New Cam For The LT4
Drifting
Joined: Oct 2001
Posts: 1,648
Likes: 1
From: Denham Springs Louisiana
My signature will give you a good idea of what the HotCam and roller rockers did for my LT1 (302 RWHP). Should be even better for the LT4. BTW...it still passed all emission inspections and was very drivable on the street.
Melting Slicks
Joined: Mar 2004
Posts: 2,141
Likes: 2
From: Pittsburgh Pa
you will be beyond the springs capabilities with a 503 and 1.5's i promise you that. i am using crane 10308 springs and i have a comp xfi 280 in my lt4 with 4.10 gears and its fun but i think a custom cam would have been a better choice if i didn't have that cam laying around.
Melting Slicks
Joined: May 2007
Posts: 2,382
Likes: 2
From: Kathleen FL
I know the CC503 cam can handle stock LT4 springs with a 1.5 rocker ratio. I had a setup with it before without problems. Comp Cams does recommend the use of their 918 springs over stockers. According to GM's website, the stock LT4 springs are good to a .525 lift. The CC503 cam's lift specs with 1.5 oem rockers is .503/.510. Close, but still well within specs of the stock LT4 springs, AS LONG you have a 1.5 rockers.
The LT4, of course, has the stock LT4 springs with 1.6 roller rockers. Knowing the specs of the LT4 Hotcam already, you would actually be maxing out the lift on those springs. The LT4 Hotcam's lift specs are .493/.493 with a 1.5 rocker ratio. Using the LT4 Hotcam on a 1.6 rocker ratio would be .525/.525. Now that looks pretty darn maxed out to me. Now if you were to run a CC503 cam on a stock LT4 with its stock LT4 valve springs with the stock 1.6 rockers, that is potential trouble there.
The LT4, of course, has the stock LT4 springs with 1.6 roller rockers. Knowing the specs of the LT4 Hotcam already, you would actually be maxing out the lift on those springs. The LT4 Hotcam's lift specs are .493/.493 with a 1.5 rocker ratio. Using the LT4 Hotcam on a 1.6 rocker ratio would be .525/.525. Now that looks pretty darn maxed out to me. Now if you were to run a CC503 cam on a stock LT4 with its stock LT4 valve springs with the stock 1.6 rockers, that is potential trouble there.
