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turbo cam ??'s

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Old 06-12-2005, 05:06 PM
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so how is high lift for turbo then? i understand the over lap cause you don't want to blow your intake charge right back out the exhaust and scavenging the exhaust doesn't really play in this either with the turbo because of the air being forced in and the back pressure from the turbo would probably not help scaveging at all. is this sound right or am i totatly wrong? if so please explain. i'm trying to suck up all the knowledge i can on this i want to but things one time. and when your considering a cam for a 4.8 remember theres that chance of going bigger cubes in the future. more than likely no bigger than a 6.0l though
Old 06-12-2005, 05:55 PM
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You're pretty much right on. Turbos have the backpressure hting to worry about which is another reason valve timing events are so important for max efficiency. Lift is going to be in part deptermined by your head flow characteristics but I get lost right about here. LOL

It seems like although they use low Dur. most turbo cams are high lift athough I'm told it's not really a big concern like it is for N/A.
Old 06-12-2005, 06:33 PM
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well i have the ls1 heads on there now which shuld help flow i would think. i've been looking at that 99-227/224-114 like TurboBerserker was saying looks like a nice cam i guess. any other inputs??
Old 06-12-2005, 07:24 PM
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I actually think that 227 will be kinda big for a 4.8. It was the best on the page you offered, but as F8L said, turbos do well with "smallish" cams ( bear in mind that my cam is smallish in a 408 -- doesn't even lope -- If I was NA or N20 I'd have a 248/256 in there )

I'm not sure what will be good duration in a 4.8. If someone can help out there, we can figure out the turbo part.
Old 06-12-2005, 08:12 PM
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what is the stock duration??
Old 06-12-2005, 09:00 PM
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stock is 114LSA in the trucks and 117.5 and 119 is F-bodys. I have a whole list of stock cam specs if you want them.
Old 06-12-2005, 09:01 PM
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Originally Posted by TurboBerserker
I actually think that 227 will be kinda big for a 4.8. It was the best on the page you offered, but as F8L said, turbos do well with "smallish" cams ( bear in mind that my cam is smallish in a 408 -- doesn't even lope -- If I was NA or N20 I'd have a 248/256 in there )

I'm not sure what will be good duration in a 4.8. If someone can help out there, we can figure out the turbo part.
248/256 sounds like what i need. I may have to look into that one.
Old 06-12-2005, 09:02 PM
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I've heard that stock cams are fine with turbos.
Old 06-13-2005, 08:10 AM
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4.8 guys, how about a 220/216 .535/.525 112 lsa Should be ok for drivability, maybe a little thump. Will require tuning and a stall (2600-3000) though, I'd think, but should work with the springs.
Old 06-13-2005, 11:33 AM
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i've got ls6 springs with should be able to hold a little more lift than stock. i know there monsters compare to the one i took off the ls1 heads i put on.


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