hyd. roller cam rpm's

[blown69nova]

My engine will not go past 5900-6000 rpm and power falls off @ about 5400. I seemed to be running out of fuel because of seeing lean afr's, but now am thinking maybe it's in the valvetrain.
#6 intake rocker slid off on the dyno last year.
383 sbc
TFS 195c heads
springs have 120lb seat, and like 375 open
comp cam xe hyd roller
224/236 @.050 dur., .560/.570 lift w/1.52 comp magnum rockers
116 lsa
Any thoughts on this? How cab you tell if your floating valves, and has anyone tried the AFR "rev kit"?
Thanks, Steve

[CarlC]

Mine is similar except for 406ci and 230/236 on the cam. It max HP's at 5200 RPM. It's not surprising that yours max'es at 5400 RPM.

Mine will float the valve at 6000, but the valvetrain is very light. Most hydraulic roller cams, expecially the aftermarket varieties, can't handle much more than 6000 RPM

[Turbo Hen]

Steve you're probably out of cam @ 6000RPM....you may need some more durations.

See what spring pressure your cam requires & test your springs to make sure they are still up to snuff, especially if the heads were bought assembled.

The AFR Hydrarev kit i presonally think is a waste of $$$ for your application, your cam isnt agressive enough to use it. Check the spring pressures on the heads fist.

-Carm

[blown69nova]

Thanks for the replies.

[Lowend]

With a Hyd Roller I'm not suprised if the motor is done at 6000RPM... that is about where all hyd rollers start to loose it. Just too heavy

[MonzaRacer]

Comps beehive springs and light weight retainers will get you some more rpms but this engine should pull hard through 6k easy. IF it lazt up to 6K then you may have either not valve float but its just kind of "getting" lazy and with a HYD roller you shouldnt need 125 lbs of seat I have a LT4 Hot cam and it pulls to 6500 and I am using onle "Z-28" springs and new seat preasure was 100 psi.
As for Rpm ing Hyd roller yes you can but why its not for high RPMS I would kee pthe ceiling at 7k and never push past 6500 with those heads look for low end torque not screamer rpms.
THAT design engine doesnt need to pull high R's tune it to pull hard to 6k and save the rpms for short stroke engines.
As for HYD roller being too heavy i dont agree its just a matter of harmonics based on the vavletrains control device IE springs. If they can make the calloway and lingenfelter tweaked Corvettes pull to 7k+ then you just dont have right parts.
My next SBC will be a 283 with a HOT cam and Comp Beehive springs and I figure it runnng in the 400 hp range and still have a lower torque rpm range than you would expect from a 283.
Good Luck
Lee Abel

[Lowend]

Its not the retainers that are the problem... its the lifters, they weigh a ton

[EFI69Cam]

Its not the retainers that are the problem... its the lifters, they weigh a ton


Its not the weight of the lifters, but the inability of the plunger to hold against the acceleration of the valve train.

[Lowend]

that don't help either