Grumpy I have access to get some 305 ho heads #14014416 that have about 30k miles on them. I want to put them on a hector mexico 2 piece rear seal bone stock 350 with bad valve guides. I bought this engine used and its a good running daily motor with bad heads. If the 305 heads will work my down will be minimal which is what I need. But I dont know if they will bump my compression to high. This is the casting off 350, heads 93417369. block 10066038. Thanks Dusty
305 heads
- Thread starter Dustytrix
- Start date
heres some links to casting number info
viewtopic.php?f=51&t=93&p=9023&hilit=mortec#p9023
http://www.summitracing.com/parts/tfs-3 ... /overview/
http://www.summitracing.com/parts/tfs-3 ... structions
you are aware theres reasonably priced aluminum heads designed for a small bore sbc that out flow standard vortec heads
14014416 305 HO, 80-85, 58cc, 1.84-1.5, 165/59cc ports, 7 bolt ex.
33417369 350, Gen.I, Crate motor, Hecho En Mexico, 7 bolt ex, 76cc, 1.94-1.5, flange VC holes, heavy castings
theres a difference of about 18cc, thats going to increase compression , and notice the valve size is smaller on the 305 heads
when we use this calculator
http://www.kb-silvolite.com/test/calc.php?action=comp
we find the compression jumps from about 8.6:1 to about 10.3:1
now that increased compression would normally result in about a 6% increase in torque but it will also get you into detonation levels with most pump fuel, and the valve size reduction will reduce the engines ability to reve up
you may want to read thru these threads
viewtopic.php?f=52&t=727
viewtopic.php?f=55&t=2718&p=7057&hilit=+octane+calculate#p7057
viewtopic.php?f=53&t=726&p=9291&hilit=quench+squish#p9291
viewtopic.php?f=51&t=93&p=9023&hilit=mortec#p9023
http://www.summitracing.com/parts/tfs-3 ... /overview/
http://www.summitracing.com/parts/tfs-3 ... structions
you are aware theres reasonably priced aluminum heads designed for a small bore sbc that out flow standard vortec heads
14014416 305 HO, 80-85, 58cc, 1.84-1.5, 165/59cc ports, 7 bolt ex.
33417369 350, Gen.I, Crate motor, Hecho En Mexico, 7 bolt ex, 76cc, 1.94-1.5, flange VC holes, heavy castings
theres a difference of about 18cc, thats going to increase compression , and notice the valve size is smaller on the 305 heads
when we use this calculator
http://www.kb-silvolite.com/test/calc.php?action=comp
we find the compression jumps from about 8.6:1 to about 10.3:1
now that increased compression would normally result in about a 6% increase in torque but it will also get you into detonation levels with most pump fuel, and the valve size reduction will reduce the engines ability to reve up
you may want to read thru these threads
viewtopic.php?f=52&t=727
viewtopic.php?f=55&t=2718&p=7057&hilit=+octane+calculate#p7057
viewtopic.php?f=53&t=726&p=9291&hilit=quench+squish#p9291
If I understand this right I will be needing prem gas but it would work. I only use this truck to go to work 9miles and around town. I will think about it some more but I know this is my fastest way out unless I find some more stock 350 heads. I am planning to build another 350 next year but this embarrassing blue smoke is getting to me. Thanks Dusty