Which LSA for a....
#3
Mines on a 113.5lsa, but its more for nitrous then gearing. W/ your converter I dont think the lsa is gonna be a big worry, more of a question on is it strictly n/a and what kind of idle do you want.
Im no expert but thats pretty much how i understand it so far.
Im no expert but thats pretty much how i understand it so far.
#9
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Well I'll say this much, I decently sized cam like the V3 and a high LSA will make a poor DD cam. It will be sluggish down low and won't be spinnning high enough to take full advantage of its higher duration. Going with a cam like that makes better sense to have a tighter LSA so it moves the power band down lower and will probably see more up top to. I am not a guru by no means and could be out to lunch here but I know it kinda defeats the purpose of doing this. Something smaller on a tighter LSA will make awesome power across the entire power band while idiling great and making a great DD. If you are concerned, spend the extra few dollars and have a custom one ground out. I hear that Predator has made some very happy LS1'ers
#10
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Well I originally was going to go with a head cam package, but after talking to a few people they recommended just going with the V3...from who I have talked to this cam can be easily tuned and can be a great DD cam...coming from a guy who has it in a DD. I was just wondering which LSA to go with because he's got a m6 and mine is an auto. I thought I remember reading a while back, which i searched and couldn't find it, that it's better to go with a 114 LSA over a 112 LSA in an auto car. I guess I need to do more research...I thought I had most of it figured out. Thanks for all the help too!
#11
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Well I originally was going to go with a head cam package, but after talking to a few people they recommended just going with the V3...from who I have talked to this cam can be easily tuned and can be a great DD cam...coming from a guy who has it in a DD. I was just wondering which LSA to go with because he's got a m6 and mine is an auto. I thought I remember reading a while back, which i searched and couldn't find it, that it's better to go with a 114 LSA over a 112 LSA in an auto car. I guess I need to do more research...I thought I had most of it figured out. Thanks for all the help too!
You do not want a 114 lsa TV3 in a stock cube unless you are ready to rev to the moon. 111 will benefit the Auto powerband better but it will take some good tuning.
#12
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theres more than one person on this forum that knows cams buddy. been doing this for awhile, and with the stall and gear he is using, that pretty much told me on what profile range he was going to be in, that's if he knows what was good for his combo.
#14
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#16
a lot of cams have negative overlap.. every car out of the factory has negative overlap. Lots of turbo and FI cars have negative overlap.
#18
#20
If you are running a Forced Induction car, you want to keep overlap in the very low positive, zero, or even negative range.
Overlap is the amount of time in crankshaft degrees that both the exhaust and intake valves are open for a given cylinder. Overlap allows a cylinder to draw air from not just the intake manifold, but also the one in overlap. At low speeds, the cylinder drawing the air "chokes" on the exhaust drawn from the overlapped cylinder, hence why you hear a choppy idle. The car WANTS to die. At higher speed, the exhaust system has created enough air velocity to "suck" the exhaust air out of the cylinder in overlap, and the cylinder drawing from it will draw clean air from another intake runner. This is great in an NA situation. It's not so great for Forced Induction. The pressure inside the intake manifold, under boost, will blow it's pressure through the intake valve, and right out of the exhaust valve that is open during overlap. A little bit of overlap here CAN be good, as it blows some of the "dirty" air from the exhaust into the headers. This is also where backpressure comes in, but that's another story. Negative overlap here "seals" the intake stroke so that all of the boost pressure is going right into cylinder and nowhere else. Less overlap also provides more vacuum and a better idle.