I guess i'm getting old. I dont want a lot of lope, and really like the way the stock 350 TPI idles. But, in the name of power, i am going to cam it. Can you give me any pointers as to which of the following wont give a lopey idle?

http://www.summitracing.com/parts/cc...make/chevrolet

http://www.summitracing.com/parts/cc...make/chevrolet

Stock 083 ported heads, stock lifters and rockers, to a ported stock intake w/stock runners and 52mm TB. 3" exhaust. 3.27 gears, 2200 stall.

If theres another cam that will work (480 max) lemme know. Thx!

 

Probably the all-around best cam for a stock L98 seems to be the Comp "501"...

http://www.summitracing.com/parts/cca-08-501-8

Not sure what "480 max" is all about; most any decent roller cam will be above that. Maybe not by much, but still.

Replace the valve springs at the same time, no matter what cam you go with. Use whatever the cam mfr recommends, along with the hardware that goes with them. (retainers, keepers, etc.) Stock ones CANNOT control the valves adequately. Make sure you get their height set up right when you install them.

You will also find that stock stamped-rubber rockers flex so much, that at least 5%, and possibly as much as 10%, of the "theoretical" "on paper" lift, will be lost. The more cam, the worse the problem. Furthermore, it will be inconsistent from valve to valve. They are GARBAGE. I highly recommend getting rid of them and putting something made of metal in there instead, if for no other reason than to make all the valves work the same.

 

oh, that "480" came from 'stuff i heard' essentially stating that "480" is the max lift the stock heads can take w/o machining. did i hear that 'stuff' right? and in the interest of economy, can i go w/ aftermarket roller tips and still get the desired balanced result?

 

Is the "480" max lift for stock heads a rule IF you use the stock springs? Aftermarket springs give the ability to get a higher lift WITHOUT machining?

 

Castings vary. Some may be .460 some may be .490, hard to say but alot of stock style springs and retainers will contact the guide boss/seal somewhere in that range of lift.

You can get aftermarket retainers/spring setups that may give you more clearance. Beehive spring kit will likely give you well over .500". Another popular one is Alex's Parts spring kit with retainers that are ground down, say its good to .550". Guy on this forum has them on a vortec head running a .540 cam no issue

Another trick is using shims and offset locks to get clearance. Stack .050" under spring seat, use +.050" lock. This raises spring assembly up .050. Thus making that .470-.480" lift limit now become .520-.530.

So there are ways to go about doing this. Best to measure what your limit is on your heads.

If they were ported they should have had the guides cut down and screw in studs installed for higher lift higher pressure springs

 

The info I've received here is really appreciated, as I am still learning even moreso as a novice.

But I want to get back to my original quest: what aftermarket cam would you suggest I get that minimizes lopiness, perhaps an LT1 or LT4 cam since they were in production vehicles? Maybe one with a little more than those since a little lopiness is acceptable?

 

Either of the computer cams you picked or the 501 cam suggested will work good and minimize any lope. 501 will have a slight cam sound but very minor. Have you ever heard a zz4 crate motor in a old car at a car show or something? Has a slight cam sound, but exhaust system can influence that as can the tune

I wouldnt run the smaller comp controlled cam as its not much different than stock. It will make abit more power but i dont feel its worth it. Next step up you posted could work well.

You can also order them on a wider lsa if you want. Comp cams can do that at no extra. Tell them the grind number and lsa you want.

Most cams are on a 110-112. Most stock cams are 115-117. You could go comp 501 on a 114 and have good performance with negligible lope.

Lt1 cam isnt much more than an L98 with 1.6 rockers. Some more power but not worth effort imo

 

Orr, you are a true ambassador of this site. And I'm not kidding, your style is easily understood by a novice who wants to learn, without any demeaning commentary. I really thank you for the advice. I'm going with the 501, and asking for a special LSA of 114.

On another note, if using the stock valve covers, no head machining, Z28 spring setup (550 lift max type), can I use 1.6 or should I stay with 1.5 rockers?

 

You can get some 1.6 rockers to fit under stock covers, some may not. Comp magnums do fit but pro magnums may not. They are alot taller but i havent tried them under stock covers.
Other brands may be similar.

Unmachined heads, again its goin to come down to what retainer you use or if you do the offset lock with shims trick to gain lift clearance. I am not sure if z28 springs and matching retainers will give you clearance on stock heads to run .528" of that 501 cam. Retainer may need ground down. I would look into the Alex's parts kits or a beehive spring like Pac-1218's for sbc valvestems

 

will 1.52s work with the 501 but no machining?

 

Forgot to mention specifically but rocker type has more influence on cover clearance than just ratio. 1.5 or 1.6 on some of the big body full roller types may not clear. Need a self aligning narrow body type or use comp magnums which are roller tip only. Its a lower profile.

If you bought alex's parts springs you can run 1.52-1.6 rockers more than likely. You dont need larger ratio but it can help with some extra hp. You could even reuse stock rockers if you wanted but still need a spring package that gives you extra lift clearance from the valve guide