Forced Ind. Cam
#22
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there are a few things you need to look into.
1. engine cubes
2. is it supercharged, or is it turbocharged.
Im going with a 408 stroker anda huge gt55 turbo. I think I will be going with a 232/232 cam design, however Im not 100% sure.
typically, supercharger cams will be split pattern designs, meaning 224/230, etc... and usually turbo cams will be reverse split, I.E. 230/224
Sometimes, depending on the buildup, you will keep single pattern cams, such as myself.
thats just the basics. It lift, duration, and lsa also are important depending on how extreme you are willing to go.
1. engine cubes
2. is it supercharged, or is it turbocharged.
Im going with a 408 stroker anda huge gt55 turbo. I think I will be going with a 232/232 cam design, however Im not 100% sure.
typically, supercharger cams will be split pattern designs, meaning 224/230, etc... and usually turbo cams will be reverse split, I.E. 230/224
Sometimes, depending on the buildup, you will keep single pattern cams, such as myself.
thats just the basics. It lift, duration, and lsa also are important depending on how extreme you are willing to go.
#23
Originally Posted by 94greencamaro
93Camaro and myself are running 14s because we are at 2700 ft in 90 degree weather . If we ran our cars in somewhere like California, i guarentee you we could get around a 13.3.
haha thats funny...my bolt on lt1 (similar mods as this guy) used to run 12's...then spun a rod bearing...lol
haha thats funny...my bolt on lt1 (similar mods as this guy) used to run 12's...then spun a rod bearing...lol
Are these guys for real? I've yet to see a modified (head/cam) LT1 go any better than 13.5 and that's at about 600ft above sea level and upper 70s.
Stock ones run 14s all day long.
#24
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Originally Posted by transam1998
Are these guys for real? I've yet to see a modified (head/cam) LT1 go any better than 13.5 and that's at about 600ft above sea level and upper 70s.
Stock ones run 14s all day long.
Stock ones run 14s all day long.
On topic: An fm-9 from futral, or something similar, will be a great forced induction cam.
#25
I would say if your going for a custom grind cam, go to comp cams, and go thru their whole cam questionairre, asks you a ton of questions I.E. Where do you want the power? what do you need it for? turbo or supercharger? how much horsepower? and such, that way, they are professionals, and you end up getting a good cam perfect just for you
#26
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ONealLaw
Ummm not exactly.. Your sort of on the right track but very far off base at the same time.
A forced induction cam has a wide lobe separation so you don't lose the boost that is being made.
You don’t NEED to have a wide LSA. It helps to prevent overlap but is not a requirement depending on the lobes you are using.
115 LSA is ideal.
Is that so.. Assuming the cam is not a split cam, would you still use a 115 LSA on the following lobes (All Are XER LS1 lobes):
3720 (269 @ .006 / 220 @ .050 / 143 @ .200)
3722 (273 @ .006 / 224 @ .050 / 146 @ .200)
3725 (279 @ .006 / 230 @ .050 / 151 @ .200)
3730 (289 @ .006 / 240 @ .050 / 161 @ .200)
I know I wouldn't.. Play with this link a little and tell me how you feel about that 115lsa.. http://users3.ev1.net/~black_ops/cam...Calculator.xls
Also the duration on the intake need to be larger than the exhaust so boost is not bled off.
This is not what causes boost to bleed off. In all reality it could cause more clean air to be lost do to overlap.
If you ever listen to the big pro stock blower race cars you will hear how smooth they sound but make gobs of power because they retain the boost in the engine.
Ummmm no.. They make gobs of power because they are:
Big cube, Alchy motors with big huge blowers that are purpose built to run on the raged edge and get rebuilt all the time. If you looked at their cam profiles, they would be nothing like what we see in our cars. They typically have an extream amount of duration which causes overlap which causes you “bleed off”.
I'm not trying to pick on you. I'm trying to clear up some misconceptions on cams. I want people to have good solid info.
Ummm not exactly.. Your sort of on the right track but very far off base at the same time.
A forced induction cam has a wide lobe separation so you don't lose the boost that is being made.
You don’t NEED to have a wide LSA. It helps to prevent overlap but is not a requirement depending on the lobes you are using.
115 LSA is ideal.
Is that so.. Assuming the cam is not a split cam, would you still use a 115 LSA on the following lobes (All Are XER LS1 lobes):
3720 (269 @ .006 / 220 @ .050 / 143 @ .200)
3722 (273 @ .006 / 224 @ .050 / 146 @ .200)
3725 (279 @ .006 / 230 @ .050 / 151 @ .200)
3730 (289 @ .006 / 240 @ .050 / 161 @ .200)
I know I wouldn't.. Play with this link a little and tell me how you feel about that 115lsa.. http://users3.ev1.net/~black_ops/cam...Calculator.xls
Also the duration on the intake need to be larger than the exhaust so boost is not bled off.
This is not what causes boost to bleed off. In all reality it could cause more clean air to be lost do to overlap.
If you ever listen to the big pro stock blower race cars you will hear how smooth they sound but make gobs of power because they retain the boost in the engine.
Ummmm no.. They make gobs of power because they are:
Big cube, Alchy motors with big huge blowers that are purpose built to run on the raged edge and get rebuilt all the time. If you looked at their cam profiles, they would be nothing like what we see in our cars. They typically have an extream amount of duration which causes overlap which causes you “bleed off”.
I'm not trying to pick on you. I'm trying to clear up some misconceptions on cams. I want people to have good solid info.
Last edited by LIL SS; 09-12-2005 at 04:05 PM.
#31
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Originally Posted by sycotic_reject
longrange4u, wha times are you running, you got a GT-2 or a GT-7?
#32
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sorryto keep sidetracking, but to be fair i never got my old setup to the track, but on the street it would outrun my freinds bolt on '00 ss that ran 12.9x's at the track...my old setup was jet hot LT's with dumped true duals, 4.10 gears, 315 nittos, spec stage 2 clutch and ram air with a k&n
Originally Posted by 777
There's something wrong if you can't find a head/cam lt1 do better than a 13.5, there's also something wrong if there is a bolt-on lt1 going 12.XX. Maybe the engine was in a miata
On topic: An fm-9 from futral, or something similar, will be a great forced induction cam.
On topic: An fm-9 from futral, or something similar, will be a great forced induction cam.
#35
I went with a Comp Cams Solid Roller, from their Extreme Street Roller lobe catalog:
Dur. at .015": I=268, E=274
Dur. at .050": I=230, E=236
Intake centerline is a standard 108.
Net Lift at valve: I=.575", E=.589" with 1.6 rocker ratio
LSA = 112
Overlap on this high-intensity cam is only 47 degrees.
This cam is working really well in my 383 and with the V-2 SQ S-trim Vortech, giving me a boost of about 8lbs. after the intercooler. It idles smoothly at 800rpm.
Redline on the motor is anywhere from 6000 - 6500. I am still testing to see where I should set it. I have not spun past 6200 yet. With a 7" crank pulley and a 3.12" blower pulley, Vortech's stated max blower redline of 50,000 will come at about 6200 engine speed. People here have said I can safely exceed that a bit - the consensus seems to be no faster than 10% above redline.
I am very happy with it so far.
Jim
Dur. at .015": I=268, E=274
Dur. at .050": I=230, E=236
Intake centerline is a standard 108.
Net Lift at valve: I=.575", E=.589" with 1.6 rocker ratio
LSA = 112
Overlap on this high-intensity cam is only 47 degrees.
This cam is working really well in my 383 and with the V-2 SQ S-trim Vortech, giving me a boost of about 8lbs. after the intercooler. It idles smoothly at 800rpm.
Redline on the motor is anywhere from 6000 - 6500. I am still testing to see where I should set it. I have not spun past 6200 yet. With a 7" crank pulley and a 3.12" blower pulley, Vortech's stated max blower redline of 50,000 will come at about 6200 engine speed. People here have said I can safely exceed that a bit - the consensus seems to be no faster than 10% above redline.
I am very happy with it so far.
Jim
#36
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Originally Posted by sycotic_reject
so how it go?? excited to see some numbers!
Specs on the Cam are: LPE GT2-3 207/220 .578/.581 118.5
Looks like this cam may produce some good Tq #'s... too soon to tell. Ask me on Friday :p
#39
Originally Posted by 1993CaMaRoZ28ofIdAhO
wow lets just talk a bunch of ****, bla bal 12s bla bal 13.5s i am not going to cam my car at 134k **** for brains. Come back and run ur mouth in 10 mths. I garantee ur foot will take place of your mouth then.
#40
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Originally Posted by sycotic_reject
...i've never heard of a choppy turbo'd motor, all of them always are idlieing very smooth, they usually have about 115 lsa's in them
http://www.brianhouk.com/EVO/media/m...AMSEVODYNO.wmv