finishing the combo. . . .
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Teching In
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From: st.louis
finishing the combo. . . . so my build is getting started a little earlier than expected and i wanted to know what you guys would do? im geeting some stock lt1 heads from a friend for 60-75 bucks and i want to get them ported doesnt really have to be CNC'd also going to get the intake ported too while swaping the heads. what valve train is a more streetable arrangment and also what off the shelf cam would be a nice addition? oppinions and numbers work great thanks.
for an off the shelf cam I like Lunati, I have had good results with a baby cam on stock heads and I am sure it would be a solid performer on ported heads. My mods and dyno numbers are in sig
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Teching In
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From: st.louis
so in lift terms how would you describe a street,mild and race cam. and what kind of cc should i be looking for as far as the heads go for a 400hp goal?
lift really doesn't determine streetability IMO it is more the duration that raises your usable power so for a good street cam I would try to keep your duration at ~230 or less at .050 lift. I am keeping my lift numbers less than .575 lift mainly because of my springs and as I understand valvetrain stability on a hydraulic lifter goes to hell with anything above .600. My lift is at .565 and .545 respectively and I have had no problems with valve float or anything else all they way up to 6600 rpm. I am no expert nor do I claim to be so take it for what it is but those are the choices that I have made so far and it runs good. The only thing that I did that I wish I would have done different was my rockers. I cheaped out and got SA roller tip rockers because money was getting tight and I just wanted to put it back together but I have regretted it ever since. I would go with the COMP hi tech stainless rockers with 7/16 studs and guideplates if I were to do it again.
as for head cc it all depends on what pistons you are running and what your deck is at heads gasket thickness etc. Most ported stock castings are anywhere from 52 to 56cc when they are all said and done. Some people swear by dynamic compression ratios as opposed to static compression ratios and it seems that nothing higher than 9.5:1 dynamic for pump gas. Your cam choice affects your dynamic numbers but on the same note I was speaking with one of the sponsors on here that have gotten a lot of posts about their heads and mentioned dynamic compression ratios and he told me to stop reading forums and it is hocus pocus. I can neither confirm nor deny but I know that there are cars on this site that are running 12.5:1 static CR on pump gas with a huge cam so there must be some truth to it.
Thread Starter
Teching In
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From: st.louis
so what realy helps you make the power with a cam? is it the combibation of lift and duration? and if you were running on stock internals what would you go with, just trying to get a starting point this is my first V8 and its also a 6 speed with stock gearing although wanting to throw some 3.73's in the mix.
first of all duration doesnt determine "streetability," overlap does. you can run a 245 @.050 cam on a 118 lsa and it will probably perform better on the street than a 235 @.050 on a 105 lsa. i run 12.5 static cr on 91 octane with a rather large HR with a lot of overlap. i'm running about .620 lift with 1.6s and many lsx motors run .650+ with hydraulic roller on stock rockers even. head flow, intake runner length, valve size, headers, duration, lift and lsa all play into the rpm range of a motor.
