Think Ive decided on a cc503 cam for my stock lt1. It is a close ratio 4 speed t10, holley mechanical secondary, headers, and elec. water pump, so not entirely stock, but stock bottom end and all that. The car is not a daily but i do know i like bottom end a lot and not so much into winding it out everywhere so i think the 503 is a good cam but open to suggestions as well.

So my question is, what else do i really need. Are springs, rockers, timing set really necessary?

 

For a factory roller SBC, you might consider the equivalent cam 08-423-8. Same duration and lift but 110*LSA. Of course you could use the cc503 aka 07-503-8 but you’d need to shave the dowel since it was made to fit a rather different cam gear.

be aware that both of these are step nosed cams only meant for factory hydraulic roller blocks. There are retrofit rollers with the exact same grinds but those start with 12-xxx-x.

 

And yes, springs are 100% required for anything with a lift past .460” on pretty much any factory SBC. PAC 1218 and 1518 are popular choices. That cam would want about 135# on the seat and somewhere around 305# at .537” .544” that cam would have on 1.6rr.

 

Ok a little confused here. The 07-503-8 (cc503) is a specific LT1/LT4 cam but you are saying it requires modification to work?

 

Sounded like you’d done a intake/ carb swap on a 2nd generation SBC from 92-97 (“LT1”), so if that’s what you have I’d have assumed you may also have ditched the 92-97 LT1 timing set. Or are you referring to a 1970 LT-1 mechanical flat or hydraulic tappet engine? 87 & up hydraulic roller engines use a step nosed cam, so does the 92-97 LT1. Difference between those is the timing set and hence the cam dowel length. 86 and prior SBC won’t have a cam retaining plate or the step in the cam nose for it.

 

Thanks for the response. I am running a 96 LT1 factory roller motor, carb intake swap. I intend to ditch the opti. I havent torn into the motor yet so i still have stock timing set although I have just about everything else on hand except cam and valvetrain stuff.

My goal is to run the CC502 Cam and Bullet VS2700 spring (which i believe can be used with stock retainers / locks / locators - after doing research may be my best choice, also price point, please correct me if Im wrong) I want to know if I can run the stock timing set as well? Don't want to spend a ton "over building" the motor unless it is highly suggested (more into cruising/touring and not redlining everywhere) ALSO Can I run 1.6 pre 86 roller rockers on the LT1 (3/8 stud - Stamped steel with roller tip) I had these on an 87 factory roller factory carb 305 and liked them and the entire setup as a whole, very dependable. I think they'll work but want to get a confirmation if i could.

 

Ok thanks is for clarifying. This is the timing set you have now.

Timing set

Notes at the bottom explain a bit about the clearance distance, etc. The little extra gear rides on the teeth on the back side of the cam gear and turns a shaft that has a splined end that couples to the water pump with a metal sleeve. This is where the longer (than roller SBC) cam dowel comes into play. Should give you some things to consider, though you could easily retain this gear and water pump setup.

as far as valve train, self-guided rockers could work but wouldn’t be advised. Without any head modification (slightly deeper seat) for guide plates and enough rocker stud to run the 3/8-24 and 1.6rr you’d be struggling to get it how you want it. Though it could be done without any machine work on the head castings. The rocker stud and guide plates arrangement that way would likely need a change to pushrod length which doesn’t have to be a big deal, just measure and order. LT1 cams all have an oil pump drive gear (melonized) that would drive a traditional distributor just fine, with the appropriate distributor drive gear.

One other thing, with 3/8” rockers stud girdles wouldn’t be a bad idea but switching to 7/16” studs is cheap. Both have 7/16” - 14 threads on the bottom anyway.

 

Good info here. The part about the water pump gear --- I am going to be running an electric water pump and for cleanliness would like to remove the factory water pump drive gear and plug the hole in the timing cover (Was going to use a freeze plug or pipe plug or something, havent decided yet)


How will this affect the cam/timing set?


I found a nice spring kit on Alex's parts that I think I will go with (the ones previously mentioned I found people have had issues with) And I want to use a set of 1.6 stamped steel rockers with the roller tip from Summit (Price point) I think this setup will work.

 

Is this for a vented/pinned drive optispark, or non-vented splined drive opti? I believe the splined shaft for the opti is on the cam gear?

 

I can only say that I *think it is vented, because it's a 96. I haven't done any teardown yet. Didnt want the thing open to the elements for too long.

 

Perfect. If that's the case then you can save a whole lot of money by not having to get a LT1 specific timing set.
https://www.summitracing.com/parts/clo-9-3157

That is a high quality piece. You can spend much less if you want. Any SBC chain will work if you aren't going to use the W/P. Just make sure it's a true roller. Stay away from double rollers. Not necessary for your application.
You will still need to use the crank sensor reluctor since it too acts like a shim for the shortened crank hub.

Good info here:
http://shbox.com/ci/cam_install.html

 

Ok guys thanks for the good info. Can hopefully start tearing into it soon, might have to wait till school's out. Dont like leaving things disassembled for long periods of time.

 

Right. Coupler with splined ends. One is in the center of the cam gear and the other in the Opti (center) for 93-94 and why most aftermarket sets are ridiculously priced over $500. Timing cover has a tiny hole with a seal through it for this splined distributor coupler. 96 and up, many more options unless you do a pin drive conversion with a 95 cover (without CKP sensor) or the 96-97 cover with CKP and pin-drive Opti on a 93-94.

 

Thanks for the info. Gonna pull the trigger on that Cloyes set and also the cam. Had this weekend off so I pulled the heads today to find nice cross hatching on my cyl walls so I feel good about the motor.

I bought a PRW harmonic balancer for LT1 which has timing marks, comes with a new hub, key, and also a spacer. Do you know if the spacer is needed for my 96? Was gonna call PRW on Monday and see if they know.

 

The spacer is for pre-96 cars that don’t have the CKP reluctor. If you’re ditching the reluctor, use it.

 

Ok so since I no longer need the reluctor (going to use SBC style distributor) then I do need to use the supplied spacer?

Also I actually pulled the trigger on the 08-423-8 cam you suggested rather than the cc503 cam. I didnt want to shave the dowel pin and also think Ill prefer the 110 lsa.

 

Yeah, use the spacer. Otherwise your pulley alignment at the crank will be too deep without it. I think you’ll like that cam. It’ll sound like the intro from Hot for Teacher at 750RPM lol. And it’ll pull super hard from 2800-5800.

 

Lol awesome. Building a cruiser so the low end torque is what Im after. And i do love a choppy idle. Thanx for the help.

Now for the oil pump drive... do i just pull that completely out and simply replace with distributor shaft?

 

Yes. Becomes just like a traditional SBC oil pump/ shaft/ distributor drive gear arrangement. About the distributor gear- be sure to use a compatible gear. If you call
Comp they’ll try to talk you into buying their high dollar composite gear. Don’t use a bronze gear. The gray iron gear most aftermarket dizzys come with won’t cut it (most of those were meant for hydraulic flat tappet) and your bearings will eat the remains of it… a melonized gear is what you want. It’ll work with any material as well as the composite gear. A good read on drive gear compatibility here. I’m 99% certain Comp’s rollers are SADI..

 

So I'll be using an Accel HEI "performance replacement" distributor (new in box for $25) Summit lists the gear as melonized, Holley's site just says "iron or steel"

Will this be ok? Pretty sure I used this same distributor on my roller 305 w/o issue so initially thought I'd be OK but that was several years ago