Biggest cam without valve piston contact?
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From: Chicago Land
Biggest cam without valve piston contact? I will be running 5.3 heads and milling them slightly to run 11.3 compression. What is the largest cam i can run with this set up. Also what do you feel is the best cam for this set up. Choppy idle no problem. Let me know. TIA
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From: Chicago Land
Re: Biggest cam without valve piston contact? Can i get some thoughts on this. Not saying i will use the biggest cam but just want to konw how much lift and all you can have. I am not sure if its true but i heard of a guy running over .600 lift on stock heads.
Re: Biggest cam without valve piston contact? What you should do is work with someone like Speed Inc. a place that has installed like over 100 sets of LS1 heads and cam. FYI they are open til 8pm on Wednesdays if you wanted to drive down and talk to Tom, Larry or Jim in person.
I am not sure that 580+ lift stuff will fit without flycutting the stock pistons.
I would not go over 228 duration for stock bottom end car I have not seen stuff much bigger make more power.
<small>[ November 12, 2002, 03:26 PM: Message edited by: Pro Stock John ]</small>
I am not sure that 580+ lift stuff will fit without flycutting the stock pistons.
I would not go over 228 duration for stock bottom end car I have not seen stuff much bigger make more power.
<small>[ November 12, 2002, 03:26 PM: Message edited by: Pro Stock John ]</small>
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From: Chicago Land
Re: Biggest cam without valve piston contact? I might talk to them about it. I just need to install it myself because im poor. I was just wondering how big i can go so i can figure out where to go from there. The .600 cam was probably just street racer talk.
Re: Biggest cam without valve piston contact? I am running a 0.591" lift cam with 0.040" milled 5.3L and flat top pistons. As Mike from MMS told me, that leaves about a hair of clearance. Hey, he recommended the cam and I have had no problems so far <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
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From: Chicago Land
Re: Biggest cam without valve piston contact? 0.040 is on 5.3 heads. That has to be like 12 to 1 compression. I am only planning on 0.015 milling to run somewhere in the neighborhood of 11.3 compression. I am thinking of running the .595 lunati cam with 112 LSA. Anyone have experience with this.
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From: Louisiana
Re: Biggest cam without valve piston contact? I recommend reading this article about camshafts to better understand.
http://www.elgincams.com/campaper.html
Justin
http://www.elgincams.com/campaper.html
Justin
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From: Chicago Land
Re: Biggest cam without valve piston contact? I konw the cam is pretty big for a 346 but i am also building a 382 so i need to keep the cam for that too, thats why i am going a bit big with this one, so it makes decent power when i get the stroker.
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From: Baton Rouge, LA
Re: Biggest cam without valve piston contact? Max valve lift has VERY little effect on piston to valve clearance. At peak valve lift, the piston is furthest away from the valve (on its way down and away from the valve). It is only after the valve has completely opened and is on its way up when the problems begin to start as the piston is pretty much chasing the valve up at this point.
Piston to valve clearance becomes a concern during the overlap period. This occurs near the end of the exhaust stroke and at the beginning of the intake stroke, when both valves are open for a small period of time.
Duration, intake centerline, ramp rates, etc. all play much more important roles in determining if a cam will clear or not.
Piston to valve clearance becomes a concern during the overlap period. This occurs near the end of the exhaust stroke and at the beginning of the intake stroke, when both valves are open for a small period of time.
Duration, intake centerline, ramp rates, etc. all play much more important roles in determining if a cam will clear or not.
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From: Chicago Land
Re: Biggest cam without valve piston contact? Here are the exact specs. HYDRAULIC ROLLER, Rough idle. Excellent for large cubic inch high compression race engine. 3500-6500 300°
300° 242°
242° .595"
.595" .350"
.350" 112° Sep
108° Int C/L 13°BTC 49°ABC /
57°BBC 05°ATC 55009LUN
I want a lunati cam and really dont want to go custom grind right now.
300° 242°
242° .595"
.595" .350"
.350" 112° Sep
108° Int C/L 13°BTC 49°ABC /
57°BBC 05°ATC 55009LUN
I want a lunati cam and really dont want to go custom grind right now.
Launching!
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From: Houston
Re: Biggest cam without valve piston contact? The advertise duration dose not say much...
Jason is very right!!!
about 10degrees BTDC you check the ex and 10degree ATDC you check the In. that's way your P/V will be closest.
The lift have very little too do with it.
big duration cams is where your problem is.
.600 lift on a 220/220 cam is nothing. be some nice ramps <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> so fine out what the largest duration people are running, and check your P/V before running your car.
Brent
Speedaholics
Engines & Cylinder heads
Jason is very right!!!
about 10degrees BTDC you check the ex and 10degree ATDC you check the In. that's way your P/V will be closest.
The lift have very little too do with it.
big duration cams is where your problem is.
.600 lift on a 220/220 cam is nothing. be some nice ramps <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> so fine out what the largest duration people are running, and check your P/V before running your car.
Brent
Speedaholics
Engines & Cylinder heads
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From: Chicago Land
Re: Biggest cam without valve piston contact? Yeah but its the same reason i bought a chevy, hooker headers, weld wheels, mickey thompson tires, its that whole brand loyalty. Lunati makes great cams for SBC and BBC engines. Sounds stupid but i have seen a local car have great results with a lunati cam that has over .600 lift with a custom grind. From experiences of people around my area with all types of cars lunati has the best results. This includes my dads race cars back in the day. Hard to beat a 427 1969 camaro going 8s with a bunch of highschool kids from the 70s owning and working on it.
