PARMY

eventually I will be building a 383, local guy will build the entire engine including ported heads etc I知 consider one of the 2 cams listed, they seem very similar on paper with the obvious differences, lsa and a few degrees etc. I知 just curious if anyone has used both and what the power differences are... which makes better power, more peak etc.

SS RRR

iTrader: (2)

With such small changes both will net about the same power. Why such mild cam choices for a stroker?

PARMY

BALLSS

the tune will be the primary factor of getting tailpipe emissions within spec. Discuss your cam choice with whoever does your tuning.

I have a smaller cam than the 503 in my 383 and have passed Calif. smog for years now

PARMY

SS RRR

iTrader: (2)

If it's between those two I'd get the one with more lift. You'll see probably right around high 300's for hp and low 400's for torque, IMO.

Purple Poncho

iTrader: (1)

I had a CC305 in a supercharged 383 with stock heads. It passed Ont. emissions back in 2001 or 2002. It is a small cam for that size engine NA no doubt but has great manners and passed the roller test at the time.

hokeplaya05

iTrader: (3)

FWIW I have a smaller cam in my 383 (214/224, 555/568, lsa 115) and I have to say, it must make at least 400tq to the wheels and probably around 380hp through a 6 speed. super fun to drive on the street, tons of low end torque and pulls hard up top for what it is. not the ideal cam for the setup but I am happy with it.....for now. wish it had more lope at idle though, can really only hear it on cold starts under 30* when the idle is really low in closed loop.

StealthFormula

iTrader: (35)

I was just about to rag on the cc305 a bit for being an old technology cam ground on some ancient lobes that came out before most of today's LT1 owners were even conceived but then recalled that it is now ground on Xtreme Energy lobes (same with the cc306). The Xtreme Energy lobes are still technically older tech but are much improved over the ancient Magnum lobes IMO. Honestly, both the cc305 and cc503 are decent cams. The cc305 on a 114 lsa was a very popular blower grind back in the day. I personally like the valve events of the cc503 more and think it's one of the best LT1 shelf grinds BUT there is more overlap in it (bad for sniffer test) versus the cc305. As said, tuning plays a big part in it however. Anyways, if it were me I would pass on both the cc305 and cc503 cams and call up Lloyd Elliott for a custom grind. The cam is arguably the brain of the motor and with a 383 setup like yours I would opt for custom (from a reputable LT1 individual) because there is value in having a cam with the right valve events to not only deliver optimal performance but to meet the goals, constraints, etc. of the end user more, just my .02.

bowtienut

iTrader: (1)

I'd choose the CC503 for a NA application.
The CC503 has less-ancient XE lobes and gives more area under the lift curve, better average horsepower, than the older Magnum lobes of the CC305.

Edit: just saw the post above mine. Never heard that there are now two different versions of CC305 cams out there .. ??

Gojira94

iTrader: (4)

Have a look at the valve events and LSA (overlap)

Comp 305
http://www.compcams.com/Company/CC/c...csid=1102&sb=2

Comp 503
http://www.compcams.com/Company/CC/c...csid=1111&sb=2

Comp XFI 467 (far better choice than either of the other 2)
http://www.compcams.com/Company/CC/c...csid=1107&sb=2

All are similar in valve events in terms of degrees. The 305 is old lobe technology. The 503 is a great cam for stock cubes where emissions may or may not matter, capable tuning helps. These 2 cams are very similar but the 305 has another degree of LSA to assist in staving off cylinder pressure bleed off during filling on the intake stroke. The intake valve closing event and ICL/LSA have primary effects on overlap, which will be your biggest enemy for emissions, as some of the air and fuel charge is leaving the exhaust port unburnt (= high NOX/HC). 3rd choice and others like it- the 467. Longer duration, higher lift, very similar valve events but very different lobes. And another degree of ICL/LSA vs. overlap. More power potential with no worse or slightly better emissions challenges for your tuner. Look at the lift it makes in the almost same number of degrees as either of the other 2. Cylinders will fill a lot quicker and more efficiently and atomize the fuel charge in the intake port a lot better.

Nobody asked what heads you're running on your 383. Care to share? If it's stock LT1 170cc heads then stop me, lol. The other 2 would be about your maximum choices for stock untouched heads.

StealthFormula

iTrader: (35)

To build off the above...I know many of us know this already but just as an FYI for any readers that may not...Comp Cams for whatever reason quotes the lift of the XFI lobed cams assuming a 1.6 ratio rocker and quotes the Magnum and Xtreme Energy lobed cams assuming a 1.5 ratio roller rocker. To directly compare the lift between cams a little math is necessary, here's the results:

cc305 lift w/ 1.6RRs = .544/.544
cc503 lift w/ 1.6RRs = .537/.544
XFI 467 w/ 1.6RRs = .576/.570

I dig the XFI 467 cam mentioned, nice specs on it and it's on more modern, more aggressive XFI lobes. I personally favor the XFI stuff and have been running a custom XFI lobed cam for the past 10-11 years now.

StealthFormula

iTrader: (35)

I had no idea myself until about a year ago when I was browsing Comp's website. I double checked today to be sure. They no longer list any Magnum lobed cams for the LT1s. The cc304, cc305 and cc306 cams are now available under the Xtreme energy lobe family. It's about time lol. Also, the 112 lsa version of the cc305 is no longer available, just the 114 lsa version is.

BALLSS

The XFI grinds in terms of published lift spec is with 1:6 RR vs the 1:5 on other cams.....if you are comparing "lift" #'s

FWIW I run the XFI in my 383. You need a good spring for the ramps of this grind. Lunati is what Lloyd advised for me

BALLSS

FWIW the XFI grinds published "lift" specs are with 1:6 RR vs the 1:5 of the other two cams mentioned so do the math for the other cams to get comparable lift #'s as Stealth did

I have the XFI in my 383. You need a good spring for the ramps of the XFI. Lloyd advised, and sold me, Lunati springs

EDIT: apologies for double post...hotel internet is slowwwww

PARMY

PARMY

Jazz-LT1

iTrader: (2)

I'm running the cc305 with ported stock heads, 2.00/1.56 valves and 1.6 rockers. Big flat torque curve and nearly stock sounding and very smooth. The engine was built about 8 years ago though and I'd likely do things differently today. Long story short, talk to the tuner and do the research. Asking here doesn't hurt but everyone is going to have different opinions. Valve size, porting and other factors apply here as well.

PARMY

hokeplaya05

iTrader: (3)

that is pretty much my exact setup besides the cam difference and I would agree, around 380hp and over 400tq. wicked fun on the street, don't need to rev it out like you said, tons of torque down low. good luck with the build