ignition/valve float?

[snzuloz]

comp cams 212 212 flat tappet with champion gn1 heads with their supplied springs. 1.65 roller rockers both intake and exhaust. anybody know what rpm range you can run these out too? don't know if i'm getting ignition problems or floating the valves a little. big stuff 3 shows all is well with the air fuel ,timing etc. only starts too occur at about 4950+ rpm, figured with these heads and milder cam should be good for at least 5500-5800 rpm. anybody out their running big stuff 3 , would like to get some feedback of some ideas of how too set up car, overall timing for both pump and c-16, boost levels etc. currently running stock .030 over with steel caps,champion heads, 212 212 flat tappet cam, pt-70 turbo, 70mm throttle body, eastern front mount, 4 inch intake, 3 inch downpipe, 55lb injectors (will be upgraded right away), big stuff 3 . any help would be appreciated.

 

[Alaskabuick]

float?

I have been battling this same issue forever. Have a 212/212 roller. Still have not figured it out? My problem occurs at 5300, I get a valve terrain noise and the car stops pulling. Boost or no boost it happens with rpm.

Am going to try a different lifter to see if it helps?

I am running behive springs, I used to have the standard spring that came with the chapion heads. I did the same thing then but at about 5000 rpm.

Pulling my hair out to resolve this.

good luck, I will post my results if the lifters help.

Dennis