LSA decision help.
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From: Twin Cities, MN
LSA decision help. Stock LS1 bottom end (2002). Patriot 59cc Stage II heads (with comp dual springs). MLS gasket. Looking at the 228R cam. We know the static CR will be high, but should run with 92 octane and a tune. We want the smoothest idle we can get, and are leaning towards a 114 LSA, but wonder if a 112 LSA would be better for DCR, which (I think) would help with the pump gas. Not my area of expertise, never played with this kind off compression before (first time modding a Gen III). The engine is in a 67 Camaro with a T56 and 3.73 rear with 26.5 tall tires. Not looking to drag race, just want to hit 400rwhp so my wife gets some braggin' rights. Honest advice?
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Some LSA info A higher LSA will ALWAYS give you a smoother idle. If you are worried about detonation with a high mechanical compression ratio, then go with a high LSA. The higher the LSA the lower the mechanical compression PSI. Hence lower KR\detonation. 116 Is actually a good place. It will move peak power up a hundred RPM or two over the 114. Here is an approximate number: cylinder Press decreases 0.625%, per cylinder, for every 1degree increase in LSA. Therefore Peak HP & TQ Will decrease accordingly. However Your engine will run much smother and not break apart(throw a rod, bust a piston, etc.,.). GM stock cams range from 115-117.5 LSA. Stock Porsche's, Lambo's and Ferrari's even hit 119LSA. This helps them run to a 7500RPM red-line. And of course they still kick lots of ***.
I wouldn't take into consideration LSA or DCR... use them as reference.
possibly consider our SI4 cam 228º/228º .588"/.588" 113º+2
Judging from stock MLS gaskets that would be 8.75:1 DCR using the 59cc heads
http://www.speedinc.com/cont.cfm?cid=C0000150
possibly consider our SI4 cam 228º/228º .588"/.588" 113º+2
Judging from stock MLS gaskets that would be 8.75:1 DCR using the 59cc heads
http://www.speedinc.com/cont.cfm?cid=C0000150
