got an 06 rcsb with a 99 lq4 its got longtubes, no cats, ported throttle body, ported and polished 317s milled .025,cold air intake, currently has a 3500 stall but its coming back out to get cut and cleaned, and its got 3.73s

currently has a comp 223/223 .637/.637 on 112 (specd by texas speed) yea its got a lot of lift but didnt put down the number we were hoping for


my question is what cam do u think would be best in the truck. It is a DD too so nothing too outrageous

 

something like a 226/230 .59x/.60x. LSA @112, ICL at 109, using comp lobe profiles. That would be a pretty mean cam

 

which comp profiles?

 

xer intake 226 dur at .585 lift with 1.7 rockers
xfi exhaust 230 dur at .605 with 1.7s

This is just an idea, don't know if they would work well together or not. Best to pay some a couple of bucks to spec you a cam.

 

well almost everyone ive talked to says 228 or higher on the duration and 6xx lift which is pretty close to what u just told me. found a couple of cams for cheap but prolly gonna end up gettin one speced out so i dont have to go through all this again.

id hate to see 310hp on the dyno again

 

Well, you are .025, so I would be careful with the lift on the cam. if the piston touches the valve, its not good, you know that. The best thing to do is try to get the flow numbers for your heads, that way you can have a cam speced that will be spend the most time in the lift area that the heads flow the best. If the heads stall (CFM decreases) there is no point in going to that point. Like my heads, the CFM drops off at around .585 lift, so my cam peaks at .578. Having the flow #s is key to getting a great matching cam.

Thats not to say that a shelf grind wont work, its just that you wont be getting everything you can.

As for the duration, in a DD, like mine, I would stay at or below 228. As you go up in duration, you are raising the powerband for the most part. 228 and above, with a 112 LSA and 109 ICL would be a good combo for a powerband that peaks around 62 - 6800 rpms. I don't like to spin my stock bottom end past 6200, so I got a reverse split cam 218/214 @.578 lift. Good for making tq low in the rpms and doesn't peak too high. I loose that high HP # that everyone likes, but I get more useable power under the curve, where most of my time is spent anyway. I am not preaching the reverse split, thats a fairly hot argument.

If I were to change cams, without changing anything else, seeing as how I will be putting in 3K converter soon, I would probably go with something in the arena of 222/226 .58x" lift, LSA 113 ICL 109.

 

not sure on exact specs on heads just remember at .630 lift they flow 325 and they never drop off just keep climbing

 

something with the combo is WRONG. i put 276 hp to the tires (35's) in a 4x4 stock heads and cam...

 

You need to pull the intake duration back or the compression up. Mill some 243's with the same cam at about 10.5-11:1. Add the tall FAST intake and the larger TB or the TBSS intake ported with a 90mm TB. You should be significantly better. Also, install it straight up on the 112 to get your peak power a little higher.

My 220-224 .575" on 112+4 was almost too "big" for the 9.5:1 LQ4.
My 220-230 .581 on 116+3 is really flat before the forced induction.

 

yea something is wrong...thinking the spring might have something to do with it....they are pretty old...if that doesnt fix it gonna go with a different cam. prolly a 228/230 .600 .609 on a 112.....too big? no such thing lol