I was dead set on the cc503 as of yesterday. Even bought Alex's springs and some 1.6RR. About to purchase the cam and did a little more research. My LT1 is in a lighter car and I really want it to rev higher. Eventually I will build a nice bottom end. My question is can I get away with a more aggressive cam with the springs and stockish heads. I'll be doing a DIY port and polish job. Nothing major just cleaning up the edges really. I understand the risk of the stock bottom end with a cam that is capable of high rpm's. I'm just worried that I wont be happy with the cc503. Would I be better off with the GM847 or maybe the cc306? Any suggestions? Should I just stick with the cc503 while on the stock bottom end? Thanks

 

I would go with a custom grind since your looking for something pretty particular, you can come pretty close to the behavior of the 306 without losing so much drivability. I would also wait to do the cam until I could afford the head work

If a shelf grind is a must I would probably stick with the 503 for now or look into the xfi 467 which would be a good middle ground between the 306 & 503 but would probably require proper head work to be utilized to its full potential.

 

All I can say is to NOT underestimate the 503 it has brought many into some good #s....

 

I have a Lunati Voodoo 219/227 .545/.560 112LSA cam with shaved heads and I'm pretty happy with it this far. I am shifting at 6200 through my 4l60e.

 

I think I'm going to stick with the cc503 with a decent set of 1.6rr's. I don't want to push the bottom end too much. Also I want to know that when I'm beating on the car that I'm getting it's full potential instead of holding back due to lack of air flow though the heads, weak bottom end, etc.

 

confirm the Alex springs will accomadate the lift you get WITH 1:6 RR & 503

 

The springs are rated at 550 with 130lb seat pressure. I'm thinking it should do OK....

 

It's pushing it with those springs and lift with 1.6 rrs

 

Do not do an 847 with stock displacement. You will need to tune/gear and/or stall accordingly or it will be a miserable piece of **** to drive. That cam is far too big for stock cubes. You will end up with the same kind of performance results as if you were to go with a smaller cam with shittier gas mileage.

 

....you need to do the math on what the 503 cam is WITH 1:6 RR........it is .544. That is WAY to close to the max lift the Alex spring (.550)

You need a different spring, like this.

http://www.jegs.com/i/Crane-Cams/271/10308-1/10002/-1

or run 1:5 RR with the 503 cam and Alex springs

 

The 503 needs to be taken to 6600rpm as it is for best times, any bigger cam and you'll only need to go higher. Stock bottom end (rod bolts are the weak spot) is pushing its luck at 6600rpm, begging for mercy at 6800, and a time bomb of pure luck and praying you got the positive side of manufacturing defects at the PCM limit of 7000. Some motors who got the weak side of manufacturing defects blow their fun load at 6300. Stock cam on 1.6 rockers needs 6300 for best times, a 503 will be great with 0.026" head gaskets, 7/16 ARP studs, and NSA rockers, but id step up to a dual spring for pure insurance to shift at 6600. If the outer spring breaks, the inner spring will keep it in place for a little bit, rather than risking piston to valve contact immediately and destroying the bottom end. If you find some old threads on 503 times vs 306 times on stock heads and bottom end you'll see the 503 is right there with the 306, but the concensus is it drives 100x better.

I wouldn't mess with the intake to head area, by widening that out you are actually hurting airflow. That's an old school "I got a 3/4 race cam" bullshit that's been proven wrong by serious builders and advances in CFD models. The air now has to accelerate through the skinny part of the intake, slow down where it widens at the head, then accelerate again through the port, any time you have a change in velocity you waste energy, like floating in a tube down a river, as it goes from deep to shallow or shallow to deep, there's a bump, because the water has to accelerate or decelerate, you don't want to disturb flow. You are better off playing with the area around the valve stem to remove that restriction from casting. There's some good write ups around, one from Lloyd that is particularly interesting.

 

There is always a better choice then off the shelf for getting a better bang for your buck. I called Lloyd for his rec. Was building a street 355 and wanted something that had lots of low and midrange that also passed emissions. I was going to go with the cc503 untill i talked to Lloyd. He spec'd me a very similar cam 223/230 .565" on 112lsa. Very happy i talked to Lloyd

My new car ive been working on is a 355 11.5cr with LE1 ported heads, cc306, full boltons, etc. Completely different animal. The cc306 is a dog around town untill its about 3000rpm. Pulls hard all the way till 6500ish. Cam has an awesome idle chop but i miss that off idle power around town and being able to break the tires loose at any given moment. Made 380rwhp/378tq with my old 355 motor. Havent dynod the new car yet but i would assume in the 400rwhp range.

Bottom line is alot of guys buy a cam for HP numbers. The answer is and to be completely honest id give up the 20rwhp and have a motor that has the fun factor for the street with USEABLE power.

Hope this sheds some insight having had both types of cams.

 

The motor is in a 90 supra with a T5. The rear gears are 373 (I think). The car is completely gutted and IMO doesn't need the low end power at all for the fun factor. The problem I have with the car is that it's fun to cruise around in (part throttle), but when in WOT over 3500rpm it feels slow. lol. I think it's a combination of rear gears and the trans but I think the car needs the higher revs.


So for now, I'm going to take a chance and go with the cc503. I have a spare motor in the garage that I want to build along with a set of heads while hopefully still driving the car. This is just a play toy and something to turn some heads. Not really chasing every HP. Thank you guys for your input.

 

Oh, right now the tune is set up for the fuel cut at around 5500rpm. I'm shifting at about 5300rpm.

 

OP, pay attention to those gents above and get better springs. There is a strong chance your are going to coil bind using the CC503/1.6RR with the Alex springs.

Not trying to be mean, but don't be stupid and ignore solid advice from those who have been there and done that.

Without a doubt, it's because of my good valve springs(using PAC 1518s with my CC503) as to why my motor is still together. I made the mistake of pulling my trans into 2nd from 3rd....trying to go to 4th. Saw the tach briefly peg at 7K as the rear end locked up and the thing jumped sideways with me.

 

I have run the Lunati Bare Bones 218/228 in about 3 different engines now. It is a revised version of the Hotcam with similar specs. I actually just finished tonight dialing in a 1998 4x4 Yukon with a 5.7 Vortec running the Lunati cam. It is very streetable even in that heavy lifted 4x4 on 37s. It has a 2,200 rpm converter in the 60E and 4.56 gears.

 

Taking yall's advice on the springs. Contacted Alex about returning them. What are some good springs that will work great with the cc503 but I could also grow with? Maybe eventually run the cc306 if I wanted to down the road.

 

Oh, Forgot to mention these are iron heads.