So I have a ZZ4 cam that I am goig to install and I came upon a tempting deal on a 503 cam. Is the 503 much better, and if so would it be worth the extra $$$?

Stats:
ZZ4;
IN - .474, 209 @ .05
EX - .510, 221 @ .05

503; (w/ 1.6 RR)
IN - .537, 224 @ .05
EX - .544, 230 @ .05

 

i chose that cam because it kept the rev's in the acceptable range, had a nice lope, and people have run some really good times with it.

you would see a huge improvement.

 

The ZZ4 installed at 4deg retarded should peak at 5600. On desktop dyno (i know just for a geustamit) The ZZ4 cam makes a hair more power every where compared to the 503, I am wondering if thats true.

 

desktop dyno eh? there is a reason why most people do not use those. and there is a reason why the ZZ4 is NOT a popular cam among LT1 enthusiasts. If I remember correctly it is meant to be a 350hp at the flywheel cam for a chevy crate motor. The 503 is a super popular cam, utilizing XE lobes from Comp, and the cam has shown to make on average 340rwhp+ with all the usual bolt ons and stock un ported heads.

bottom line: get that cam out of there! you can just tell by the duration and lift, that the 503 is bigger and will make more power without getting technical looking at the valve events.

 

Werd

And you won't have to rev into the stratosphere to get good power. Mine really wakes up at ~3000rpm and is screaming at 4000rpm. The 503 will like a set of higher numeric rear gears though, 4.10's in your case.

 

great cam loved mine, for everyday use. (selling soon by the way)

 

Don't know about Desktop Dyno but Engine Analyzer Pro has been proven to be within 2/3% of actual dyno pulls.
I use it and love it but it isn't the end all.It puts ya deep in the ballpark though.

 

Ok, so ya'll have convinced me to spend more money. Now does anyone know what rpm the 503 will peak at with stock unported heads?

 

5800-6000 somewhere around there, I think people shift it at 6200rpm or so.

 

Mine peaks at 6000 rpm

 

it peaks out at 5900 exact it will make a little more after that but nothing that will make a difference.