Advantage to higher ratio rockers?
Advantage to higher ratio rockers? I was wondering if there are any great advantages for changing the stock 1.7 ratio rockers to something like the SLP 1.85 ratio? Im planning on changing my heads and cam on my 98 Z28 to a Patriot Performance package and possibly chaning the rockers. Would I have any limitations with changing the rockers as far as camshafts are concerned? Any forseable problems or upside I would see down the road as far as if I upgraded to a bigger displacement short block or adding nitrous?
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
Re: Advantage to higher ratio rockers? Higher Ratio = more lift. More lift = more air going in but also greater chance of valve hitting piston.
It'd probably be best to call Patriot Performance and see what they recommend... I know w/my TR224 higher than stock ratios aren't recommended due to the ramp speeds of the cam...
Figure if a cam is advertised as .560 lift that means that the actual cam lift is x=.560/1.7 = .329 so 1.85 ratio rockers would make youre lift 1.85*.329 = .608" lift... that's ALOT of lift... and would require good springs to handle it... (.560 was an example... dunno what lift cam you're going with)
so basically call patriot and see what they recommend... if they use fast ramps it's probably best to stick with stock ratio... also going higher ratio means you'll definetly want to clay to make sure you don't have to flycut the pistons
It'd probably be best to call Patriot Performance and see what they recommend... I know w/my TR224 higher than stock ratios aren't recommended due to the ramp speeds of the cam...
Figure if a cam is advertised as .560 lift that means that the actual cam lift is x=.560/1.7 = .329 so 1.85 ratio rockers would make youre lift 1.85*.329 = .608" lift... that's ALOT of lift... and would require good springs to handle it... (.560 was an example... dunno what lift cam you're going with)
so basically call patriot and see what they recommend... if they use fast ramps it's probably best to stick with stock ratio... also going higher ratio means you'll definetly want to clay to make sure you don't have to flycut the pistons
TECH Junkie
Joined: Mar 2002
Posts: 3,019
Likes: 0
From: memphis tn
Re: Advantage to higher ratio rockers? I run SLP rockers on my supercharged Tahoe they give a 10-12hp increase throughout the rev range by increasing the lift about 9 percent and greatly increasing the ramp speeds on the cam.They do require a valvespring upgrade.If you are changing heads the cost of a cam is about the same as a set of SLP rockerarms and think you would make more horsepower with a well selected cam than the rockerarms.
