I'm doing a budget build on a 350 I got on trade, partially just for the heck of it. By the time I sell the parts that came with it I'll have gotten my money out of it, but the bottom ends looks to be in good shape. (Top end was a 10.5:1 drag setup with a 3,000-7,000 cam and mid/high rise single plane intake.) This is the first engine I've ever seriously contemplated doing something substantially different than stock with, and am curious to plug the specs into a dyno program and see what it spits out.
And if anyone wants to comment from experience on what I can expect out of what I'm looking to assemble, feel free.
Chevy 350, standard bore, 4-bolt main, cast crank
Flat-top, double eyebrow TRW pistons
Factory "480" heads: 70CC chambers, 1.72/1.50 valves
Erson TQ20H square-pattern cam: 292 adv./214 @ .050" duration, .449 lift, 111 LSA, 4* advance
Edelbrock Performer dual-plane intake
The specs on the pistons say they net 8.5:1 w/76CC chambers and 10.5:1 w/64's, so the 70CC chamber should put the compression at 9.3-9.5:1. I run 89 octane in all my stuff to begin with so that should allow me to keep that policy. This is going in my old Suburban temporarily (figure the engine in it now that runs perfect and can be demo'd will sell for more) which only needs power up to about 3,500 RPM but will do well with a lot of torque. The heads are off the original-type 327 that is my end-game engine when resto time comes along, so if I do the heads now I can just swap them over when the rest of the 327 gets rebuilt. According to spec sheets the late 60's 4 bbl. 350's (255HP) had 1.72 intake valves so I'm optimistic it will be at least decent.
Also, the timing set on the engine in question is adjustable to -4, 0, or +4. With the advance already built into the cam, should I leave the crank sprocket at 0 or advance it to bring the power down more?
Like I said, this experiment is mostly for the heck of it - can't spend a lot of money, just looking to trade some parts and play around with some spare stuff I have to see what I can do.
And if anyone wants to comment from experience on what I can expect out of what I'm looking to assemble, feel free.
Chevy 350, standard bore, 4-bolt main, cast crank
Flat-top, double eyebrow TRW pistons
Factory "480" heads: 70CC chambers, 1.72/1.50 valves
Erson TQ20H square-pattern cam: 292 adv./214 @ .050" duration, .449 lift, 111 LSA, 4* advance
Edelbrock Performer dual-plane intake
The specs on the pistons say they net 8.5:1 w/76CC chambers and 10.5:1 w/64's, so the 70CC chamber should put the compression at 9.3-9.5:1. I run 89 octane in all my stuff to begin with so that should allow me to keep that policy. This is going in my old Suburban temporarily (figure the engine in it now that runs perfect and can be demo'd will sell for more) which only needs power up to about 3,500 RPM but will do well with a lot of torque. The heads are off the original-type 327 that is my end-game engine when resto time comes along, so if I do the heads now I can just swap them over when the rest of the 327 gets rebuilt. According to spec sheets the late 60's 4 bbl. 350's (255HP) had 1.72 intake valves so I'm optimistic it will be at least decent.
Also, the timing set on the engine in question is adjustable to -4, 0, or +4. With the advance already built into the cam, should I leave the crank sprocket at 0 or advance it to bring the power down more?
Like I said, this experiment is mostly for the heck of it - can't spend a lot of money, just looking to trade some parts and play around with some spare stuff I have to see what I can do.
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