation.
Change the carb to Edelbrock 650 cfm (appx 14.1:1 afr @ WOT)
Dyno results baseline, after cam, and after heads and carb swaps:
274 RWTQ @ 3100 rpm; 196 RWHP @ 4200 rpm -- baseline
274 RWTQ @ 3450 rpm; 205 RWHP @ 4600 rpm -- cam swap
293 RWTQ @ 3300 rpm; 228 RWHP @ 4750 rpm -- head/carb swap
Torque curve was nearly flat with 280+ from 2000 to 4200 rpm after the head/carb change.
Hope this information is useful to someone!
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