rocker ratio.........
Thread Starter
Safety Car
Joined: Jan 2009
Posts: 3,873
Likes: 25
rocker ratio.........
My 81 in california has that 260 hp goodwrench replacement, so the previous owner says. I new if it had the original 190 it was making every bit of it. So It runs very well. But its all done at 4500 rpm. Very good torque . everything else is as it came from the factory. Looked at 1.6-1.7 rockers. It seems they open and close way quicker, as well as adding some duration.
so what do you think? It's cheep and easy. And Im dying to get oil all over everything.
ramair.
so what do you think? It's cheep and easy. And Im dying to get oil all over everything.
ramair.
Race Director
Joined: May 2006
Posts: 18,703
Likes: 2,572
They will increase lift only, the cam controls the duration and the ramp design on the cam controls the rate of opening and closing. If lucky you will gain 10HP but probably less. The engine has only 8.4 compression and very mild cam. Have you tried recurving your distributor?
Last edited by MelWff; Dec 22, 2011 at 02:15 PM.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Installing 1.6 rockers will likely cause interference with the pushrod holes on those stock heads. There's a bit of power to be gained (10 HP or so) but it's not a great investment.
Regarding duration, changing rocker ratio doesn't change the actual duration...but it does increase the effective duration as the valves will also reach maximum lift faster, meaning that the valve will be open further, longer any time after initial lift so the "area under the curve" is greater.
Regarding duration, changing rocker ratio doesn't change the actual duration...but it does increase the effective duration as the valves will also reach maximum lift faster, meaning that the valve will be open further, longer any time after initial lift so the "area under the curve" is greater.
Le Mans Master
Joined: Oct 2006
Posts: 8,940
Likes: 35
From: El Cajon California
Installing 1.6 rockers will likely cause interference with the pushrod holes on those stock heads. There's a bit of power to be gained (10 HP or so) but it's not a great investment.
Regarding duration, changing rocker ratio doesn't change the actual duration...but it does increase the effective duration as the valves will also reach maximum lift faster, meaning that the valve will be open further, longer any time after initial lift so the "area under the curve" is greater.
Regarding duration, changing rocker ratio doesn't change the actual duration...but it does increase the effective duration as the valves will also reach maximum lift faster, meaning that the valve will be open further, longer any time after initial lift so the "area under the curve" is greater.
Corvette Camshaft, 260 High Energy, Competition Cams, Small Block, 1955-1980
http://www.ecklerscorvette.com/corve...1955-1980.html
