Opinion needed on a 496 cam
#22
Registered
Thread Starter
I know how hard it was to trip the 70 mark with a 242 LS. Took a lot of fine tuning of an aluminum headed 502 (about 525+ HP) and a shortie to get there for us. Best GPS speed was 73.4 in the end. Actually Bob was very helpful in tuning the motor to get there, even without me ever spending a dime with him at the time.
Anyways, on to the new project
Motors started out as 1995 Gen V 502 mag motors (EFI)
Bored to 509 - 9.2-1 JE pistons
H beam Rods
Stock heads
Crane Roller rockers
HP 500 intake
HP 500 Carb
Thunderbolt IV Ignition
Gil Exhaust without silent choice
Now the cam was setup for the origional EFI setup that I removed, sorry I like the carb better for me. I can work on it, and my goal was to remove this flat tappet cam and go to a good roller from Bob.
Billet Racing Cam
550/558 lift
231/239 Duration
114 Seperation
I have no idea where I am HP wise and I am pretty sure the cam and intake combo are not the best setup. But, that should change when $$$ works out.
Anyways, on to the new project
Motors started out as 1995 Gen V 502 mag motors (EFI)
Bored to 509 - 9.2-1 JE pistons
H beam Rods
Stock heads
Crane Roller rockers
HP 500 intake
HP 500 Carb
Thunderbolt IV Ignition
Gil Exhaust without silent choice
Now the cam was setup for the origional EFI setup that I removed, sorry I like the carb better for me. I can work on it, and my goal was to remove this flat tappet cam and go to a good roller from Bob.
Billet Racing Cam
550/558 lift
231/239 Duration
114 Seperation
I have no idea where I am HP wise and I am pretty sure the cam and intake combo are not the best setup. But, that should change when $$$ works out.
#25
Registered
Thread Starter
jeffswav is correct, the listing is for the existing flat tappet cam.
I plan to upgrade springs, hydrolic roller lifters, and cam from Bob eventually.
I plan to upgrade springs, hydrolic roller lifters, and cam from Bob eventually.
#26
Registered
Join Date: Feb 2009
Posts: 319
Likes: 0
Received 0 Likes
on
0 Posts
I pulled some old dyno sheets, found a 509 basically started as carb 502 MAG, GM rectangle heads, GM dual plane I cut the divider down 3/4", Holley HP 950, stock ignition, the cam was Ultradyne flat tappet with your same duration specs but .570 lift both sides. Engine made 508Hp @ 5200 rpm and 538 ftlbs @ 4300 rpm. A good roller cam with same other parts except simple port work to the exhaust side runner floor and short turn, makes 565HP @ 5400 and 575 ftlbs @ 4400 rpm. Fuel distribution is better with a single plane manifold, it is easier to maintain consistent EGT with a single plane. Hope this helps.
#28
Registered
Thread Starter
Ok, so he didn't listen to Bob (RMbuilder) or me and went with the cam I mentioned in the 496. Honestly what should this thing run like? I think his boat is very forgiving on combinations as far as getting on plane.