I am getting ready to order cam and valve springs with 383CID with L98 113 heads I am looking at CC503 from help for this sight but the .51 lift numbers is scary to me I am imaging bent push rods and stuff like that what kind of spring is best LT4 or Beehive I would like to run rollor rockers 1.6 but that is even more stran on valve train do I need hardend push rods I would like to do this build correct the frist time I hate to redo stuff so what is the over all best way to do this how do I know that the valve spring can handle this before the nasty bent stuff

 

Hot Cam is about the only cxam you can run stock rockers and PR's with. It has VERY slow and lazy lobes that open/shut the valves slowly and will leave some power on the table compared to other after market cams even with the same idle, drivability and RPM range.

The Hot Cam is able to work with some $35 springs that have 105 lbs seat pressure and 275 lbs open pressure. Just about ANY OTHER aftermarket cam will need 130 seat/320 open and most shoot for 145 seat/350+ open for hyd rollers.

The ramp speed of these aftermarket cams and added spring pressure will REQUIRE good pushrods, good rockers, etc.

Lloyd

 

Use the spring the cam manufacturer recommends for YOUR specific cam.

Hardened push rods aren't specified for strength so much as they are for wear resistance when used with push rod guide plates.

RACE ON!!!

 

Well another newbe question are the valve springs the same as the LT1 or are they different amimal? When I look at the recomended springs on the 8-503-8 the spring look to big when I look at the recomended springs for the LT1 cam 7-503-8 they look like they will work better?

 

If you get a set of non self-aligning CC ProMagnum RRs (1.5:1 or 1.6:1) for 7/18" studs you will avoid any concerns over pushrod strength as you will also need hardened pushrods and guide plates along with a set of 7/16" studs. A set of 10deg forged retainers rounds out the list.

Lose the tin oil shedders from atop the (stock) springs and go with Ti retainers to further lighten the valve train and reduce strain.

If you go with say a ZZ-9 cam TPIS makes a compatable single spring w/ damper for a config. similar to the stock setup.

 

cfi and 65z01 hit most everything that needs to be said. use the proper spring. in your case the comp 987. however, since you are using a 113 head TPIS sells a manley spring that has comparible rates but isn't as fat. you could probably look the manley spring up in their catalog if you wanted to. it's a single spring but a very good one. same with beehives, those springs just rock ! also, spend the money on guide plates and hardened pushrods. the cheap comp cams pushrods are only $40 and 1pc trickflow chromoly rods are only $80 or so. also. if you have decked the block and heads a good deal you might need a 7.150 rod versus the 7.200 stock. have someone who knows their salt answer that question when they look at your motor and can see where the rocker hits the valve stem.

 

When the heads are setup there is a installed height for the springs. That info should come along with the spring recommend. This will prevent coil bind.

I always check the Valve Geometry when installing new cams. The pushrod length checker is cheap and easy to use. You can order pushrods in any length you need.

One other thing to look for if you go to 1.6 rockers. I have seen the pushrod rub against the bottom of the guide plate. Easily solved by filing some material off the guide plate. When you change from 1.5 to 1.6 you are changing the opening and closing of the valves. Why not just order a cam to do exactly what you want it to do and use 1.5 rockers.
My 2cents

 

I have been looking at the CC26981 beehive springs there specs are.525 Max Lift I am looking at a cam with .51 with 1.5 rockers the reason these look so inviding is my heads don't need machining for these springs

 

I just put a new comp cam in my Corvette with 113 heads and, I had to have the heads clearenced for the higher lift, I also used the valve springs that were recommended with the cam. Make sure you have the heads checked to see if they need to be clearenced for the extra lift and for a few bucks don't mess around with the stock valve springs, just my $0.02.

 

To CFI-EFI

I don't see anything wrong with what Lloyd said to warrant a BS. I don't see where he said anything about hardened pushrods. I think he is talking about the Hotcam in the same vain as other performance cams. I agree with what he said.

 

Heres my, .02c buy a complete package what ever it is.
you probably won't find one with push rods, guide plates and studs in a package, but who knows.
It seems like I spent a fortune piecing this stuff together.

 

If you are only looking at that lift use the GM LT4 /ZZ4 spring @$35

 

Having researched this issue myself for the past few months, the feedback I've gotten is that < .6" lift is peanuts. No way you're going to bend PRods (at least not from lift forces). Sure, some will say check everything and that's never bad advice either. Still....

I was also told that < .6" lift did not require checking piston-to-valve clearance with the stock pistons. At least not unless some mechanical changes in timing were going to occur.

Lloyd says the HotCam is about the only lazy cam that could use the inexpensive LT4 spring. But, even I think there are still a lot of (other) "lazy" cams left on the market. On that point, I'd say his answer seems "wrong". But, don't be putoff by this HOTCAM thing. Lloyd is probably considering that most people choose newer, more aggressive profiled cams these days. (That's what I think) Also, Lloyd has many happy customers! (Do a seach on Lloyd Elliot)

Certainly, it's safest to use the spring recommended by a cam manufacturer -- or at least go with what a head manufacturer says. For example many aftermarket heads come with springs strong enough for .6" lift or less. So, you shouldn't have to change springs for a .520" cam -- if loaded with ones for < .6" lift (as an example).

Is the OP porting (w 113's)? If so, the cylinder head shop doing the porting can recommend springs as well. If not porting, strongly consider it!!!! If you don't have a shop, contact Lloyd (or look for one in your area). Lloyd's pricing and results (flow #s) look very competetive to me. He can also recommend "package" setups.

As counter-point, I often got feedback indicating that "speed shops" always recommend their highest quality stuff. They might say you NEED a (dual) beehive spring -- when you might not. Same with hardened push rods and HQ lifters. If you're really worried, then buy what's recommended -- it won't hurt! Or, if you have the time/patience, go to independant machinists/builders and see what they think. They will help you figure it out.